Pub Date : 2024-09-04DOI: 10.1149/1945-7111/ad6e1d
Divya Deep Yadav, Ajay Kumar, Ranjana Jha, Sukhvir Singh
In the present work, a simple and effective hydrothermal method has been used to synthesize a nanocomposite of nickel oxide and molybdenum disulphide. Structural and optical characterizations of the as-synthesised MoS2/NiO nanocomposite nanoparticles were carried out using X-ray diffraction (XRD) and UV-visible spectroscopy techniques. The major peaks of MoS2 and NiO were detected in XRD, confirming the formation of a composite. The reduced band gap of 2.84 eV of MoS2/NiO nanocomposite, as compared to pure NiO with a 3.1 eV bandgap, indicates a blue shift. The surface morphology of MoS2/NiO nanocomposite was measured using field-emission scanning electron microscopy, showing a sheet-like structure with fine particles overlaid on them. Cyclic voltammetry and electrochemical impedance spectroscopy (EIS) were used to determine the processes of charge transfer between electrodes, diffusion of molecules and ions within the electrolyte solution, and ion adsorption on the surface of the the electrode. The as-prepared composite shows an enhanced specific capacitance of 246 F g−1 at20 mV sec−1, a scan rate of which was more than both base materials in pristine form. EIS results thus obtained may give a new direction for supercapacitor applications with the as-synthesized sample.
本研究采用简单有效的水热法合成了氧化镍和二硫化钼的纳米复合材料。利用 X 射线衍射 (XRD) 和紫外可见光谱技术对合成的 MoS2/NiO 纳米复合纳米粒子进行了结构和光学表征。在 XRD 中检测到了 MoS2 和 NiO 的主要峰值，证实了复合材料的形成。与带隙为 3.1 eV 的纯 NiO 相比，MoS2/NiO 纳米复合材料的带隙减小到 2.84 eV，表明发生了蓝移。使用场发射扫描电子显微镜测量了 MoS2/NiO 纳米复合材料的表面形貌，结果表明其呈片状结构，上面叠加有细小颗粒。循环伏安法和电化学阻抗谱（EIS）用于确定电极间的电荷转移、电解质溶液中分子和离子的扩散以及电极表面的离子吸附过程。制备的复合材料在 20 mV sec-1 时的比电容为 246 F g-1，扫描速率高于两种原始形式的基底材料。由此获得的 EIS 结果可能会为合成样品的超级电容器应用提供一个新的方向。
{"title":"Flexible Ni-Foam-Based Electrode with Novel MoS2/NiO Nanocomposite for Superior Supercapacitor Applications","authors":"Divya Deep Yadav, Ajay Kumar, Ranjana Jha, Sukhvir Singh","doi":"10.1149/1945-7111/ad6e1d","DOIUrl":"https://doi.org/10.1149/1945-7111/ad6e1d","url":null,"abstract":"In the present work, a simple and effective hydrothermal method has been used to synthesize a nanocomposite of nickel oxide and molybdenum disulphide. Structural and optical characterizations of the as-synthesised MoS<sub>2</sub>/NiO nanocomposite nanoparticles were carried out using X-ray diffraction (XRD) and UV-visible spectroscopy techniques. The major peaks of MoS<sub>2</sub> and NiO were detected in XRD, confirming the formation of a composite. The reduced band gap of 2.84 eV of MoS2/NiO nanocomposite, as compared to pure NiO with a 3.1 eV bandgap, indicates a blue shift. The surface morphology of MoS2/NiO nanocomposite was measured using field-emission scanning electron microscopy, showing a sheet-like structure with fine particles overlaid on them. Cyclic voltammetry and electrochemical impedance spectroscopy (EIS) were used to determine the processes of charge transfer between electrodes, diffusion of molecules and ions within the electrolyte solution, and ion adsorption on the surface of the the electrode. The as-prepared composite shows an enhanced specific capacitance of 246 F g−1 at20 mV sec−1, a scan rate of which was more than both base materials in pristine form. EIS results thus obtained may give a new direction for supercapacitor applications with the as-synthesized sample.","PeriodicalId":17364,"journal":{"name":"Journal of The Electrochemical Society","volume":"3 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-04DOI: 10.1149/1945-7111/ad71f9
Shunsuke Tomita, Tatsuya Kikuchi
The electropolishing behavior of pure magnesium and its alloys in ethylene glycol (EG), diethylene glycol (DEG), triethylene glycol (TrEG), and tetraethylene glycol (TeEG) solutions containing sodium chloride was investigated using electrochemical measurements, microscopic observations, and reflectance measurements. Large light-grayish cloudy areas with micrometer-scale linear irregularities were formed on the magnesium surface via constant-voltage electrolysis in the EG solution, whereas mirror-finished magnesium surfaces were successfully obtained in the DEG and TeEG solutions. Among these, the DEG solution is considered appropriate for electropolishing because of its lower viscosity and market price. The reflectance of the entire visible wavelength region gradually increased with time during electrolysis in the DEG solution at 308 K. We found that short-term electrolysis for 3 min at the higher voltage of 75 V should be selected if a moderately polished surface is to be rapidly obtained, whereas long-term electrolysis for 60–300 min at 50 V should be performed if a highly polished surface with an extremely high reflectivity measuring more than 80% can be obtained. Three-dimensional magnesium specimens with curved and spiral shapes and an LZ91 magnesium alloy consisting of a simple solid-solution matrix can also be electropolished via electrolysis in a DEG solution.
