Pub Date : 2024-11-13DOI: 10.1016/j.electacta.2024.145352
Hossein Esfandian, Mohammad Mojtaba Sadeghi
In this study, various mixed-linker metal-organic frameworks (MOFs) based on Zn-MOF were successfully synthesized using different ratios of 1,3,5-benzenetricarboxylic acid (BTC) and 1,4-benzenedicarboxylic acid (BDC) as modulator ligands. The characterization results indicated that a lower percentage of BDC ligand effectively enhances the specific surface area of the MOFs while maintaining their microporous structure. Furthermore, the supercapacitive behavior of the synthesized Zn-MOFs with varying mixed ligand ratios was evaluated through electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and galvanostatic charge-discharge (GCD) measurements in a 6 M KOH electrolyte. Synthesized materials, namely MOF-0 (100 % BTC), MOF-1 (75 % BTC, 25 % BDC), MOF-2 (50 % BTC, 50 % BDC), MOF-3 (25 % BTC, 75 % BDC), and MOF-4 (100 % BDC) were assessed through GCD tests. These tests demonstrated specific capacitance values of 577, 683, 529, 428, and 302 F/g at a current density of 0.5 A/g, respectively. This impressive performance underscores the effectiveness of the mixed-linker strategy in optimizing the electrochemical properties of MOF for energy storage applications.
{"title":"Preparation and application of mixed ligand Zn-MOF as electrode materials for supercapacitors applications","authors":"Hossein Esfandian, Mohammad Mojtaba Sadeghi","doi":"10.1016/j.electacta.2024.145352","DOIUrl":"10.1016/j.electacta.2024.145352","url":null,"abstract":"<div><div>In this study, various mixed-linker metal-organic frameworks (MOFs) based on Zn-MOF were successfully synthesized using different ratios of 1,3,5-benzenetricarboxylic acid (BTC) and 1,4-benzenedicarboxylic acid (BDC) as modulator ligands. The characterization results indicated that a lower percentage of BDC ligand effectively enhances the specific surface area of the MOFs while maintaining their microporous structure. Furthermore, the supercapacitive behavior of the synthesized Zn-MOFs with varying mixed ligand ratios was evaluated through electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and galvanostatic charge-discharge (GCD) measurements in a 6 M KOH electrolyte. Synthesized materials, namely MOF-0 (100 % BTC), MOF-1 (75 % BTC, 25 % BDC), MOF-2 (50 % BTC, 50 % BDC), MOF-3 (25 % BTC, 75 % BDC), and MOF-4 (100 % BDC) were assessed through GCD tests. These tests demonstrated specific capacitance values of 577, 683, 529, 428, and 302 F/g at a current density of 0.5 A/g, respectively. This impressive performance underscores the effectiveness of the mixed-linker strategy in optimizing the electrochemical properties of MOF for energy storage applications.</div></div>","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"509 ","pages":"Article 145352"},"PeriodicalIF":5.5,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142601802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Aluminum-tantalum powders are emerging as new raw materials for additive manufacturing (AM) technologies, but their preparation in bulk quantities and in powder form via conventional metallurgical methods is challenging. In this study, we report a one-step synthesis of spherical Al3Ta powder by direct electrolyzing solid Ta2O5 cathode (vs. a graphite anode) in molten Na3AlF6-K3AlF6-AlF3-LiF-Al2O3. Cyclic voltammetry and constant potential electrolysis techniques were employed to characterize the electrochemical reaction process, along with X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) for the structural and morphological analyses. The process involves an initial Ta2O5 electro-deoxygenation process, the subsequent electrodeposition of Al3+ on the formed Ta particles and an in-situ alloying process. The innovative use of Ta2O5 cathodes with a novel hierarchical porous structure allows for a controlled transformation of cathode particle morphology and facilitates the rapid generation of nanoscale tantalum particles. Al3+ from the electrolyte is then electrodeposited onto these particles, initiating an in-situ alloying reaction. This is an exothermic process that facilitates the diffusion of aluminum atoms into tantalum, and reduces the interfacial energy promoting the formation of spherical Al3Ta particles. Such powders are in demand for AM techniques. The findings may now guide the way to establishing the electrochemical route for the short-process preparation of other high-temperature alloy powders.
