Due to scarcity of fossil fuels and their severe environmental consequences, the development of high efficiency energy conversion devices such as fuel cells (FCs) have gained considerable attention. The specific energy conversion efficiency of FC is highly influenced by the activity of the electrocatalysts. The Pt is widely used as an electrocatalyst due to its high activity and stability, but its high cost and depletion of resources hinder its commercialization. One of the workable strategies for the practical application of Pt is to reduce its content by alloying with some non-precious metals and simultaneously maintain its electrochemical performance. In this context, we developed a low Pt-loaded Pt-Ag/C alloy electrocatalyst via a gradual reduction process. The electrochemical performance of the as-synthesized catalyst was investigated by cyclic voltammetry (CV), linear sweep voltammetry (LSV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS) using the three-electrode electrochemical workstation at room temperature. The electrocatalytic investigations reveal that the resultant alloy has an activity of 32.7 mA cm -2 , which is significantly higher than that of Pt/C (17.6 mA cm -2 ) in an alkaline electrolyte and makes it a very efficient electrocatalyst for the ethanol oxidation reaction (EOR). The partial electron transfer from Ag to Pt in Pt-Ag alloy, which weakens the CO binding and poisoning effect on the surface, may be partly responsible for the enhanced catalytic activity of Pt-Ag/C. The activated carbon support also favors charge transport by transferring charge from catalytic active sites to external circuits. The stability and durability studies reveal that Pt-Ag/C performs significantly better than Pt/C, making it a viable electrocatalyst for EOR. Keywords: Direct Ethanol Fuel Cell, Electrochemical Impedance Spectroscopy, Cyclic Voltammetry, Alloy.
由于化石燃料的稀缺性及其严重的环境后果,诸如燃料电池(fc)等高效能量转换装置的发展受到了相当大的关注。活性炭的比能转换效率受电催化剂活性的影响较大。Pt因其高活性和稳定性而被广泛用作电催化剂,但其昂贵的成本和资源的枯竭阻碍了其商业化。在保持Pt电化学性能的同时,通过与一些非贵金属合金化来降低其含量,是Pt实际应用的可行策略之一。在此背景下,我们通过逐步还原过程开发了一种低pt负载的Pt-Ag/C合金电催化剂。采用循环伏安法(CV)、线性扫描伏安法(LSV)、计时伏安法(CA)和电化学阻抗谱法(EIS)在室温下对合成催化剂的电化学性能进行了研究。电催化研究表明,所得合金的电催化活性为32.7 mA cm -2,显著高于Pt/C在碱性电解液中的电催化活性(17.6 mA cm -2),是乙醇氧化反应(EOR)的高效电催化剂。Pt-Ag合金中Ag向Pt的部分电子转移,减弱了CO在表面的结合和中毒效应,可能是Pt-Ag/C催化活性增强的部分原因。活性炭载体也有利于电荷传输,将电荷从催化活性位点转移到外部电路。稳定性和耐久性研究表明,Pt- ag /C的性能明显优于Pt/C,使其成为一种可行的EOR电催化剂。关键词:直接乙醇燃料电池,电化学阻抗法,循环伏安法,合金
{"title":"(Digital Presentation) Ethanol Electro-Oxidation Kinetics Using Activated Carbon-Supported Pt-Ag Catalysts in Alkaline Media","authors":"Sarmistha Baruah, Akshai Kumar, Nageswara Rao Peela","doi":"10.1149/ma2023-01402879mtgabs","DOIUrl":"https://doi.org/10.1149/ma2023-01402879mtgabs","url":null,"abstract":"Due to scarcity of fossil fuels and their severe environmental consequences, the development of high efficiency energy conversion devices such as fuel cells (FCs) have gained considerable attention. The specific energy conversion efficiency of FC is highly influenced by the activity of the electrocatalysts. The Pt is widely used as an electrocatalyst due to its high activity and stability, but its high cost and depletion of resources hinder its commercialization. One of the workable strategies for the practical application of Pt is to reduce its content by alloying with some non-precious metals and simultaneously maintain its electrochemical performance. In this context, we developed a low Pt-loaded Pt-Ag/C alloy electrocatalyst via a gradual reduction process. The electrochemical performance of the as-synthesized catalyst was investigated by cyclic voltammetry (CV), linear sweep voltammetry (LSV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS) using the three-electrode electrochemical workstation at room temperature. The electrocatalytic investigations reveal that the resultant alloy has an activity of 32.7 mA cm -2 , which is significantly higher than that of Pt/C (17.6 mA cm -2 ) in an alkaline electrolyte and makes it a very efficient electrocatalyst for the ethanol oxidation reaction (EOR). The partial electron transfer from Ag to Pt in Pt-Ag alloy, which weakens the CO binding and poisoning effect on the surface, may be partly responsible for the enhanced catalytic activity of Pt-Ag/C. The activated carbon support also favors charge transport by transferring charge from catalytic active sites to external circuits. The stability and durability studies reveal that Pt-Ag/C performs significantly better than Pt/C, making it a viable electrocatalyst for EOR. Keywords: Direct Ethanol Fuel Cell, Electrochemical Impedance Spectroscopy, Cyclic Voltammetry, Alloy.","PeriodicalId":11461,"journal":{"name":"ECS Meeting Abstracts","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135089057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-28DOI: 10.1149/ma2023-01442416mtgabs
Shakul Pathak, Martin Z. Bazant
Electrokinetic phenomena within complex structures are relevant in microfluidics. For example, ion concentration polarization is used for electrokinetic trapping for enhanced biosensing using molecular probes 1 . Concentration polarization near ion-selective membranes also plays an important role in separation systems for desalination 2 . Aside from microfluidics, electrochemical growth-dissolution phenomenon has been reported in lithium ion battery systems where lithium plating and subsequent growth of dendrites can exacerbate the loss of cyclable lithium through the formation of isolated Lithium (i-Li) islands 3 . Initially thought to be “dead”, these islands were shown to migrate from one electrode to the other through a deposition-dissolution mechanism 3 . We present a mathematical solution for the growth and migration of an electrochemically active metal particle in a background current. A broad range of phenomena such as viscous fingering 4 , diffusion-limited aggregation 4 and electrochemical deposition 5 follow Laplacian growth and have been traditionally described using conformal map-dynamics in two dimensions. Some non-Laplacian phenomena like electrochemical transport 6,7 and advection-diffusion-limited aggregation 6 fall into the conformally invariant category 8 and can still be simplified using conformal-mapping techniques. Our solution applies conformal mapping to the non-Laplacian growth of the metal particle to evaluate the role of particle morphology in the evolution of the phase boundary. In addition to migration, dissolution-deposition was found to lead to formation of cusps on the phase boundary under certain conditions. The solution is applicable for a general class of problems with a reactive post or particle in an applied background flux. Analytical solutions such as the one presented here are expected to augment numerical simulations and lead to expressions that capture conditions for the onset of morphological instabilities. References S. Park, B. Sabbagh, R. Abu-Rjal, and G. Yossifon, Lab Chip , 22 , 814–825 (2022) https://pubs.rsc.org/en/content/articlehtml/2022/lc/d1lc00864a. D. Deng et al., Desalination , 357 , 77–83 (2015). F. Liu et al., Nature 2021 600:7890 , 600 , 659–663 (2021) https://www.nature.com/articles/s41586-021-04168-w. J. Mathiesen, I. Procaccia, H. L. Swinney, and M. Thrasher, Europhys Lett , 76 , 257 (2006) https://iopscience.iop.org/article/10.1209/epl/i2006-10246-x. D. A. Kessler, J. Koplik, and H. Levine, http://dx.doi.org/10.1080/00018738800101379 , 37 , 255–339 (2006) https://www.tandfonline.com/doi/abs/10.1080/00018738800101379. M. Z. Bazant, J. Choi, and B. Davidovitch, Phys Rev Lett , 91 , 045503 (2003) https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.91.045503. Z. Gu et al., Phys Rev Fluids , 7 , 033701 (2022) https://journals.aps.org/prfluids/abstract/10.1103/PhysRevFluids.7.033701. M. Z. Bazant, Proceedings of the Royal Society of London. Series A: Mathematical, Physical and Engine