通过电化学测量、显微镜观察和反射率测量，研究了纯镁及其合金在含氯化钠的乙二醇（EG）、二甘醇（DEG）、三甘醇（TrEG）和四甘醇（TeEG）溶液中的电解抛光行为。在 EG 溶液中通过恒压电解，镁表面形成了大面积浅灰色浑浊区，并伴有微米级的线性不规则，而在 DEG 和 TeEG 溶液中则成功获得了镜面镁表面。其中，DEG 溶液因其较低的粘度和市场价格而被认为适合电解抛光。在 308 K 的 DEG 溶液中进行电解时，整个可见光波长区域的反射率随着时间的推移逐渐增加。我们发现，如果要快速获得中等抛光的表面，应选择在 75 V 的较高电压下进行 3 分钟的短期电解，而如果要获得反射率超过 80% 的高抛光表面，则应在 50 V 的电压下进行 60-300 分钟的长期电解。具有弯曲和螺旋形状的三维镁试样以及由简单固溶体基质组成的 LZ91 镁合金也可以通过在 DEG 溶液中电解进行电抛光。
{"title":"Electropolishing of Magnesium and Its Alloys Using a Safe Glycol Solution Containing Sodium Chloride","authors":"Shunsuke Tomita, Tatsuya Kikuchi","doi":"10.1149/1945-7111/ad71f9","DOIUrl":"https://doi.org/10.1149/1945-7111/ad71f9","url":null,"abstract":"The electropolishing behavior of pure magnesium and its alloys in ethylene glycol (EG), diethylene glycol (DEG), triethylene glycol (TrEG), and tetraethylene glycol (TeEG) solutions containing sodium chloride was investigated using electrochemical measurements, microscopic observations, and reflectance measurements. Large light-grayish cloudy areas with micrometer-scale linear irregularities were formed on the magnesium surface via constant-voltage electrolysis in the EG solution, whereas mirror-finished magnesium surfaces were successfully obtained in the DEG and TeEG solutions. Among these, the DEG solution is considered appropriate for electropolishing because of its lower viscosity and market price. The reflectance of the entire visible wavelength region gradually increased with time during electrolysis in the DEG solution at 308 K. We found that short-term electrolysis for 3 min at the higher voltage of 75 V should be selected if a moderately polished surface is to be rapidly obtained, whereas long-term electrolysis for 60–300 min at 50 V should be performed if a highly polished surface with an extremely high reflectivity measuring more than 80% can be obtained. Three-dimensional magnesium specimens with curved and spiral shapes and an LZ91 magnesium alloy consisting of a simple solid-solution matrix can also be electropolished via electrolysis in a DEG solution.","PeriodicalId":17364,"journal":{"name":"Journal of The Electrochemical Society","volume":"26 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-04DOI: 10.1149/1945-7111/ad7291
Xinsheng Wu, Jay F. Whitacre
P2-phased layered oxide materials have been extensively studied as cathode material for sodium-ion batteries due to their high capacities and ionic conductivities, making them promising for large-scale applications. Additionally, manganese-based compounds, with their low cost and high capacity, have attracted significant attention in recent years. However, challenges remain regarding durability issues and related structural instability caused by the Jahn-Teller effect induced by Mn3+ ions formed during the cycling process in these materials, which causes manganese dissolution during use. In this study, we introduce a cathode composition of Na0.8Mn0.75Fe0.2Al0.05O2 and show that bismuth doping enhances the structural stability of the cathode material during electrochemical cycling. Electrodes with varying levels of bismuth doping were compared in half-cell configurations; material with 1% bismuth doping demonstrated outstanding stability, retaining 95.8% capacity after 200 cycles at a 0.2 C rate through the full potential range. dQ/dV analysis shows that bismuth doping effectively suppresses the excess Mn redox, which could otherwise deteriorate the cathode structure. As a proof of concept, Bi-doped materials were implemented in full cells paired with hard carbon that exhibited much better stability than those without bismuth doping. Lastly, the moisture and air stability of the bismuth-doped electrode were tested, demonstrating good stability.