铝钽粉末正在成为增材制造（AM）技术的新型原材料，但通过传统冶金方法制备大量粉末状铝钽粉末具有挑战性。在本研究中，我们报告了通过在熔融 Na3AlF6-K3AlF6-AlF3-LiF-Al2O3 中直接电解固体 Ta2O5 阴极（相对于石墨阳极）一步合成球形 Al3Ta 粉末的方法。采用循环伏安法和恒电位电解技术来表征电化学反应过程，并用 X 射线衍射 (XRD)、扫描电子显微镜 (SEM) 和透射电子显微镜 (TEM) 进行结构和形态分析。该过程包括最初的 Ta2O5 电脱氧过程、随后在形成的 Ta 粒子上电沉积 Al3+ 以及原位合金化过程。创新性地使用具有新型分层多孔结构的 Ta2O5 阴极可以控制阴极颗粒形态的变化，并促进纳米级钽颗粒的快速生成。然后将电解液中的 Al3+ 电沉积到这些颗粒上，引发原位合金化反应。这是一个放热过程，有利于铝原子向钽中扩散，并降低界面能，促进球形 Al3Ta 颗粒的形成。这种粉末是 AM 技术所需要的。现在，这些发现可为建立电化学路线，以短时间制备其他高温合金粉末提供指导。
{"title":"One-step synthesis of spherical Al3Ta alloy powder by electrolyzing solid Ta2O5 in molten fluorides","authors":"Yapeng Kong, Longdi Ma, Heng Zhang, Xiwen Chen, Xuemin Liang, Liqiang Wang, Yangyang Fan, Yuran Chen","doi":"10.1016/j.electacta.2024.145354","DOIUrl":"10.1016/j.electacta.2024.145354","url":null,"abstract":"<div><div>Aluminum-tantalum powders are emerging as new raw materials for additive manufacturing (AM) technologies, but their preparation in bulk quantities and in powder form via conventional metallurgical methods is challenging. In this study, we report a one-step synthesis of spherical Al<sub>3</sub>Ta powder by direct electrolyzing solid Ta<sub>2</sub>O<sub>5</sub> cathode (<em>vs</em>. a graphite anode) in molten Na<sub>3</sub>AlF<sub>6</sub>-K<sub>3</sub>AlF<sub>6</sub>-AlF<sub>3</sub>-LiF-Al<sub>2</sub>O<sub>3</sub>. Cyclic voltammetry and constant potential electrolysis techniques were employed to characterize the electrochemical reaction process, along with X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) for the structural and morphological analyses. The process involves an initial Ta<sub>2</sub>O<sub>5</sub> electro-deoxygenation process, the subsequent electrodeposition of Al<sup>3+</sup> on the formed Ta particles and an in-situ alloying process. The innovative use of Ta<sub>2</sub>O<sub>5</sub> cathodes with a novel hierarchical porous structure allows for a controlled transformation of cathode particle morphology and facilitates the rapid generation of nanoscale tantalum particles. Al<sup>3+</sup> from the electrolyte is then electrodeposited onto these particles, initiating an in-situ alloying reaction. This is an exothermic process that facilitates the diffusion of aluminum atoms into tantalum, and reduces the interfacial energy promoting the formation of spherical Al<sub>3</sub>Ta particles. Such powders are in demand for AM techniques. The findings may now guide the way to establishing the electrochemical route for the short-process preparation of other high-temperature alloy powders.</div></div>","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"510 ","pages":"Article 145354"},"PeriodicalIF":5.5,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142601800","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-13DOI: 10.1016/j.electacta.2024.145353
Li He, Jiao Peng, Xiaolin Liu, Peng Liu, Juan Yang, Yi Tang, Xianyou Wang
Graphene as conductive additives for enhancing the electrochemical performance of commercial cathode materials (e.g., LiFePO4, LiCoO2, and LiMn2O4) in advanced Li-ion batteries (LIBs) has attracted great attention in recent years. However, the LiFePO4 and LiCoO2 electrodes usually show a poor rate capability when using graphene as the conductive additive, since its planar structure hinders ion transmission. Herein, a variety of reduced graphene oxides (rGO-x) have been successfully prepared using the modified Hummer's method followed by calcination. The results show that due to a large specific area and moderate defect density, rGO-5 can ensure good enough interfacial contact between active material particles and collector, thus maintaining fast electron/ion transportation. It has been found that LiFePO4 and LiCoO2 electrodes exhibit good lithium storage properties of 160.95 and 139.41 mA h g-1 at a rate of 0.1 C when rGO-5 is utilized as a conductivity additive. Meanwhile, combined with the electrochemical impedance and kinetic exploration, it can be seen that the LiFePO4 and LiCoO2 electrodes demonstrate a high Li+ diffusion coefficient (DLi+) of 6.7 × 10-14 cm2 s-1 and 4.3 × 10-13 cm2 s-1, respectively. Therefore, this research sheds new light on the practical utilization of rGO additives in high-performance lithium-ion batteries.