复杂结构中的电动力学现象与微流体有关。例如,离子浓度极化用于利用分子探针增强生物传感的电动捕获1。离子选择膜附近的浓度极化在脱盐分离系统中也起着重要作用。除了微流体外,在锂离子电池系统中也有电化学生长-溶解现象的报道,其中锂电镀和随后的枝晶生长可以通过形成孤立的锂(i-Li)岛而加剧可循环锂的损失3。这些岛最初被认为是“死的”,但它们通过沉积-溶解机制从一个电极迁移到另一个电极。我们提出了电化学活性金属粒子在背景电流中生长和迁移的数学解。广泛的现象,如粘指动、扩散受限聚集和电化学沉积,都遵循拉普拉斯生长,传统上使用二维保角映射动力学来描述。一些非拉普拉斯现象,如电化学输运6,7和平流-扩散-有限聚集6,属于共形不变的类别8,仍然可以使用共形映射技术进行简化。我们的解决方案将保角映射应用于金属颗粒的非拉普拉斯生长,以评估颗粒形态在相边界演化中的作用。除了迁移外,在一定条件下,溶解-沉积还会导致相界上形成尖点。该解决方案适用于在施加的背景通量中具有活性柱或粒子的一般类型的问题。本文中提出的解析解有望增强数值模拟,并得出能够捕捉形态不稳定发生条件的表达式。参考文献S. Park, B. Sabbagh, R. Abu-Rjal和G. Yossifon, Lab Chip, 22,814 - 825 (2022) https://pubs.rsc.org/en/content/articlehtml/2022/lc/d1lc00864a。邓丹等,海水淡化,357,77-83(2015)。刘峰等,自然科学学报,2021,600,659-663 (2021)https://www.nature.com/articles/s41586-021-04168-w。J. Mathiesen, I. Procaccia, H. L. Swinney, M. Thrasher, Europhys, 76, 257 (2006) https://iopscience.iop.org/article/10.1209/epl/i2006-10246-x。D. A. Kessler, J. Koplik和H. Levine, http://dx.doi.org/10.1080/00018738800101379, 37, 255-339 (2006) https://www.tandfonline.com/doi/abs/10.1080/00018738800101379。M. Z. Bazant, J. Choi, B. Davidovitch,物理学报,91,045503 (2003)https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.91.045503。古中等,物理学报,7,033701 (2022)https://journals.aps.org/prfluids/abstract/10.1103/PhysRevFluids.7.033701。m.z. Bazant,《伦敦皇家学会学报》。A辑:数学、物理与工程科学,460,1433-1452 (2004)https://royalsocietypublishing.org/doi/10.1098/rspa.2003.1218。
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Pub Date : 2023-08-28DOI: 10.1149/ma2023-0154134mtgabs
Hangyue Li, Minfang Han
Solid Oxide Fuel Cell (SOFC) is a developing energy conversion technology featuring high efficiency, power density, durability, and fuel compatibility. With these advantages, SOFCs are combined frequently with heat engines such as gas turbines, for higher system efficiency and power density. In practice, SOFCs are often required to deliver certain power. Considering economical aspects, power generation efficiency is critical to the running cost of energy conversion systems. However, high power and high efficiency are likely reached under different operating conditions. For example, to meet peak power demands, higher operating currents and fuel flowrates are necessary, while SOFCs are generally more energy efficient at lower current densities and fuel flowrates. Hence, the ideal operating condition is the solution to a power-constrained efficiency optimization problem. Moreover, SOFCs degrade as they operate, introducing gradual changes to SOFC characteristics. Thus, the optimization needs to be solved dynamically. To analyze the above-mentioned problem, a 10 cm by 10 cm planar SOFC was repeatedly tested for polarization characterizations and electrochemical impedance spectra. A 2-dimentional multi-physics model was developed and calibrated using both polarization and impedance data. To account for the lower open circuit voltage at lower fuel flowrates, an equivalent leakage current is included in the model. The model was thereafter employed for efficiency optimization given power constraints. At each required power output, the optimal fuel flowrate and the corresponding voltage, current, and efficiency was calculated. The electrical efficiency peaks globally at around 0.1 Standard Liter per Minute (SLM) hydrogen flowrate, while at higher power, the optimal efficiency is reached at fuel utilizations between 65% and 90%. Accounting for degradation in terms of growing ohmic resistance and decreasing electrode exchange current densities, the optimal efficiency is reached at lowering fuel utilization and lowering voltage, which may result in local oxidization of the anode. Moreover, an easy and straight-forward way was proposed to estimate the optimal fuel flowrate given polarization data. Further studies involving the safety constraints will be carried out in the future. Figure 1
固体氧化物燃料电池(SOFC)是一种新兴的能量转换技术,具有高效率、功率密度高、耐久性好和燃料相容性好等特点。由于这些优点,sofc经常与燃气轮机等热机结合使用,以提高系统效率和功率密度。在实践中,sofc通常需要提供一定的功率。从经济性角度考虑,发电效率是影响能源转换系统运行成本的关键因素。然而,在不同的运行条件下,有可能达到高功率和高效率。例如,为了满足峰值功率需求,需要更高的工作电流和燃料流量,而sofc通常在较低的电流密度和燃料流量下更节能。因此,理想的运行状态是解决功率受限的效率优化问题。此外,SOFC在运行过程中会降解,从而导致SOFC特性的逐渐变化。因此,优化需要动态求解。为了分析上述问题,对一个10 cm × 10 cm的平面SOFC进行了反复极化表征和电化学阻抗谱测试。利用极化和阻抗数据建立了二维多物理场模型并进行了标定。为了考虑在较低燃油流量下较低的开路电压,模型中包含了一个等效泄漏电流。在给定功率约束条件下,利用该模型进行效率优化。在每个所需功率输出下,计算最佳燃油流量以及相应的电压、电流和效率。在全球范围内,电效率在0.1标准升/分钟(SLM)氢气流量时达到峰值,而在更高功率下,燃油利用率在65%至90%之间达到最佳效率。考虑到欧姆电阻的增加和电极交换电流密度的降低,在降低燃料利用率和降低电压时达到最佳效率,这可能导致阳极局部氧化。此外,在给定极化数据的情况下,提出了一种简单、直接的最优燃油流量估计方法。有关安全限制的进一步研究将在未来进行。图1
{"title":"Efficiency Optimization of SOFC Subject to Degradation and Minimum Power Constraint","authors":"Hangyue Li, Minfang Han","doi":"10.1149/ma2023-0154134mtgabs","DOIUrl":"https://doi.org/10.1149/ma2023-0154134mtgabs","url":null,"abstract":"Solid Oxide Fuel Cell (SOFC) is a developing energy conversion technology featuring high efficiency, power density, durability, and fuel compatibility. With these advantages, SOFCs are combined frequently with heat engines such as gas turbines, for higher system efficiency and power density. In practice, SOFCs are often required to deliver certain power. Considering economical aspects, power generation efficiency is critical to the running cost of energy conversion systems. However, high power and high efficiency are likely reached under different operating conditions. For example, to meet peak power demands, higher operating currents and fuel flowrates are necessary, while SOFCs are generally more energy efficient at lower current densities and fuel flowrates. Hence, the ideal operating condition is the solution to a power-constrained efficiency optimization problem. Moreover, SOFCs degrade as they operate, introducing gradual changes to SOFC characteristics. Thus, the optimization needs to be solved dynamically. To analyze the above-mentioned problem, a 10 cm by 10 cm planar SOFC was repeatedly tested for polarization characterizations and electrochemical impedance spectra. A 2-dimentional multi-physics model was developed and calibrated using both polarization and impedance data. To account for the lower open circuit voltage at lower fuel flowrates, an equivalent leakage current is included in the model. The model was thereafter employed for efficiency optimization given power constraints. At each required power output, the optimal fuel flowrate and the corresponding voltage, current, and efficiency was calculated. The electrical efficiency peaks globally at around 0.1 Standard Liter per Minute (SLM) hydrogen flowrate, while at higher power, the optimal efficiency is reached at fuel utilizations between 65% and 90%. Accounting for degradation in terms of growing ohmic resistance and decreasing electrode exchange current densities, the optimal efficiency is reached at lowering fuel utilization and lowering voltage, which may result in local oxidization of the anode. Moreover, an easy and straight-forward way was proposed to estimate the optimal fuel flowrate given polarization data. Further studies involving the safety constraints will be carried out in the future. Figure 1","PeriodicalId":11461,"journal":{"name":"ECS Meeting Abstracts","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135089082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