{"title":"Bi-Doped P2 layered Sodium-Ion Battery Cathode with Improved Cycling Stability","authors":"Xinsheng Wu, Jay F. Whitacre","doi":"10.1149/1945-7111/ad7291","DOIUrl":"https://doi.org/10.1149/1945-7111/ad7291","url":null,"abstract":"P2-phased layered oxide materials have been extensively studied as cathode material for sodium-ion batteries due to their high capacities and ionic conductivities, making them promising for large-scale applications. Additionally, manganese-based compounds, with their low cost and high capacity, have attracted significant attention in recent years. However, challenges remain regarding durability issues and related structural instability caused by the Jahn-Teller effect induced by Mn<sup>3+</sup> ions formed during the cycling process in these materials, which causes manganese dissolution during use. In this study, we introduce a cathode composition of Na<sub>0.8</sub>Mn<sub>0.75</sub>Fe<sub>0.2</sub>Al<sub>0.05</sub>O<sub>2</sub> and show that bismuth doping enhances the structural stability of the cathode material during electrochemical cycling. Electrodes with varying levels of bismuth doping were compared in half-cell configurations; material with 1% bismuth doping demonstrated outstanding stability, retaining 95.8% capacity after 200 cycles at a 0.2 C rate through the full potential range. dQ/dV analysis shows that bismuth doping effectively suppresses the excess Mn redox, which could otherwise deteriorate the cathode structure. As a proof of concept, Bi-doped materials were implemented in full cells paired with hard carbon that exhibited much better stability than those without bismuth doping. Lastly, the moisture and air stability of the bismuth-doped electrode were tested, demonstrating good stability.","PeriodicalId":17364,"journal":{"name":"Journal of The Electrochemical Society","volume":"9 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-04DOI: 10.1149/1945-7111/ad7297
Sheng S. Zhang
Reducing particle size has been widely adopted to mitigate the cracking and pulverization of silicon particles and to enhance electrode reaction kinetics for silicon electrodes in cycling. However, the increased surface area promotes parasitic reactions with electrolyte solvents. This work comparatively studies nano-sized silicon (Si-NP) and micro-sized silicon (Si-MP) as anodes in Li-ion cells using nickel-rich LiNi0.80Co0.1Mn0.1O2 (NCM811) as the cathode. The focus is on capacity, capacity retention, Coulombic efficiency (CE), and rate capability by changing the negative-to-positive capacity (N/P) ratio and charging cutoff voltage. It is found that Si-NP initially exhibits a CE above 90%, however, it rarely exceeds 98% in subsequent cycles, leading to rapid capacity fade. Additionally, increasing the N/P ratio and lowering the charging cutoff voltage does not obviously improve the cycling stability of Si-NP cells. Compared with Si-NP, Si-MP experiences lower capacity and lower CE in the initial several cycles. However, with continued cycling, both the capacity and CE gradually increase to a maximum and stably remain at ∼99.9%. The findings of this work suggest that, with its excellent rate capability, Si-MP may be more advantageous than Si-NP in developing practical Li-ion batteries, provided its low CE during initial cycles can be successfully addressed.