{"title":"The reduced graphene oxide conductive additives with a certain defect concentration enabling rate-capability of lithium-ion batteries","authors":"Li He, Jiao Peng, Xiaolin Liu, Peng Liu, Juan Yang, Yi Tang, Xianyou Wang","doi":"10.1016/j.electacta.2024.145353","DOIUrl":"https://doi.org/10.1016/j.electacta.2024.145353","url":null,"abstract":"Graphene as conductive additives for enhancing the electrochemical performance of commercial cathode materials (e.g., LiFePO<sub>4</sub>, LiCoO<sub>2</sub>, and LiMn<sub>2</sub>O<sub>4</sub>) in advanced Li-ion batteries (LIBs) has attracted great attention in recent years. However, the LiFePO<sub>4</sub> and LiCoO<sub>2</sub> electrodes usually show a poor rate capability when using graphene as the conductive additive, since its planar structure hinders ion transmission. Herein, a variety of reduced graphene oxides (rGO-x) have been successfully prepared using the modified Hummer's method followed by calcination. The results show that due to a large specific area and moderate defect density, rGO-5 can ensure good enough interfacial contact between active material particles and collector, thus maintaining fast electron/ion transportation. It has been found that LiFePO<sub>4</sub> and LiCoO<sub>2</sub> electrodes exhibit good lithium storage properties of 160.95 and 139.41 mA h g<sup>-1</sup> at a rate of 0.1 C when rGO-5 is utilized as a conductivity additive. Meanwhile, combined with the electrochemical impedance and kinetic exploration, it can be seen that the LiFePO<sub>4</sub> and LiCoO<sub>2</sub> electrodes demonstrate a high Li<sup>+</sup> diffusion coefficient (D<sub>Li+</sub>) of 6.7 × 10<sup>-14</sup> cm<sup>2</sup> s<sup>-1</sup> and 4.3 × 10<sup>-13</sup> cm<sup>2</sup> s<sup>-1</sup>, respectively. Therefore, this research sheds new light on the practical utilization of rGO additives in high-performance lithium-ion batteries.","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"34 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142601803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-12DOI: 10.1016/j.electacta.2024.145350
Debasa Mukherjee, Lucinda Elizabeth Doyle
Microbial electroactivity in elevated salt conditions is seldom studied, despite both fundamental and applied relevance. This work reports the enrichment of electroactive microorganisms under saline conditions (2% NaCl), performed on screen-printed carbon electrodes with applied anodic potential. From the weakly electroactive enriched community, three halotolerant electroactive isolates were obtained in pure culture and identified via 16S rRNA gene sequencing. Two isolates were Gram positive (proposed names Micrococcus sp. YH-1 and Gordonia sp. RH-1) and one was Gram negative (proposed name Stutzerimonas sp. CH-1). The isolates were electrochemically characterised on conventional carbon felt electrodes using chronoamperometry. After two days of growth, a current density of 8.29 ± 0.85 μA/cm2 was observed in Micrococcus sp. YH-1, comparable to reported values for the model electroactive microorganism Shewanella oneidensis. Gordonia sp. RH-1 and Stutzerimonas sp. CH-1 appeared to be weak electricigens due to their low current output (2.19 ± 0.46 μA/cm2 and 1.73 ± 0.47 μA/cm2, respectively). The isolates are notable as there are very limited reports of electroactivity in the genera Micrococcus and Gordonia. Cyclic voltammetry revealed prominent redox peaks in Micrococcus sp. YH-1 and Stutzerimonas sp. CH-1. Scanning electron microscopy demonstrated colonisation of the electrode by each isolate, along with thin cellular appendages in Micrococcus sp. YH-1 and Stutzerimonas sp. CH-1. This work extends the catalogue of characterised halotolerant electroactive microbes while also enhancing our understanding of weak electricigens, extracellular electron transfer in Gram positives, and the inherent electroactivity of the natural environment.