All-inorganic halide perovskites (HPs) continue to be of current interest for light source applications (e.g. lasers, LED’s) because of their high emission quantum yields and wide wavelength tunability due to compositional engineering [1]. The development of red and near-IR emitting lead halide perovskites, however, has been hampered by low emission efficiency and instability of iodine based compositions at room temperature. Recent studies employing transition metal or lanthanide doping have demonstrated an alternative approach to achieve red and near-IR emitting HPs structures [2-4]. In this study we report results of the mechano-chemical synthesis of undoped and manganese (Mn) doped CsPb(Br 1-x Cl x ) 3 halide perovskites as emitting materials for light source development. Mechano-chemical synthesis is considered a green chemistry method avoiding the use of complex and time-consuming reactions, energetic-enabled conditions, expensive precursor sources, and hazardous reagents, catalysts, additives, and surfactants. Mechano-chemical synthesis experiments were performed employing a high energy ball-mill and 5N purity lead halide and cesium halide powders. The prepared HPs were evaluated by optical microscopy, SEM, TEM, XRD, and fluorometric measurements. Under UV optical excitation a Mn doped CsPbCl 3 sample exhibited a broad red emission band centers at ~615nm, which was slightly red-shifted compared to the emission from a melt-grown Mn: CsPbCl 3 crystals (see Figure 1). Post synthesis optimization strategies for HPs were also explored including thermal treatment, high-pressure studies, and solvent dependency. Comparative studies of the emission properties of undoped and Mn doped CsPb(Br 1-x Cl x ) 3 prepared by mechano-chemical synthesis, microwave-assisted synthesis, and melt-synthesis will also be presented. Acknowledgment This work was supported by the Army Research Office (grant W911NF1810447) and National Science Foundation (grant NSF-DMR 1827820-PREM). References [1] R. Babu, L. Giribabu, S. P. Singh, "Recent Advances in Halide-Based Perovskite Crystals and Their Optoelectronic Applications", Cryst. Growth Des. 18, 2645 (2018). [2] B. Su, G. Zhou, J. Huang, E. Song, A, Nag, Z. Xia, “Mn 2+ doped metal halide perovskites: structure photoluminescence, and applications”, Laser and Photonics Reviews, 15, 2000334 (2021). [3] U. Hommerich, J. Barnett, A. Kabir, K. Ghebreyessus, K. Hampton, S. Uba, I. Uba, D. Geddis, C. Yang, S.B. Trivedi, S. Fraden, A. Aghvami, "Comparative steady-state and time-resolved emission spectroscopy of Mn doped CsPbCl 3 perovskites nanoparticles and bulk single crystals for photonic applications ", SPIE Proceedings Volume 11682, Optical Components and Materials XVIII, 116821J (2021). [4] U. Hömmerich, D. Hart, A. Kabir, C. Yang, S. B. Trivedi, "Materials development and mid-infrared emission properties of Dy-doped TlPb 2 Br 5 and CsPbCl 3 ," Proc. SPIE 11276, Optical Components and Materials XVII, 112761D (2020). Figure
全无机卤化物钙钛矿(HPs)由于其高发射量子产率和宽波长可调性(由于成分工程[1])而继续成为光源应用(例如激光,LED)的兴趣。然而,红外和近红外卤化铅钙钛矿的开发一直受到发射效率低和碘基成分在室温下不稳定的阻碍。最近的研究使用过渡金属或镧系元素掺杂已经证明了一种替代方法来实现红色和近红外发射的hp结构[2-4]。在本研究中,我们报告了机械化学合成未掺杂和锰(Mn)掺杂CsPb(Br 1-x Cl x) 3卤化物钙钛矿作为光源开发发射材料的结果。机械化学合成被认为是一种绿色化学方法,避免使用复杂和耗时的反应,能量使能的条件,昂贵的前体来源和危险的试剂,催化剂,添加剂和表面活性剂。采用高能球磨机和5N纯度的卤化铅和卤化铯粉体进行了机械化学合成实验。通过光学显微镜、扫描电镜、透射电镜、x射线衍射和荧光测量对制备的hp进行了评价。在紫外光激发下,Mn掺杂的CsPbCl 3样品在~615nm处显示出较宽的红色发射带中心,与熔融生长的Mn: CsPbCl 3晶体的发射相比略有红移(见图1)。此外,还探索了HPs的合成后优化策略,包括热处理、高压研究和溶剂依赖性。对机械化学合成、微波辅助合成和熔融合成制备的未掺杂和Mn掺杂CsPb(Br 1-x Cl x) 3的发射特性进行了比较研究。这项工作得到了美国陆军研究办公室(grant W911NF1810447)和美国国家科学基金会(grant NSF-DMR 1827820-PREM)的支持。R. Babu, L. Giribabu, S. P. Singh,“基于卤化物的钙钛矿晶体及其光电应用的最新进展”,crystal。成长学报,18,2645(2018)。[10]苏斌,周国光,黄建军,宋恩恩,夏忠,“Mn - 2+掺杂金属卤化物钙钛矿的结构光致发光及其应用”,激光与光子学报,15,2000,34(2021)。[10] U. Hommerich, J. Barnett, A. Kabir, K. Ghebreyessus, K. Hampton, S. Uba, I. Uba, D. Geddis, C. Yang, S.B. Trivedi, S. Fraden, A. Aghvami,“Mn掺杂CsPbCl 3钙钛矿纳米粒子和体单晶在光子应用中的比较稳态和时间分辨发射光谱”,SPIE学报vol . 11682,光学元件与材料XVIII, 116821J(2021)。[4]美国Hommerich d·哈特,a . Kabir c, s . b . Trivedi”材料的发展和中红外发射特性Dy-doped TlPb 2 Br 5和CsPbCl 3,“Proc。相比11276年,光学组件和材料十七、112761 d(2020)。图1
{"title":"Mechano-Chemical Synthesis and Characterization of Undoped and Mn<sup>2+</sup> Doped Cspb(Br<sub>1-x</sub>Cl<sub>x</sub>)<sub>3</sub> Halide Perovskite for Light Source Application","authors":"Ivy Krystal Jones, Uwe Hommerich, Kesete Ghebreyessus, Vadivel Jagasivamani, Demetris Geddis, Kabir Al Amin, Sudhir Trivedi, Amanda Tiano, Seth Fraden, Amir Moore, Khalid Hampton","doi":"10.1149/ma2023-01321827mtgabs","DOIUrl":"https://doi.org/10.1149/ma2023-01321827mtgabs","url":null,"abstract":"All-inorganic halide perovskites (HPs) continue to be of current interest for light source applications (e.g. lasers, LED’s) because of their high emission quantum yields and wide wavelength tunability due to compositional engineering [1]. The development of red and near-IR emitting lead halide perovskites, however, has been hampered by low emission efficiency and instability of iodine based compositions at room temperature. Recent studies employing transition metal or lanthanide doping have demonstrated an alternative approach to achieve red and near-IR emitting HPs structures [2-4]. In this study we report results of the mechano-chemical synthesis of undoped and manganese (Mn) doped CsPb(Br 1-x Cl x ) 3 halide perovskites as emitting materials for light source development. Mechano-chemical synthesis is considered a green chemistry method avoiding the use of complex and time-consuming reactions, energetic-enabled conditions, expensive precursor sources, and hazardous reagents, catalysts, additives, and surfactants. Mechano-chemical synthesis experiments were performed employing a high energy ball-mill and 5N purity lead halide and cesium halide powders. The prepared HPs were evaluated by optical microscopy, SEM, TEM, XRD, and fluorometric measurements. Under UV optical excitation a Mn doped CsPbCl 3 sample exhibited a broad red emission band centers at ~615nm, which was slightly red-shifted compared to the emission from a melt-grown Mn: CsPbCl 3 crystals (see Figure 1). Post synthesis optimization strategies for HPs were also explored including thermal treatment, high-pressure studies, and solvent dependency. Comparative studies of the emission properties of undoped and Mn doped CsPb(Br 1-x Cl x ) 3 prepared by mechano-chemical synthesis, microwave-assisted synthesis, and melt-synthesis will also be presented. Acknowledgment This work was supported by the Army Research Office (grant W911NF1810447) and National Science Foundation (grant NSF-DMR 1827820-PREM). References [1] R. Babu, L. Giribabu, S. P. Singh, \"Recent Advances in Halide-Based Perovskite Crystals and Their Optoelectronic Applications\", Cryst. Growth Des. 18, 2645 (2018). [2] B. Su, G. Zhou, J. Huang, E. Song, A, Nag, Z. Xia, “Mn 2+ doped metal halide perovskites: structure photoluminescence, and applications”, Laser and Photonics Reviews, 15, 2000334 (2021). [3] U. Hommerich, J. Barnett, A. Kabir, K. Ghebreyessus, K. Hampton, S. Uba, I. Uba, D. Geddis, C. Yang, S.B. Trivedi, S. Fraden, A. Aghvami, \"Comparative steady-state and time-resolved emission spectroscopy of Mn doped CsPbCl 3 perovskites nanoparticles and bulk single crystals for photonic applications \", SPIE Proceedings Volume 11682, Optical Components and Materials XVIII, 116821J (2021). [4] U. Hömmerich, D. Hart, A. Kabir, C. Yang, S. B. Trivedi, \"Materials development and mid-infrared emission properties of Dy-doped TlPb 2 Br 5 and CsPbCl 3 ,\" Proc. SPIE 11276, Optical Components and Materials XVII, 112761D (2020). Figure","PeriodicalId":11461,"journal":{"name":"ECS Meeting Abstracts","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135089106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-28DOI: 10.1149/ma2023-0154113mtgabs