减小硅颗粒的尺寸已被广泛采用，以减轻硅颗粒的开裂和粉碎，并增强硅电极在循环过程中的电极反应动力学。然而，表面积的增加会促进与电解质溶剂的寄生反应。本研究比较性地研究了纳米级硅（Si-NP）和微米级硅（Si-MP）在锂离子电池中用作阳极的情况，阴极使用富镍 LiNi0.80Co0.1Mn0.1O2 (NCM811)。研究重点是通过改变负负容量比（N/P）和充电截止电压来研究容量、容量保持率、库仑效率（CE）和速率能力。研究发现，Si-NP 最初的 CE 超过 90%，但在随后的循环中很少超过 98%，从而导致容量快速衰减。此外，提高 N/P 比和降低充电截止电压并不能明显改善 Si-NP 电池的循环稳定性。与 Si-NP 相比，Si-MP 在最初的几个循环中容量较低，CE 也较低。然而，随着循环的持续进行，容量和 CE 都会逐渐增加到最大值，并稳定地保持在 ∼ 99.9%。这项工作的研究结果表明，Si-MP 具有优异的速率能力，在开发实用锂离子电池方面可能比 Si-NP 更具优势，但前提是能成功解决其在初始循环期间的低 CE 问题。
{"title":"A Comparative Study of Nano and Micro-Sized Silicon in Lithium-Ion Cells with a Nickel-Rich Cathode","authors":"Sheng S. Zhang","doi":"10.1149/1945-7111/ad7297","DOIUrl":"https://doi.org/10.1149/1945-7111/ad7297","url":null,"abstract":"Reducing particle size has been widely adopted to mitigate the cracking and pulverization of silicon particles and to enhance electrode reaction kinetics for silicon electrodes in cycling. However, the increased surface area promotes parasitic reactions with electrolyte solvents. This work comparatively studies nano-sized silicon (Si-NP) and micro-sized silicon (Si-MP) as anodes in Li-ion cells using nickel-rich LiNi<sub>0.80</sub>Co<sub>0.1</sub>Mn<sub>0.1</sub>O<sub>2</sub> (NCM811) as the cathode. The focus is on capacity, capacity retention, Coulombic efficiency (CE), and rate capability by changing the negative-to-positive capacity (N/P) ratio and charging cutoff voltage. It is found that Si-NP initially exhibits a CE above 90%, however, it rarely exceeds 98% in subsequent cycles, leading to rapid capacity fade. Additionally, increasing the N/P ratio and lowering the charging cutoff voltage does not obviously improve the cycling stability of Si-NP cells. Compared with Si-NP, Si-MP experiences lower capacity and lower CE in the initial several cycles. However, with continued cycling, both the capacity and CE gradually increase to a maximum and stably remain at ∼99.9%. The findings of this work suggest that, with its excellent rate capability, Si-MP may be more advantageous than Si-NP in developing practical Li-ion batteries, provided its low CE during initial cycles can be successfully addressed.","PeriodicalId":17364,"journal":{"name":"Journal of The Electrochemical Society","volume":"32 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The burgeoning intersection of machine learning (ML) with electrochemical sensing heralds a transformative era in analytical science, pushing the boundaries of what’s possible in detecting and quantifying chemical substances with unprecedented precision and efficiency. This convergence has accelerated a number of discoveries, improving electrochemical sensors’ sensitivity, selectivity, and ability to comprehend complicated data streams in real-time. Such advancements are crucial across various applications, from monitoring health biomarkers to detecting environmental pollutants and ensuring industrial safety. Yet, this integration is not without its challenges; it necessitates navigating intricate ethical considerations around data use, ensuring robust data privacy measures, and developing specialized software tools that balance accessibility and security. As the field progresses, addressing these challenges head-on is essential for harnessing the full potential of ML-enhanced electrochemical sensing. This review briefly explores these dimensions, spotlighting the significant technological strides, the ethical landscape, and the dynamic interplay between open-source and proprietary software solutions while also casting a forward gaze at the promising future directions of this interdisciplinary venture.
机器学习（ML）与电化学传感的蓬勃发展预示着分析科学进入了一个变革性的时代，以前所未有的精度和效率推动了化学物质检测和量化的发展。这种融合加速了一系列发现，提高了电化学传感器的灵敏度、选择性和实时理解复杂数据流的能力。从监测健康生物标志物到检测环境污染物和确保工业安全，这些进步在各种应用中都至关重要。然而，这种整合并非没有挑战；它需要驾驭数据使用方面错综复杂的道德考量，确保强有力的数据隐私措施，以及开发兼顾可访问性和安全性的专业软件工具。随着该领域的不断进步，正面应对这些挑战对于充分发挥 ML 增强电化学传感的潜力至关重要。本综述简要探讨了这些方面的问题，重点介绍了重大的技术进步、伦理状况以及开源和专有软件解决方案之间的动态相互作用，同时还展望了这一跨学科事业充满希望的未来发展方向。