{"title":"Electrochemical enrichment of a community of weak electricigens and characterisation of three halotolerant electroactive isolates: Micrococcus sp. YH-1, Gordonia sp. RH-1 and Stutzerimonas sp. CH-1","authors":"Debasa Mukherjee, Lucinda Elizabeth Doyle","doi":"10.1016/j.electacta.2024.145350","DOIUrl":"https://doi.org/10.1016/j.electacta.2024.145350","url":null,"abstract":"Microbial electroactivity in elevated salt conditions is seldom studied, despite both fundamental and applied relevance. This work reports the enrichment of electroactive microorganisms under saline conditions (2% NaCl), performed on screen-printed carbon electrodes with applied anodic potential. From the weakly electroactive enriched community, three halotolerant electroactive isolates were obtained in pure culture and identified via 16S rRNA gene sequencing. Two isolates were Gram positive (proposed names <em>Micrococcus</em> sp. YH-1 and <em>Gordonia</em> sp. RH-1) and one was Gram negative (proposed name <em>Stutzerimonas</em> sp. CH-1). The isolates were electrochemically characterised on conventional carbon felt electrodes using chronoamperometry. After two days of growth, a current density of 8.29 ± 0.85 μA/cm<sup>2</sup> was observed in <em>Micrococcus</em> sp. YH-1, comparable to reported values for the model electroactive microorganism <em>Shewanella oneidensis. Gordonia</em> sp. RH-1 and <em>Stutzerimonas</em> sp. CH-1 appeared to be weak electricigens due to their low current output (2.19 ± 0.46 μA/cm<sup>2</sup> and 1.73 ± 0.47 μA/cm<sup>2</sup>, respectively). The isolates are notable as there are very limited reports of electroactivity in the genera <em>Micrococcus</em> and <em>Gordonia</em>. Cyclic voltammetry revealed prominent redox peaks in <em>Micrococcus</em> sp. YH-1 and <em>Stutzerimonas</em> sp. CH-1. Scanning electron microscopy demonstrated colonisation of the electrode by each isolate, along with thin cellular appendages in <em>Micrococcus</em> sp. YH-1 and <em>Stutzerimonas</em> sp. CH-1. This work extends the catalogue of characterised halotolerant electroactive microbes while also enhancing our understanding of weak electricigens, extracellular electron transfer in Gram positives, and the inherent electroactivity of the natural environment.","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"35 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142601805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-12DOI: 10.1016/j.electacta.2024.145348
Guangzhe Wang, Gongwei Wang, Lin Zhuang, Li Xiao
Polyelectrolytes (PEs) serve as the critical medium for electrochemical reactions in membrane-based electrochemical devices, such as fuel cells and membrane electrolyzers. To optimize membrane-based electrochemical device performance and elucidate reaction mechanisms, there is a pressing need for detailed microscopic molecular information at gas diffusion electrode/PE interfaces. In this work, we designed a novel membrane-based-electrochemical-device-like gas diffusion electrode/polyelectrolyte electrochemical in-situ Raman cell. The cell's configuration and gas transfer characteristics closely mimic those of MBEDs under working conditions. We created a Pt/Nafion(s) interface by hot-pressing satellite Au@SiO2-Pt loaded carbon cloth with a Nafion membrane, and used this interface for electrochemical in-situ surface enhanced Raman spectroscopy (SERS) observation, including oxygen adsorption/desorption processes, structure of interfacial water and functional groups of Nafion under Ar. The cell enables negatively polarize the potential down to -1.6 V vs. RHE without stripping of the solid/solid interface, despite vigorous H2 generation. The stability of the interface under extreme conditions demonstrates rapid gas transfer at the interface. This observation underscores the potential of our in-situ Raman cell for studying various gas-involved reactions under conditions that closely resemble those in operational MBEDs.