Katherine Develos Bagarinao, Ozden Celikbilek, Gwilherm Kerherve, Sarah Fearn, Stephen J Skinner, Haruo Kishimoto
Nanostructured La 0.6 Sr 0.4 CoO 3-δ (LSC) thin film electrodes exhibit exceptionally high oxygen surface exchange properties, surpassing those of conventional microscale electrode structures, which are desirable for application in solid oxide cells (SOC) [1-2]. On the other hand, the LSC nanostructures also tend to undergo significant morphological changes at typically high temperatures required for SOC operation, leading to rapid degradation in performance. Here, towards the goal of improving the long-term stability of electrochemical performance of nanostructured LSC thin films, a systematic investigation of the effect of processing temperatures on long-term stability was carried out [3]. By varying the deposition temperature (500 °C to room temperature), the as-grown characteristic nanostructures of LSC thin films prepared using pulsed laser deposition can be tuned from highly dense nanocolumnar grains to nanofibrous structures with high porosity. Variations in the deposition temperature also resulted to differences in the proportion of surface-bound/lattice-bound Sr and Co 2+ /Co 3+ at the surfaces of the as-grown LSC thin films; however, prolonged annealing at 700 °C in air essentially transforms the surfaces to a final state with mostly lattice-bound Sr and Co 3+ . Nevertheless, LSC films with initially nanofibrous structures are found to be less prone to the grain sintering effect occurring at high temperatures and exhibit less degradation of the electrode polarization resistance as compared to well-dense films. Using lower deposition temperatures, cation interdiffusion occurring at LSC/GDC interfaces is also significantly suppressed, thus leading to better interfacial stability as compared to those prepared at higher deposition temperatures. These results highlight the relationship between characteristic nanostructures of thin film electrodes and electrochemical performance and provide guidance on designing electrodes with improved long-term stability. [1] J. Januschewsky, M. Ahrens, A. Opitz, F. Kubel and J. Fleig, Adv. Funct. Mater., 2009, 19, 3151–3156. [2] J. Hayd, L. Dieterle, U. Guntow, D. Gerthsen and E. Ivers-Tiffee, J. Power Sources, 2011, 196, 7263–7270. [3] K. Develos-Bagarinao, O. Celikbilek, R. A. Budiman, G. Kerherve, S. Fearn, S. J. Skinner and H. Kishimoto, J. Mater. Chem. A, 10, 2445-2459 (2022).
纳米结构的La 0.6 Sr 0.4 CoO 3-δ (LSC)薄膜电极表现出异常高的氧表面交换性能,超越了传统的微尺度电极结构,这是固体氧化物电池(SOC)应用的理想选择[1-2]。另一方面,在SOC工作所需的高温下,LSC纳米结构也会发生显著的形态变化,导致性能迅速下降。本文以提高纳米结构LSC薄膜电化学性能的长期稳定性为目标,系统地研究了加工温度对长期稳定性的影响。通过改变沉积温度(500℃至室温),脉冲激光沉积制备的LSC薄膜的生长特征纳米结构可以从高密度的纳米柱状颗粒调整到具有高孔隙率的纳米纤维结构。沉积温度的变化也导致生长LSC薄膜表面结合/晶格结合的Sr和Co 2+ /Co 3+比例的差异;然而,在空气中700℃的长时间退火基本上使表面转变为主要由晶格结合的Sr和Co 3+组成的最终状态。然而,与致密薄膜相比,具有初始纳米纤维结构的LSC薄膜在高温下不易发生晶粒烧结效应,电极极化电阻的退化程度也较低。在较低的沉积温度下,LSC/GDC界面上发生的阳离子相互扩散也被显著抑制,因此与在较高沉积温度下制备的材料相比,界面稳定性更好。这些结果突出了薄膜电极的特征纳米结构与电化学性能之间的关系,并为设计具有更好长期稳定性的电极提供了指导。[10] J. Januschewsky, M. Ahrens, A. Opitz, F. Kubel, J. Fleig, ad . Funct。板牙。中国农业科学,2009,19,3151-3156。[10]刘建军,刘建军,刘建军,等。能源工程学报,2011,26(1):1 - 7。[10] K. Develos-Bagarinao, O. Celikbilek, R. A. Budiman, G. Kerherve, S. Fearn, S. J. Skinner, H.岸本,J. Mater。化学。[j] .农业工程学报,2016,33(2):445- 459(2022)。
{"title":"Nanostructured LSC Thin Film Electrodes with Improved Electrochemical Performance and Long-Term Stability","authors":"Katherine Develos Bagarinao, Ozden Celikbilek, Gwilherm Kerherve, Sarah Fearn, Stephen J Skinner, Haruo Kishimoto","doi":"10.1149/ma2023-0154113mtgabs","DOIUrl":"https://doi.org/10.1149/ma2023-0154113mtgabs","url":null,"abstract":"Nanostructured La 0.6 Sr 0.4 CoO 3-δ (LSC) thin film electrodes exhibit exceptionally high oxygen surface exchange properties, surpassing those of conventional microscale electrode structures, which are desirable for application in solid oxide cells (SOC) [1-2]. On the other hand, the LSC nanostructures also tend to undergo significant morphological changes at typically high temperatures required for SOC operation, leading to rapid degradation in performance. Here, towards the goal of improving the long-term stability of electrochemical performance of nanostructured LSC thin films, a systematic investigation of the effect of processing temperatures on long-term stability was carried out [3]. By varying the deposition temperature (500 °C to room temperature), the as-grown characteristic nanostructures of LSC thin films prepared using pulsed laser deposition can be tuned from highly dense nanocolumnar grains to nanofibrous structures with high porosity. Variations in the deposition temperature also resulted to differences in the proportion of surface-bound/lattice-bound Sr and Co 2+ /Co 3+ at the surfaces of the as-grown LSC thin films; however, prolonged annealing at 700 °C in air essentially transforms the surfaces to a final state with mostly lattice-bound Sr and Co 3+ . Nevertheless, LSC films with initially nanofibrous structures are found to be less prone to the grain sintering effect occurring at high temperatures and exhibit less degradation of the electrode polarization resistance as compared to well-dense films. Using lower deposition temperatures, cation interdiffusion occurring at LSC/GDC interfaces is also significantly suppressed, thus leading to better interfacial stability as compared to those prepared at higher deposition temperatures. These results highlight the relationship between characteristic nanostructures of thin film electrodes and electrochemical performance and provide guidance on designing electrodes with improved long-term stability. [1] J. Januschewsky, M. Ahrens, A. Opitz, F. Kubel and J. Fleig, Adv. Funct. Mater., 2009, 19, 3151–3156. [2] J. Hayd, L. Dieterle, U. Guntow, D. Gerthsen and E. Ivers-Tiffee, J. Power Sources, 2011, 196, 7263–7270. [3] K. Develos-Bagarinao, O. Celikbilek, R. A. Budiman, G. Kerherve, S. Fearn, S. J. Skinner and H. Kishimoto, J. Mater. Chem. A, 10, 2445-2459 (2022).","PeriodicalId":11461,"journal":{"name":"ECS Meeting Abstracts","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135089114","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-28DOI: 10.1149/ma2023-015477mtgabs
Saad Waseem, Matthew Barre, Katarzyna Sabolsky, Richard Hart, Seunghyuck Hong, Edward Sabolsky