{"title":"Review—Machine Learning-Driven Advances in Electrochemical Sensing: A Horizon Scan","authors":"Kaviya Murugan, Karnan Gopalakrishnan, Kogularasu Sakthivel, Sakthinathan Subramanian, I-Cheng Li, Yen-Yi Lee, Te-Wei Chiu, Guo-Ping Chang-Chien","doi":"10.1149/1945-7111/ad6b4a","DOIUrl":"https://doi.org/10.1149/1945-7111/ad6b4a","url":null,"abstract":"The burgeoning intersection of machine learning (ML) with electrochemical sensing heralds a transformative era in analytical science, pushing the boundaries of what’s possible in detecting and quantifying chemical substances with unprecedented precision and efficiency. This convergence has accelerated a number of discoveries, improving electrochemical sensors’ sensitivity, selectivity, and ability to comprehend complicated data streams in real-time. Such advancements are crucial across various applications, from monitoring health biomarkers to detecting environmental pollutants and ensuring industrial safety. Yet, this integration is not without its challenges; it necessitates navigating intricate ethical considerations around data use, ensuring robust data privacy measures, and developing specialized software tools that balance accessibility and security. As the field progresses, addressing these challenges head-on is essential for harnessing the full potential of ML-enhanced electrochemical sensing. This review briefly explores these dimensions, spotlighting the significant technological strides, the ethical landscape, and the dynamic interplay between open-source and proprietary software solutions while also casting a forward gaze at the promising future directions of this interdisciplinary venture.<inline-formula>\u0000<inline-graphic xlink:href=\"jesad6b4a-ga.jpg\" xlink:type=\"simple\"></inline-graphic>\u0000</inline-formula>","PeriodicalId":17364,"journal":{"name":"Journal of The Electrochemical Society","volume":"16 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-03DOI: 10.1149/1945-7111/ad728d
Fareeha Marriam, Aleena Arshad, Khadija Munawar, Muhammad Adil Mansoor, Mehdi Ebadi, Rabia Naeem
The superior kinetics of charge carriers and greater visible light absorption are important factors for enhancing photoelectrochemical performance. Herein, the core–shell heterostructure has been developed by encapsulating single-phase MnZnO3 over TiO2 nanotubes by aerosol-assisted chemical vapor deposition approach. The fabricated photoanodes have been characterized by employing various techniques including X-ray diffraction, Raman spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, atomic force microscopy, and photoluminescence. Moreover, the mechanism for electron/hole transfer has been focused by a brief electrochemical investigation. The bilayer 1D/2D TiO2@MnZnO3 photoanode exhibited higher current density (2 mA cm−2) as compared to pristine TiO2-nanotubes (0.174 mA cm−2) at 1.52 V vs RHE. The superior photoactivity of heterostructure is attributed to the rapid transfer of photogenerated charge carriers via the Type-II mechanism. Furthermore, the reduced band gap (2.05 eV) accounts for good absorption in the visible region of light, while the interfacial electric field allowed the improved charge separation. The synergistic strategy in the present work demonstrates the promising significance of a heterojunction interface to optimize photovoltaic devices.
卓越的电荷载流子动力学和更强的可见光吸收能力是提高光电化学性能的重要因素。本文通过气溶胶辅助化学气相沉积方法，在 TiO2 纳米管上封装单相 MnZnO3，从而开发出核壳异质结构。利用 X 射线衍射、拉曼光谱、扫描电子显微镜、能量色散 X 射线光谱、原子力显微镜和光致发光等多种技术对制备的光阳极进行了表征。此外，还通过简短的电化学研究关注了电子/空穴传输机制。与原始 TiO2 纳米管（0.174 mA cm-2）相比，双层 1D/2D TiO2@MnZnO3 光阳极在 1.52 V 对比 RHE 时表现出更高的电流密度（2 mA cm-2）。异质结构优异的光活性归因于光生电荷载流子通过 II 型机制的快速转移。此外，降低的带隙（2.05 eV）使其在可见光区域具有良好的吸收性，而界面电场则改善了电荷分离。本研究中的协同策略表明，异质结界面对优化光伏设备具有重要意义。
{"title":"Synergistic Approach of TiO2@MnZnO3 Heterostructure for Efficient Photoelectrochemical Water Splitting","authors":"Fareeha Marriam, Aleena Arshad, Khadija Munawar, Muhammad Adil Mansoor, Mehdi Ebadi, Rabia Naeem","doi":"10.1149/1945-7111/ad728d","DOIUrl":"https://doi.org/10.1149/1945-7111/ad728d","url":null,"abstract":"The superior kinetics of charge carriers and greater visible light absorption are important factors for enhancing photoelectrochemical performance. Herein, the core–shell heterostructure has been developed by encapsulating single-phase MnZnO<sub>3</sub> over TiO<sub>2</sub> nanotubes by aerosol-assisted chemical vapor deposition approach. The fabricated photoanodes have been characterized by employing various techniques including X-ray diffraction, Raman spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, atomic force microscopy, and photoluminescence. Moreover, the mechanism for electron/hole transfer has been focused by a brief electrochemical investigation. The bilayer 1D/2D TiO<sub>2</sub>@MnZnO<sub>3</sub> photoanode exhibited higher current density (2 mA cm<sup>−2</sup>) as compared to pristine TiO<sub>2</sub>-nanotubes (0.174 mA cm<sup>−2</sup>) at 1.52 V vs RHE. The superior photoactivity of heterostructure is attributed to the rapid transfer of photogenerated charge carriers via the Type-II mechanism. Furthermore, the reduced band gap (2.05 eV) accounts for good absorption in the visible region of light, while the interfacial electric field allowed the improved charge separation. The synergistic strategy in the present work demonstrates the promising significance of a heterojunction interface to optimize photovoltaic devices.","PeriodicalId":17364,"journal":{"name":"Journal of The Electrochemical Society","volume":"50 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-03DOI: 10.1149/1945-7111/ad7325