{"title":"In-situ Raman Observation on Gas Diffusion Electrode/Polyelectrolyte Interface","authors":"Guangzhe Wang, Gongwei Wang, Lin Zhuang, Li Xiao","doi":"10.1016/j.electacta.2024.145348","DOIUrl":"https://doi.org/10.1016/j.electacta.2024.145348","url":null,"abstract":"Polyelectrolytes (PEs) serve as the critical medium for electrochemical reactions in membrane-based electrochemical devices, such as fuel cells and membrane electrolyzers. To optimize membrane-based electrochemical device performance and elucidate reaction mechanisms, there is a pressing need for detailed microscopic molecular information at gas diffusion electrode/PE interfaces. In this work, we designed a novel membrane-based-electrochemical-device-like gas diffusion electrode/polyelectrolyte electrochemical <em>in-situ</em> Raman cell. The cell's configuration and gas transfer characteristics closely mimic those of MBEDs under working conditions. We created a Pt/Nafion(<em>s</em>) interface by hot-pressing satellite Au@SiO<sub>2</sub>-Pt loaded carbon cloth with a Nafion membrane, and used this interface for electrochemical <em>in-situ</em> surface enhanced Raman spectroscopy (SERS) observation, including oxygen adsorption/desorption processes, structure of interfacial water and functional groups of Nafion under Ar. The cell enables negatively polarize the potential down to -1.6 V vs. RHE without stripping of the solid/solid interface, despite vigorous H<sub>2</sub> generation. The stability of the interface under extreme conditions demonstrates rapid gas transfer at the interface. This observation underscores the potential of our <em>in-situ</em> Raman cell for studying various gas-involved reactions under conditions that closely resemble those in operational MBEDs.","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"80 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142599869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ion diffusion and electron transfer are hindered by commonly used hydrophobic binders, which directly affect the electrochemical performance of the electrodes. Hydrophilic binders are selected to efficaciously solve the problem of relatively low actual specific capacitance and rate performance in the field of nickel cobalt sulfide electrode materials. In the paper, RuCoNiS electrodes were prepared using polytetrafluoroethylene (PTFE), carboxymethyl cellulose (CMC), xanthan gum (XG), and chitosan (CS) as binders. The surface wettability, morphological structure, specific surface area, and electrochemical performance of electrodes with different binders were analyzed by XRD, SEM, BET, CV, GCD, and EIS, etc. It's shown that the synthesis of CoNi2S is confirmed by XRD. The XPS results verify the existence of RuO2 and Ni2+/Ni3+ and Co2+/Co3+ redox couples. A cross-linked network structure is formed on the surface of the RuCoNiS by CS. The CS-RuCoNiS electrode has the largest specific surface area and microporosity. Ion migration in the electrolyte is facilitated by the excellent wettability of the CS-RuCoNiS electrode. The CS-RuCoNiS electrode reachs 1193.52 F g-1, which is 1.74 times higher than that of the PTFE-RuCoNiS electrode at 1 A g-1. The CS binder with its three-dimensional structure has the highest ionic conductivity of 2.29 × 10-4 S cm-1, a lower Rct, good cycling stability with a capacity retention of 84.3% after 5000 cycles at 200 mV s-1, and excellent rate performance of 85.6%. It can provide a practical application in supercapacitors.
{"title":"Biopolymers as three-dimensional structural binders for nickel-cobalt sulfide supercapacitor electrodes","authors":"Jiamei Li, Zhe Chen, Fuqiang Chen, Zhijin Zhu, Tongwei Shen, Yunxiang Chen, Yaliang Chen, Yanqun Shao","doi":"10.1016/j.electacta.2024.145345","DOIUrl":"https://doi.org/10.1016/j.electacta.2024.145345","url":null,"abstract":"Ion diffusion and electron transfer are hindered by commonly used hydrophobic binders, which directly affect the electrochemical performance of the electrodes. Hydrophilic binders are selected to efficaciously solve the problem of relatively low actual specific capacitance and rate performance in the field of nickel cobalt sulfide electrode materials. In the paper, RuCoNiS electrodes were prepared using polytetrafluoroethylene (PTFE), carboxymethyl cellulose (CMC), xanthan gum (XG), and chitosan (CS) as binders. The surface wettability, morphological structure, specific surface area, and electrochemical performance of electrodes with different binders were analyzed by XRD, SEM, BET, CV, GCD, and EIS, etc. It's shown that the synthesis of CoNi<sub>2</sub>S is confirmed by XRD. The XPS results verify the existence of RuO<sub>2</sub> and Ni<sup>2+</sup>/Ni<sup>3+</sup> and Co<sup>2+</sup>/Co<sup>3+</sup> redox couples. A cross-linked network structure is formed on the surface of the RuCoNiS by CS. The CS-RuCoNiS electrode has the largest specific surface area and microporosity. Ion migration in the electrolyte is facilitated by the excellent wettability of the CS-RuCoNiS electrode. The CS-RuCoNiS electrode reachs 1193.52 F g<sup>-1</sup>, which is 1.74 times higher than that of the PTFE-RuCoNiS electrode at 1 A g<sup>-1</sup>. The CS binder with its three-dimensional structure has the highest ionic conductivity of 2.29 × 10<sup>-4</sup> S cm<sup>-1</sup>, a lower R<sub>ct</sub>, good cycling stability with a capacity retention of 84.3% after 5000 cycles at 200 mV s<sup>-1</sup>, and excellent rate performance of 85.6%. It can provide a practical application in supercapacitors.","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"148 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142596622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-10DOI: 10.1016/j.electacta.2024.145346
Kevin J. Kurian, Justynne Fabian, John Cassidy, Anthony Betts
The voltammetric behaviour of diclofenac and mefenamic acid at a screen printed carbon electrode is very similar and both compounds share a similar molecular structure to that of diphenylamine. In each case on repeated scanning, an electroactive film is deposited due to the polymerisation of either of the molecules. The resultant film adheres to the electrode and is stable in aqueous solution for both diclofenac and mefenamic acid. This film formation is unique to a carbon electrode as no layers were found to form on Pt or Au. The formal potential of the confined layer shifts with pH, with a slope of about -59mV/pH unit. Such layers will prevent the multiple use of the electrode in quantitative analysis unless it is cleaned between runs. A model based on the polymer formation from a diphenylamine backbone is proposed.