Implementation of nano-catalyst materials into solid oxide fuel cell (SOFC) electrodes to improve performance and stability has been widely studied. Addition of the nano-catalysts into an electrode structure serves to enhance the electrochemical performance of the SOFC by increasing the Triple Phase Boundary (TPB) area, improving redox stabilization, and modifying reaction kinetics of hydrocarbon gasses that cause anode degradation due to carbon deposition. SOFCs operating upstream of a reformer need to exhibit good tolerance to any hydrocarbon components that may make their way to the stack. Typical Ni-based cermet anodes suffer from anode deactivation due to carbon build up under hydrocarbon flows. Carbon builds up and covers the TPB area which results in poor electrochemical performance. Larger carbon deposits can block pores within the anode microstructure which leads to gas diffusion issues. Carbon buildup also causes mechanical stresses to the electrode due to volumetric changes which can lead to fracture and complete failure of the cell. This work studied nano-catalyst decoration of the Ni-based cermet anodes with catalysts that promote internal reforming to protect against coking. Addition of active metal components (such as Co, Ge, Sn), and ceramic reforming promoters (such as CeO 2 , MgO) were investigated. Multi-component systems with several catalysts were also examined. Uniform incorporation of nano-catalyst into the anode microstructure was achieved through a patented liquid phase surfactant assisted process (using various catechol surfactants). Deposition loading densities and distribution of nanoparticles was controlled by altering the surfactant and catalyst solution concentrations. Nano-catalyst depositions were characterized through Scanning Electron Microscope (SEM) for imaging, Atomic Force Microscopy (AFM) for topographical analysis, and Energy-Dispersive X-ray Spectroscopy (EDS) for chemical characterization. Figure 1 shows SEM imaging of nano catalyst distribution of cerium oxide (CeO 2 ) and cobalt oxide (CoO) co-deposition within an anode structure. A uniform distribution of nano-sized catalyst materials is observed. Accelerated evaluation of nano-catalysts for SOFCs was completed through symmetrical anode tests, where a symmetrical anode cell was subjected to hydrocarbon impurity at SOFC operating temperatures and electrochemical impedance spectroscopy (EIS) characterization was done over time. The best catalyst systems were down selected and long-term SOFC tests were completed with current-voltage-power (I-V-P) and EIS evaluation. Post-mortem microstructure and chemistry characterizations were also used in analysis. Uniform nano catalyst distribution of CeO 2 and CoO within the anode structure demonstrated greater than 50% sustained improvement in harsh environment, long-term tests where the cell was subjected to 40% CH 4 for 50+ h. Figure 1
{"title":"Metal Composite Nano-Catalyst Enhanced Solid Oxide Fuel Cell Anodes for Improved Performance and Stability with Hydrocarbon Containing Fuels","authors":"Saad Waseem, Matthew Barre, Katarzyna Sabolsky, Richard Hart, Seunghyuck Hong, Edward Sabolsky","doi":"10.1149/ma2023-015477mtgabs","DOIUrl":"https://doi.org/10.1149/ma2023-015477mtgabs","url":null,"abstract":"Implementation of nano-catalyst materials into solid oxide fuel cell (SOFC) electrodes to improve performance and stability has been widely studied. Addition of the nano-catalysts into an electrode structure serves to enhance the electrochemical performance of the SOFC by increasing the Triple Phase Boundary (TPB) area, improving redox stabilization, and modifying reaction kinetics of hydrocarbon gasses that cause anode degradation due to carbon deposition. SOFCs operating upstream of a reformer need to exhibit good tolerance to any hydrocarbon components that may make their way to the stack. Typical Ni-based cermet anodes suffer from anode deactivation due to carbon build up under hydrocarbon flows. Carbon builds up and covers the TPB area which results in poor electrochemical performance. Larger carbon deposits can block pores within the anode microstructure which leads to gas diffusion issues. Carbon buildup also causes mechanical stresses to the electrode due to volumetric changes which can lead to fracture and complete failure of the cell. This work studied nano-catalyst decoration of the Ni-based cermet anodes with catalysts that promote internal reforming to protect against coking. Addition of active metal components (such as Co, Ge, Sn), and ceramic reforming promoters (such as CeO 2 , MgO) were investigated. Multi-component systems with several catalysts were also examined. Uniform incorporation of nano-catalyst into the anode microstructure was achieved through a patented liquid phase surfactant assisted process (using various catechol surfactants). Deposition loading densities and distribution of nanoparticles was controlled by altering the surfactant and catalyst solution concentrations. Nano-catalyst depositions were characterized through Scanning Electron Microscope (SEM) for imaging, Atomic Force Microscopy (AFM) for topographical analysis, and Energy-Dispersive X-ray Spectroscopy (EDS) for chemical characterization. Figure 1 shows SEM imaging of nano catalyst distribution of cerium oxide (CeO 2 ) and cobalt oxide (CoO) co-deposition within an anode structure. A uniform distribution of nano-sized catalyst materials is observed. Accelerated evaluation of nano-catalysts for SOFCs was completed through symmetrical anode tests, where a symmetrical anode cell was subjected to hydrocarbon impurity at SOFC operating temperatures and electrochemical impedance spectroscopy (EIS) characterization was done over time. The best catalyst systems were down selected and long-term SOFC tests were completed with current-voltage-power (I-V-P) and EIS evaluation. Post-mortem microstructure and chemistry characterizations were also used in analysis. Uniform nano catalyst distribution of CeO 2 and CoO within the anode structure demonstrated greater than 50% sustained improvement in harsh environment, long-term tests where the cell was subjected to 40% CH 4 for 50+ h. Figure 1","PeriodicalId":11461,"journal":{"name":"ECS Meeting Abstracts","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135089130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-28DOI: 10.1149/ma2023-0154103mtgabs
Giuseppe Sassone, Eduardo Da Rosa Silva, Manon Prioux, Maxime Hubert, Bertrand Morel, Aline Léon, Jérôme Laurencin
Solid Oxide Cells (SOCs) are high temperature energy-conversion devices which have attracted a growing interest in the recent years. Indeed, this technology presents a high efficiency and a good reversibility in fuel cell (SOFC) and electrolysis (SOEC) modes. Thanks to its flexibility, SOCs can offer technical solutions for the development of a clean hydrogen economy. Nevertheless, SOCs durability is still insufficient for large scale commercialization. Therefore, it is still required to improve the SOCs lifetime by maintaining high performances. For this purpose, it is necessary to better understand the impact of global operating conditions on the local processes taking place in the cell components. Besides, the role of the electrode microstructure on the reaction mechanism is still not precisely understood. From this point of view, the modelling can be an efficient tool to unravel and better analyze all the microscopic processes involved in the cell operation. In this context, a physical-based model has been proposed to investigate the impact of operating conditions on the electrodes reaction mechanisms and cell performances. This model takes into account (i) a 3D representation of the electrode microstructure [1], (ii) a description of the reaction mechanisms in full elementary steps [2,3] and (iii) the SOC geometry with the gas flow configuration [4,5]. This multiscale model has been developed considering a typical cell composed of a dense electrolyte in Y 0.148 Zr 0.852 O 1.926 (8YSZ) sandwiched between an O 2 electrode in La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3- d -Ce 0.8 Gd 0.2 O 2-δ (LSCF-GDC) and an H 2 electrode made of Ni and YSZ (Ni-YSZ). The model has been validated using a specific experimental setup which was developed to measure the local polarization curves along the cell length. For this purpose, a specific design of the interconnect has been proposed in order to probe the local current density on the standard studied cells (Fig. 1a) [6]. It has been found that the model is able to reproduce accurately the global and local polarizations curves in SOFC and SOEC modes (Fig. 1a and 1b). The stationary model has been also extended to compute electrochemical impedance spectra by keeping the full description of the reaction mechanisms in elementary steps. This dynamic model, which is able to compute the impedance diagrams at Open Circuit Voltage (OCV) and under polarization, has been compared to the experimental data. As shown in Fig. 1c and 1d, a reasonable agreement has been found between the measurements and the simulations without any fitting. The validated stationary and dynamic model has been used to analyze the cell operation in electrolysis and fuel cell modes. The activated reaction pathways associated with the elementary steps in the active layers have been investigated depending on the position along the cell length. The different contributions arising in the impedance spectra have been also identified and discussed. References [1]