Farah En-Nakra, Demet Uzun, Erdoğan Hasdemir
In this study, we developed a facile and low-cost method to prepare a modified electrode by coating the pencil graphite electrode (PGE) surface with 8-nitroquinoline (8-NQ). The surface modification process was carried out by electrochemical reduction of 8-NQ on the PGE surface in ethanol solution. The optimum conditions were determined for the experimental studies. The differential pulse voltammetry was used to determine rutin with the modified electrode (8-NQ/PGE). The developed electrode showed excellent performance for rutin oxidation in a pH 3.0 Britton Robinson buffer (BR). In this media, linearly increasing anodic peak currents were observed with the concentration of rutin in two wide concentration ranges (i.e., 0.016–0.96 μM and 0.96‒19.73 μM), the sensor showed a low detection limit (i.e., 4.14 nM) (3 s m−1). It displayed good stability and selectivity. Also, it was used successfully for the determination of rutin in orange juice samples.
{"title":"A Novel, Selective, and Fast Electrochemical Sensor Based on an 8-Nitroquinoline-Coated Pencil Graphite Electrode for Rutin Determination in Orange Juice","authors":"Farah En-Nakra, Demet Uzun, Erdoğan Hasdemir","doi":"10.1149/1945-7111/ad7325","DOIUrl":"https://doi.org/10.1149/1945-7111/ad7325","url":null,"abstract":"In this study, we developed a facile and low-cost method to prepare a modified electrode by coating the pencil graphite electrode (PGE) surface with 8-nitroquinoline (8-NQ). The surface modification process was carried out by electrochemical reduction of 8-NQ on the PGE surface in ethanol solution. The optimum conditions were determined for the experimental studies. The differential pulse voltammetry was used to determine rutin with the modified electrode (8-NQ/PGE). The developed electrode showed excellent performance for rutin oxidation in a pH 3.0 Britton Robinson buffer (BR). In this media, linearly increasing anodic peak currents were observed with the concentration of rutin in two wide concentration ranges (i.e., 0.016–0.96 μM and 0.96‒19.73 μM), the sensor showed a low detection limit (i.e., 4.14 nM) (3 s m<sup>−1</sup>). It displayed good stability and selectivity. Also, it was used successfully for the determination of rutin in orange juice samples.<inline-formula>\u0000<inline-graphic xlink:href=\"jesad7325-ga.jpg\" xlink:type=\"simple\"></inline-graphic>\u0000</inline-formula>","PeriodicalId":17364,"journal":{"name":"Journal of The Electrochemical Society","volume":"20 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222437","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The thermal safety of lithium-ion batteries has garnered significant attention due to its pivotal role in the field of new energy. In this work, a three-dimensional electrochemical-thermal coupling model based on the P2D model was established for predicting the thermal performance. The charge-discharge and temperature rise experiments via 18650 cylindrical Li[Ni0.6Co0.2Mn0.2]O2 / graphite batteries are designed to confirm the rationality of the model. The simulation results show that the highest temperature of the battery surface during discharging at 1 C and 4 C are 42.85 °C and 61.25 °C, and the experimental results are 42.50 °C and 62.85 °C, respectively. The electrode heat generation mainly comes from the reaction heat of cathode and anode during 1 C charge process, the maximum power is 1.2 W and 0.6 W, respectively. In the discharge process, the cathode dominates the reaction contribution of 1.02 W and the reaction heat power from the anode is only 0.016 W. The capacity of heat dissipation can be increased by enhancing the convective heat transfer coefficient and air velocity within a reasonable range. The proposed electrochemical-thermal coupling model is valuable to evaluate the heat behavior and promote the battery development.
由于锂离子电池在新能源领域发挥着举足轻重的作用，因此其热安全问题备受关注。本研究建立了基于 P2D 模型的三维电化学-热耦合模型，用于预测电池的热性能。设计了 18650 圆柱形锂[Ni0.6Co0.2Mn0.2]O2 / 石墨电池的充放电和温升实验，以证实模型的合理性。模拟结果表明，在 1 C 和 4 C 放电时，电池表面的最高温度分别为 42.85 ℃ 和 61.25 ℃，而实验结果分别为 42.50 ℃ 和 62.85 ℃。在 1 C 充电过程中，电极发热主要来自阴极和阳极的反应热，最大功率分别为 1.2 W 和 0.6 W。在放电过程中，阴极的反应热量占主导地位，为 1.02 W，而阳极的反应热量仅为 0.016 W。所提出的电化学-热耦合模型对评估热行为和促进电池开发具有重要价值。
{"title":"Thermal Performance of a Cylindrical Li[Ni0.6Co0.2Mn0.2]O2/Graphite Battery based on the Electrochemical-Thermal Coupling Model","authors":"Chao Zhang, Jin Shang, Yonglian Xiong, Ting Yi, Quanhui Hou, Xing Qian","doi":"10.1149/1945-7111/ad7290","DOIUrl":"https://doi.org/10.1149/1945-7111/ad7290","url":null,"abstract":"The thermal safety of lithium-ion batteries has garnered significant attention due to its pivotal role in the field of new energy. In this work, a three-dimensional electrochemical-thermal coupling model based on the P2D model was established for predicting the thermal performance. The charge-discharge and temperature rise experiments via 18650 cylindrical Li[Ni<sub>0.6</sub>Co<sub>0.2</sub>Mn<sub>0.2</sub>]O<sub>2</sub> / graphite batteries are designed to confirm the rationality of the model. The simulation results show that the highest temperature of the battery surface during discharging at 1 C and 4 C are 42.85 °C and 61.25 °C, and the experimental results are 42.50 °C and 62.85 °C, respectively. The electrode heat generation mainly comes from the reaction heat of cathode and anode during 1 C charge process, the maximum power is 1.2 W and 0.6 W, respectively. In the discharge process, the cathode dominates the reaction contribution of 1.02 W and the reaction heat power from the anode is only 0.016 W. The capacity of heat dissipation can be increased by enhancing the convective heat transfer coefficient and air velocity within a reasonable range. The proposed electrochemical-thermal coupling model is valuable to evaluate the heat behavior and promote the battery development.","PeriodicalId":17364,"journal":{"name":"Journal of The Electrochemical Society","volume":"20 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-02DOI: 10.1149/1945-7111/ad728c
Dalong Tan, Hong Zhang, Zhaoguang Ma, Xia Zheng, Jing Liu, Fanyong Meng, Min Yang
To address the typical structural defects that are prone to occur during the preparation and storage processes of thermal battery, experiments of battery image acquisition were designed based on X-ray computed tomography system. An improved Yolov5s network was employed to achieve high-precision automatic detection of typical defects. Through the discharge experiment of thermal battery, discharge performance curves of normal batteries and three defective batteries were constructed. The impact and mechanisms of different defects on the discharge performance were analyzed based on the voltage curve. By designing an automatic stitching scheme, the phenomenon of interlayer information overlap caused by the increase of cone angle in digital radiography images was suppressed. To address the issues of low image contrast and limited defect data in thermal battery imaging, the defect dataset was expanded using the designed image preprocessing steps and improving the contrast of the images. For subtle defects that are difficult to identify, the introduced multi-head self-attention mechanism in Transformer and the use of Focal Loss instead of cross-entropy loss function were employed to improve the recognition accuracy of subtle defects while ensuring the detection speed. The comparative experiment shows that the improved network model has higher recognition accuracy compared to Faster R-CNN, SSD, Cascade R-CNN, EfficientDet and the original Yolov5s network. The recognition accuracy of typical defects in thermal batteries can reach 98.7%.