固体氧化物电池(SOCs)是近年来备受关注的高温能量转换器件。事实上,该技术在燃料电池(SOFC)和电解(SOEC)模式下表现出高效率和良好的可逆性。由于其灵活性,soc可以为清洁氢经济的发展提供技术解决方案。然而,soc的耐用性仍不足以实现大规模商业化。因此,仍然需要通过保持高性能来提高soc的使用寿命。为此,有必要更好地了解全局操作条件对单元组件中发生的局部过程的影响。此外,电极微观结构对反应机理的作用仍不明确。从这个角度来看,建模可以是一个有效的工具来解开和更好地分析细胞操作中涉及的所有微观过程。在此背景下,提出了一个基于物理的模型来研究操作条件对电极反应机制和电池性能的影响。该模型考虑了(i)电极微观结构[1]的3D表示,(ii)完整基本步骤反应机制的描述[2,3]和(iii)带有气体流动配置的SOC几何形状[4,5]。该多尺度模型考虑了一个典型的电池,该电池由y0.148 Zr 0.852 O 1.926 (8YSZ)的致密电解质夹在La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3- d - ce 0.8 Gd 0.2 O 2-δ (LSCF-GDC)和Ni和YSZ (Ni-YSZ)组成的h2电极组成。该模型已通过一个特定的实验装置进行了验证,该装置是用来测量沿电池长度的局部极化曲线的。为此,提出了一种特定的互连设计,以探测所研究的标准电池上的局部电流密度(图1a)[6]。研究发现,该模型能够准确再现SOFC和SOEC模式下的全局和局部极化曲线(图1a和1b)。通过保持反应机理在基本步骤的完整描述,平稳模型也被扩展到计算电化学阻抗谱。该动态模型能够计算开路电压和极化下的阻抗图,并与实验数据进行了比较。如图1c和1d所示,在没有任何拟合的情况下,测量结果与模拟结果之间存在合理的一致性。并利用已验证的稳态和动态模型对电解和燃料电池模式下的电池运行进行了分析。与活性层中基本步骤相关的活化反应途径已根据沿细胞长度的位置进行了研究。对阻抗谱中产生的不同贡献也进行了识别和讨论。参考文献[10]H. Moussaoui, J. Laurencin, Y. Gavet, G. Delette, M. Hubert, P. Cloetens, T. Le Bihan, J. Debayle,计算材料科学,43(2018):262-276。[10] E. Effori, J. Laurencin, E. Da Rosa Silva, M. Hubert, T. David, M. Petitjean, G. Geneste, L. desemond, E. Siebert, J. Electrochem。Soc。, 168(2021) 044520。bb1 F. Monaco, E. Effori, M. Hubert, E. Siebert, G. Geneste, B. Morel, E. Djurado, D. Montinaro, J. Laurencin,电化学学报389 (2021)138765 bb1 L. Bernadet, J. Laurencin, G. Roux, F. Mauvy, M. Reytier,电化学学报253(2017)114-127。[10] J. Laurencin, D. Kane, G. Delette, J. Deseure, F. Lefebvre-Joud, J.电源,1996(2011):2080-2093。[10]李建军,李建军,李建军,等。能源与环境工程学报,2004,12(2):444 - 444。图1
{"title":"Multiscale Modelling of Solid Oxide Cells Validated on Electrochemical Impedance Spectra and Polarization Curves","authors":"Giuseppe Sassone, Eduardo Da Rosa Silva, Manon Prioux, Maxime Hubert, Bertrand Morel, Aline Léon, Jérôme Laurencin","doi":"10.1149/ma2023-0154103mtgabs","DOIUrl":"https://doi.org/10.1149/ma2023-0154103mtgabs","url":null,"abstract":"Solid Oxide Cells (SOCs) are high temperature energy-conversion devices which have attracted a growing interest in the recent years. Indeed, this technology presents a high efficiency and a good reversibility in fuel cell (SOFC) and electrolysis (SOEC) modes. Thanks to its flexibility, SOCs can offer technical solutions for the development of a clean hydrogen economy. Nevertheless, SOCs durability is still insufficient for large scale commercialization. Therefore, it is still required to improve the SOCs lifetime by maintaining high performances. For this purpose, it is necessary to better understand the impact of global operating conditions on the local processes taking place in the cell components. Besides, the role of the electrode microstructure on the reaction mechanism is still not precisely understood. From this point of view, the modelling can be an efficient tool to unravel and better analyze all the microscopic processes involved in the cell operation. In this context, a physical-based model has been proposed to investigate the impact of operating conditions on the electrodes reaction mechanisms and cell performances. This model takes into account (i) a 3D representation of the electrode microstructure [1], (ii) a description of the reaction mechanisms in full elementary steps [2,3] and (iii) the SOC geometry with the gas flow configuration [4,5]. This multiscale model has been developed considering a typical cell composed of a dense electrolyte in Y 0.148 Zr 0.852 O 1.926 (8YSZ) sandwiched between an O 2 electrode in La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3- d -Ce 0.8 Gd 0.2 O 2-δ (LSCF-GDC) and an H 2 electrode made of Ni and YSZ (Ni-YSZ). The model has been validated using a specific experimental setup which was developed to measure the local polarization curves along the cell length. For this purpose, a specific design of the interconnect has been proposed in order to probe the local current density on the standard studied cells (Fig. 1a) [6]. It has been found that the model is able to reproduce accurately the global and local polarizations curves in SOFC and SOEC modes (Fig. 1a and 1b). The stationary model has been also extended to compute electrochemical impedance spectra by keeping the full description of the reaction mechanisms in elementary steps. This dynamic model, which is able to compute the impedance diagrams at Open Circuit Voltage (OCV) and under polarization, has been compared to the experimental data. As shown in Fig. 1c and 1d, a reasonable agreement has been found between the measurements and the simulations without any fitting. The validated stationary and dynamic model has been used to analyze the cell operation in electrolysis and fuel cell modes. The activated reaction pathways associated with the elementary steps in the active layers have been investigated depending on the position along the cell length. The different contributions arising in the impedance spectra have been also identified and discussed. References [1]","PeriodicalId":11461,"journal":{"name":"ECS Meeting Abstracts","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135089133","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-28DOI: 10.1149/ma2023-01442384mtgabs
Lalith Krishna Samanth Bonagiri, Kaustubh S. Panse, Shan Zhou, Haiyi Wu, Narayana R. Aluru, Yingjie Zhang
Charge distributions at electrode-electrolyte interfaces play a crucial role in many electrochemical processes, some of which are electrocatalysis, supercapacitors, batteries etc., However, most experimental techniques, either microscopy or spectroscopy tools that are used to probe these systems, cannot provide any information about the interfacial spatial charge distribution. Techniques based on kelvin-probe force microscopy (KPFM) can provide some information, however they have a very limited depth of resolution and can only work with extremely dilute electrolytes. Recently, we developed a technique known as charge profiling three-dimensional (3D) atomic force microscopy (CP-3D-AFM) which could map out the charge densities at angstrom-depth resolution. The method is based on measuring 3D-AFM maps at different electrode potentials and further using electrostatic calculations to obtain the charge density depth profiles at the respective potentials. We used this method to measure charge distributions in highly ionic electrolyte systems and can explain their differential capacitance profiles. This CP-3D-AFM technique could enable to obtain molecular structural insights for a wide range of electrolyte systems and serve in designing principles for engineering effective electrode-electrolyte interfaces.
{"title":"Unraveling Spatial Charge Density Distributions at Electrode-Electrolyte Interfaces","authors":"Lalith Krishna Samanth Bonagiri, Kaustubh S. Panse, Shan Zhou, Haiyi Wu, Narayana R. Aluru, Yingjie Zhang","doi":"10.1149/ma2023-01442384mtgabs","DOIUrl":"https://doi.org/10.1149/ma2023-01442384mtgabs","url":null,"abstract":"Charge distributions at electrode-electrolyte interfaces play a crucial role in many electrochemical processes, some of which are electrocatalysis, supercapacitors, batteries etc., However, most experimental techniques, either microscopy or spectroscopy tools that are used to probe these systems, cannot provide any information about the interfacial spatial charge distribution. Techniques based on kelvin-probe force microscopy (KPFM) can provide some information, however they have a very limited depth of resolution and can only work with extremely dilute electrolytes. Recently, we developed a technique known as charge profiling three-dimensional (3D) atomic force microscopy (CP-3D-AFM) which could map out the charge densities at angstrom-depth resolution. The method is based on measuring 3D-AFM maps at different electrode potentials and further using electrostatic calculations to obtain the charge density depth profiles at the respective potentials. We used this method to measure charge distributions in highly ionic electrolyte systems and can explain their differential capacitance profiles. This CP-3D-AFM technique could enable to obtain molecular structural insights for a wide range of electrolyte systems and serve in designing principles for engineering effective electrode-electrolyte interfaces.","PeriodicalId":11461,"journal":{"name":"ECS Meeting Abstracts","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135089142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-28DOI: 10.1149/ma2023-01452465mtgabs
Linda Bolay, Eiji Hosono, Yoshitsugu Sone, Arnulf Latz, Birger Horstmann
In-orbit satellite REIMEI, developed by the Japan Aerospace Exploration Agency (JAXA), has been relying on off-the-shelf Li-ion batteries since its launch in 2005 [1]. The performance and durability of Li-ion batteries is impacted by various degradation mechanisms, one of which is the growth of the solid-electrolyte interphase (SEI). Long-term SEI growth is the greatest contributor to capacity fade in lithium-ion batteries. In this contribution, we will address several aspects of the modeling and simulation of the batteries of satellite REIMEI. We simulate long-term degradation under the generic LEO satellite cycling conditions in a P2D framework. The simulations are validated with experiments and in-flight data provided by JAXA [1]. Our group has developed models for long-term SEI growth [2,3]. To show the inhomogeneous growth of the SEI in 3D, we perform microstructure-resolved simulations [4]. These studies are the foundation for analyzing the states of the batteries, which cannot be measured in operando. To estimate the state of charge and state of health, we make use of filter techniques and the in-flight data of the satellite batteries. Kalman filters are particularly suitable for the noisy data. Since the states change on different timescales, a multi-time-scale algorithm is applied, where two filters are combined. With this approach, we aim to reliably predict the lifetime of satellite batteries in orbit. References [1] M. Uno, et al. , J. Power Sources , 196(20) (2011) 8755–8763. [2] F. Single, et al. , ChemSusChem , 11(12) (2018) 1950–1955. [3] L. von Kolzenberg, et al. , ChemSusChem , 13(15) (2020) 3901–3910. [4] L. Bolay, et al. , J. Power Sources Advances , 14 (2022) 100083.
{"title":"Degradation and Multi-Time-Scale State Estimation of Li-Ion Batteries in Satellites","authors":"Linda Bolay, Eiji Hosono, Yoshitsugu Sone, Arnulf Latz, Birger Horstmann","doi":"10.1149/ma2023-01452465mtgabs","DOIUrl":"https://doi.org/10.1149/ma2023-01452465mtgabs","url":null,"abstract":"In-orbit satellite REIMEI, developed by the Japan Aerospace Exploration Agency (JAXA), has been relying on off-the-shelf Li-ion batteries since its launch in 2005 [1]. The performance and durability of Li-ion batteries is impacted by various degradation mechanisms, one of which is the growth of the solid-electrolyte interphase (SEI). Long-term SEI growth is the greatest contributor to capacity fade in lithium-ion batteries. In this contribution, we will address several aspects of the modeling and simulation of the batteries of satellite REIMEI. We simulate long-term degradation under the generic LEO satellite cycling conditions in a P2D framework. The simulations are validated with experiments and in-flight data provided by JAXA [1]. Our group has developed models for long-term SEI growth [2,3]. To show the inhomogeneous growth of the SEI in 3D, we perform microstructure-resolved simulations [4]. These studies are the foundation for analyzing the states of the batteries, which cannot be measured in operando. To estimate the state of charge and state of health, we make use of filter techniques and the in-flight data of the satellite batteries. Kalman filters are particularly suitable for the noisy data. Since the states change on different timescales, a multi-time-scale algorithm is applied, where two filters are combined. With this approach, we aim to reliably predict the lifetime of satellite batteries in orbit. References [1] M. Uno, et al. , J. Power Sources , 196(20) (2011) 8755–8763. [2] F. Single, et al. , ChemSusChem , 11(12) (2018) 1950–1955. [3] L. von Kolzenberg, et al. , ChemSusChem , 13(15) (2020) 3901–3910. [4] L. Bolay, et al. , J. Power Sources Advances , 14 (2022) 100083.","PeriodicalId":11461,"journal":{"name":"ECS Meeting Abstracts","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135089144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-28DOI: 10.1149/ma2023-01462505mtgabs
Stephen B. Cronin