针对热电池在制备和储存过程中容易出现的典型结构缺陷，设计了基于 X 射线计算机断层扫描系统的电池图像采集实验。采用改进的 Yolov5s 网络实现了典型缺陷的高精度自动检测。通过热电池放电实验，构建了正常电池和三种缺陷电池的放电性能曲线。根据电压曲线分析了不同缺陷对放电性能的影响和机理。通过设计自动拼接方案，抑制了数字射线摄影图像因锥角增大而导致的层间信息重叠现象。针对热电池成像中图像对比度低和缺陷数据有限的问题，利用设计的图像预处理步骤扩大了缺陷数据集，提高了图像的对比度。针对难以识别的细微缺陷，在 Transformer 中引入了多头自注意机制，并使用 Focal Loss 代替交叉熵损失函数，在保证检测速度的同时提高了细微缺陷的识别精度。对比实验表明，与 Faster R-CNN、SSD、Cascade R-CNN、EfficientDet 和原始 Yolov5s 网络相比，改进后的网络模型具有更高的识别精度。对热电池典型缺陷的识别准确率可达 98.7%。
{"title":"Thermal Battery Multi-Defects Detection and Discharge Performance Analysis Based on Computed Tomography Imaging","authors":"Dalong Tan, Hong Zhang, Zhaoguang Ma, Xia Zheng, Jing Liu, Fanyong Meng, Min Yang","doi":"10.1149/1945-7111/ad728c","DOIUrl":"https://doi.org/10.1149/1945-7111/ad728c","url":null,"abstract":"To address the typical structural defects that are prone to occur during the preparation and storage processes of thermal battery, experiments of battery image acquisition were designed based on X-ray computed tomography system. An improved Yolov5s network was employed to achieve high-precision automatic detection of typical defects. Through the discharge experiment of thermal battery, discharge performance curves of normal batteries and three defective batteries were constructed. The impact and mechanisms of different defects on the discharge performance were analyzed based on the voltage curve. By designing an automatic stitching scheme, the phenomenon of interlayer information overlap caused by the increase of cone angle in digital radiography images was suppressed. To address the issues of low image contrast and limited defect data in thermal battery imaging, the defect dataset was expanded using the designed image preprocessing steps and improving the contrast of the images. For subtle defects that are difficult to identify, the introduced multi-head self-attention mechanism in Transformer and the use of Focal Loss instead of cross-entropy loss function were employed to improve the recognition accuracy of subtle defects while ensuring the detection speed. The comparative experiment shows that the improved network model has higher recognition accuracy compared to Faster R-CNN, SSD, Cascade R-CNN, EfficientDet and the original Yolov5s network. The recognition accuracy of typical defects in thermal batteries can reach 98.7%.<inline-formula>\u0000<inline-graphic xlink:href=\"jesad728c-ga.jpg\" xlink:type=\"simple\"></inline-graphic>\u0000</inline-formula>","PeriodicalId":17364,"journal":{"name":"Journal of The Electrochemical Society","volume":"183 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Reduction of the nickel oxide-yttria stabilized zirconia (NiO-YSZ) anode is a significant step before the operation of a solid oxide fuel cell (SOFC). However, phenomena which occur during the reduction and their mechanism analyses are not summarized sufficiently. In this study, we investigated the influence of the hydrogen concentration, water vapor concentration of the reduction gas, Y2O3 content of the YSZ material of the anode, and temperature on the reduction process. The results showed that water vapor added to the hydrogen during reduction caused a temporary stasis period of the open circuit voltage. The length of the temporary stasis period was almost irrelevant to the water vapor concentration. During reduction, the length of the temporary stasis period of the open circuit voltage was negatively associated with hydrogen concentration and temperature, but positively associated with Y2O3 content of the YSZ material of the anode. After reduction, the SOFC showed better initial performance when the hydrogen concentration or the water vapor concentration during the reduction were higher. The classical shrinking core model can be used to explain these phenomena.
{"title":"Mechanism Analysis of the Reduction Process of the NiO-YSZ Anode of a Solid Oxide Fuel Cell by Hydrogen","authors":"Xiaoyu Wang, Yongliang Zhang, Haiming Zhang, Wenwan Song, Tatsuya Kawada, Zewei Lyu, Minfang Han","doi":"10.1149/1945-7111/ad6bc2","DOIUrl":"https://doi.org/10.1149/1945-7111/ad6bc2","url":null,"abstract":"Reduction of the nickel oxide-yttria stabilized zirconia (NiO-YSZ) anode is a significant step before the operation of a solid oxide fuel cell (SOFC). However, phenomena which occur during the reduction and their mechanism analyses are not summarized sufficiently. In this study, we investigated the influence of the hydrogen concentration, water vapor concentration of the reduction gas, Y<sub>2</sub>O<sub>3</sub> content of the YSZ material of the anode, and temperature on the reduction process. The results showed that water vapor added to the hydrogen during reduction caused a temporary stasis period of the open circuit voltage. The length of the temporary stasis period was almost irrelevant to the water vapor concentration. During reduction, the length of the temporary stasis period of the open circuit voltage was negatively associated with hydrogen concentration and temperature, but positively associated with Y<sub>2</sub>O<sub>3</sub> content of the YSZ material of the anode. After reduction, the SOFC showed better initial performance when the hydrogen concentration or the water vapor concentration during the reduction were higher. The classical shrinking core model can be used to explain these phenomena.","PeriodicalId":17364,"journal":{"name":"Journal of The Electrochemical Society","volume":"58 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142222432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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