We report various aspects of electrochemistry and photoelectrochemistry using in situ spectroscopy of electrode (metal) and photoelectrode (semiconductor) interfaces in situ under electrochemical working conditions. These spectroscopies include sum frequency generation (SFG), transient reflectance/absorption spectroscopy (TAS/TRS), and surface enhanced Raman spectroscopy (SERS). Using surface enhanced Raman scattering (SERS) spectroscopy, we monitor local electric fields using Stark-shifts of nitrile-functionalized silicon photoelectrodes. 6 Using Graphene-enhanced Raman spectroscopy (GERS)-based Stark-shifts, we measure local electric fields and local charge densities at monolayer graphene electrode surfaces. 1 We also measured the stacking dependence and Resonant interlayer excitation of monolayer WSe 2 /MoSe 2 heterostructures for photocatalytic energy conversion. 2 Using sum frequency generation (SFG) spectroscopy, we measure the voltage dependence of the orientation of D 2 O molecules at a graphene electrode surface, which is related back to the “stiffness of the ensemble”. 3 In particular, we measured the “free OD” feature in the spectra, which corresponds to the topmost water molecule that is rotated up out of the bulk water solution and is, therefore, not hydrogen bonded. Using transient absorption spectroscopy (TAS), we measure the lifetime of hot electrons photoexcited in plasmon resonant nanostructures. 5 Using transient reflectance spectroscopy (TRS), we measure the photoexcited carrier dynamics in a GaP/TiO 2 photoelectrode, as well as the electrostatic field dynamics at this semiconductor-liquid interfaces in situ under various electrochemical potentials. 4 Here, the electrostatic fields at the surface of the semiconductor are measured via Franz−Keldysh oscillations (FKO). These spectra reveal that the nanoscale TiO 2 protection layer enhances the built-in field and charge separation performance of GaP photoelectrodes. Shi, H.T., B.F. Zhao, J. Ma, M.J. Bronson, Z. Cai, J.H. Chen, Y. Wang, M. Cronin, L. Jensen and S.B. Cronin, Measuring Local Electric Fields and Local Charge Densities at Electrode Surfaces Using Graphene-Enhanced Raman Spectroscopy (GERS)-Based Stark-Shifts. ACS Applied Materials & Interfaces, 11 , 36252-36258 (2019). Chen, J., C.S. Bailey, D. Cui, Y. Wang, B. Wang, H. Shi, Z. Cai, E. Pop, C. Zhou and S.B. Cronin, Stacking Independence and Resonant Interlayer Excitation of Monolayer WSe2/MoSe2 Heterostructures for Photocatalytic Energy Conversion. ACS Applied Nano Materials, DOI:10.1021/acsanm.9b01898 (2020). Montenegro, A., C. Dutta, M. Mammetkuliev, H.T. Shi, B.Y. Hou, D. Bhattacharyya, B.F. Zhao, S.B. Cronin and A.V. Benderskii, Asymmetric response of interfacial water to applied electric fields. Nature, 594 , 62 (2021). Xu, Z.H., B.Y. Hou, F.Y. Zhao, Z. Cai, H.T. Shi, Y.W. Liu, C.L. Hill, D.G. Musaev, M. Mecklenburg, S.B. Cronin and T.Q. Lian, Nanoscale TiO 2 Protection Layer Enhances the Built-In Field and C
我们在电化学工作条件下使用电极(金属)和光电极(半导体)界面的原位光谱报告电化学和光电化学的各个方面。这些光谱包括和频产生(SFG)、瞬态反射/吸收光谱(TAS/TRS)和表面增强拉曼光谱(SERS)。利用表面增强拉曼散射(SERS)光谱,我们利用硝基功能化硅光电极的斯塔克位移监测局部电场。利用基于石墨烯增强拉曼光谱(GERS)的斯塔克位移,我们测量了单层石墨烯电极表面的局部电场和局部电荷密度。我们还测量了单层WSe 2 /MoSe 2异质结构对光催化能量转换的堆叠依赖性和共振层间激发。利用和频产生(SFG)光谱,我们测量了石墨烯电极表面d2o分子取向的电压依赖性,这与“系综刚度”有关。特别是,我们测量了光谱中的“自由OD”特征,它对应于最上面的水分子,它从散装水溶液中旋转出来,因此没有氢键。利用瞬态吸收光谱(TAS)测量了等离子体共振纳米结构中光激发热电子的寿命。利用瞬态反射光谱(TRS),我们测量了GaP/ tio2光电极中的光激发载流子动力学,以及在不同电化学电位下半导体-液体界面处的静电场动力学。在这里,半导体表面的静电场是通过Franz - Keldysh振荡(FKO)来测量的。这些光谱表明,纳米tio2保护层增强了GaP光电极的内置场和电荷分离性能。施洪涛,赵宝峰,马建军,蔡志强,陈建辉,王勇,M. Cronin, L. Jensen, S.B. Cronin,基于石墨烯增强拉曼光谱(GERS)的电极表面局部电场和局部电荷密度测量。ACS应用材料公司通信学报,11,36252-36258(2019)。C.S.贝利,陈,J·d·崔,y, b . Wang h·史,z Cai, e .流行c .周和S.B.克罗宁,叠加独立和共振层间激发的单层WSe2 / MoSe2异质结构光催化能量转换。ACS应用纳米材料,DOI:10.1021/acsanm。9 b01898(2020)。A. Montenegro, A. C. Dutta, M. Mammetkuliev, Shi h.t t, Hou B.Y., D. Bhattacharyya, B.F. Zhao, S.B. Cronin, A. v . Benderskii,界面水对外加电场的不对称响应。自然,594,62(2021)。徐志辉,侯炳银,赵芳艳,蔡志强,石洪涛,刘永文,刘春林,D.G. Musaev, M. Mecklenburg, S.B. Cronin, Lian T.Q.,纳米tio2保护层对GaP光电极内嵌场和电荷分离性能的影响。纳米快报,21,8017-8024(2021)。王宇,王毅,Indu Aravind,蔡智,沈朗,张伯新,王博,陈继涵,赵伯凡,石浩天,Jahan M. Dawlaty, Stephen B. Cronin。等离子体共振光栅结构中热电子驱动光催化的超快动力学原位研究。美国化学学会杂志。DOI: 10.1021 /江淮。1 c12069(2022)。史浩天,Ryan T. Pekarek,陈然,张伯欣,王宇,Indu Aravind,蔡智,Lasse Jensen, Nathan R. Neale, Stephen B. Cronin。在萘基腈功能化硅光电极上使用Stark位移监测局部电场。物理化学学报,29(4),17000-17005(2020)。
{"title":"(Invited) In Situ Spectroscopy of Electrocatalytic and Photocatalytic Interfaces","authors":"Stephen B. Cronin","doi":"10.1149/ma2023-01462505mtgabs","DOIUrl":"https://doi.org/10.1149/ma2023-01462505mtgabs","url":null,"abstract":"We report various aspects of electrochemistry and photoelectrochemistry using in situ spectroscopy of electrode (metal) and photoelectrode (semiconductor) interfaces in situ under electrochemical working conditions. These spectroscopies include sum frequency generation (SFG), transient reflectance/absorption spectroscopy (TAS/TRS), and surface enhanced Raman spectroscopy (SERS). Using surface enhanced Raman scattering (SERS) spectroscopy, we monitor local electric fields using Stark-shifts of nitrile-functionalized silicon photoelectrodes. 6 Using Graphene-enhanced Raman spectroscopy (GERS)-based Stark-shifts, we measure local electric fields and local charge densities at monolayer graphene electrode surfaces. 1 We also measured the stacking dependence and Resonant interlayer excitation of monolayer WSe 2 /MoSe 2 heterostructures for photocatalytic energy conversion. 2 Using sum frequency generation (SFG) spectroscopy, we measure the voltage dependence of the orientation of D 2 O molecules at a graphene electrode surface, which is related back to the “stiffness of the ensemble”. 3 In particular, we measured the “free OD” feature in the spectra, which corresponds to the topmost water molecule that is rotated up out of the bulk water solution and is, therefore, not hydrogen bonded. Using transient absorption spectroscopy (TAS), we measure the lifetime of hot electrons photoexcited in plasmon resonant nanostructures. 5 Using transient reflectance spectroscopy (TRS), we measure the photoexcited carrier dynamics in a GaP/TiO 2 photoelectrode, as well as the electrostatic field dynamics at this semiconductor-liquid interfaces in situ under various electrochemical potentials. 4 Here, the electrostatic fields at the surface of the semiconductor are measured via Franz−Keldysh oscillations (FKO). These spectra reveal that the nanoscale TiO 2 protection layer enhances the built-in field and charge separation performance of GaP photoelectrodes. Shi, H.T., B.F. Zhao, J. Ma, M.J. Bronson, Z. Cai, J.H. Chen, Y. Wang, M. Cronin, L. Jensen and S.B. Cronin, Measuring Local Electric Fields and Local Charge Densities at Electrode Surfaces Using Graphene-Enhanced Raman Spectroscopy (GERS)-Based Stark-Shifts. ACS Applied Materials & Interfaces, 11 , 36252-36258 (2019). Chen, J., C.S. Bailey, D. Cui, Y. Wang, B. Wang, H. Shi, Z. Cai, E. Pop, C. Zhou and S.B. Cronin, Stacking Independence and Resonant Interlayer Excitation of Monolayer WSe2/MoSe2 Heterostructures for Photocatalytic Energy Conversion. ACS Applied Nano Materials, DOI:10.1021/acsanm.9b01898 (2020). Montenegro, A., C. Dutta, M. Mammetkuliev, H.T. Shi, B.Y. Hou, D. Bhattacharyya, B.F. Zhao, S.B. Cronin and A.V. Benderskii, Asymmetric response of interfacial water to applied electric fields. Nature, 594 , 62 (2021). Xu, Z.H., B.Y. Hou, F.Y. Zhao, Z. Cai, H.T. Shi, Y.W. Liu, C.L. Hill, D.G. Musaev, M. Mecklenburg, S.B. Cronin and T.Q. Lian, Nanoscale TiO 2 Protection Layer Enhances the Built-In Field and C","PeriodicalId":11461,"journal":{"name":"ECS Meeting Abstracts","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135089152","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}