{"title":"A Critical Analysis of the Voltammetry of Fenamic acids: Evidence of diclofenac and mefenamic acid electroactive film formation","authors":"Kevin J. Kurian, Justynne Fabian, John Cassidy, Anthony Betts","doi":"10.1016/j.electacta.2024.145346","DOIUrl":"https://doi.org/10.1016/j.electacta.2024.145346","url":null,"abstract":"The voltammetric behaviour of diclofenac and mefenamic acid at a screen printed carbon electrode is very similar and both compounds share a similar molecular structure to that of diphenylamine. In each case on repeated scanning, an electroactive film is deposited due to the polymerisation of either of the molecules. The resultant film adheres to the electrode and is stable in aqueous solution for both diclofenac and mefenamic acid. This film formation is unique to a carbon electrode as no layers were found to form on Pt or Au. The formal potential of the confined layer shifts with pH, with a slope of about -59mV/pH unit. Such layers will prevent the multiple use of the electrode in quantitative analysis unless it is cleaned between runs. A model based on the polymer formation from a diphenylamine backbone is proposed.","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"18 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142596621","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-09DOI: 10.1016/j.electacta.2024.145341
Shulin Li , Qiaoquan Lin , Han Yan , Qiaodong Li , Yu Yang , Xinlin Yan , Zhenyu Wang , Chuang Yu , Long Zhang
Cl-rich Li-argyrodites are one type of sulfide solid electrolytes (SSEs) with a high ionic conductivity and suitable mechanical properties for practical application. However, their tolerance against moisture in air and compatibility with metallic Li need further improvements. Here, we demonstrate that Nb-O dual-doping can be a good strategy for advanced Cl-rich Li-argyrodite SSEs, prepared by high energy ball milling and annealing method. Our results show that the Nb-O co-doping enhances the interface compatibility towards metallic Li and improves the moisture resistance, while maintains a fast ion transport. The Nb-O incorporation improves the Young's modulus and mitigates the side reaction of Li-argyrodite with Li. The doping-optimized sample demonstrates a high critical current density of 2.28 mA cm−2 and a long-term Li plating/stripping stability under a relatively high current density (1 mA cm−2) for nearly 3000 cycles. Notably, the corresponding all-solid-state lithium batteries (ASSLBs), using a Li metal electrode, can maintain a superior cycling stability for over 1000 cycles at 1 C.
富含锂离子的硫化物固态电解质（SSE）具有很高的离子电导率和适合实际应用的机械性能。然而，它们对空气中湿气的耐受性以及与金属锂的兼容性还需要进一步改进。在此，我们证明了 Nb-O 双掺杂是一种通过高能球磨和退火法制备富含 Cli-argyrodite 的先进锂离子固态电解质的良好策略。我们的研究结果表明，Nb-O 共掺杂增强了与金属锂的界面相容性，提高了耐湿性，同时保持了离子的快速传输。Nb-O 的掺入提高了杨氏模量，并减轻了锂阳起石与锂的副反应。经过掺杂优化的样品临界电流密度高达 2.28 mA cm-2，在相对较高的电流密度（1 mA cm-2）下，锂镀层/剥离具有近 3000 次循环的长期稳定性。值得注意的是，使用锂金属电极的相应全固态锂电池（ASSLBs）可在 1 C 下保持超过 1000 次循环的卓越稳定性。
{"title":"Enhanced air stability and interface compatibility in Nb-O-doped Cl-rich Li-argyrodites for all-solid-state Li metal batteries","authors":"Shulin Li , Qiaoquan Lin , Han Yan , Qiaodong Li , Yu Yang , Xinlin Yan , Zhenyu Wang , Chuang Yu , Long Zhang","doi":"10.1016/j.electacta.2024.145341","DOIUrl":"10.1016/j.electacta.2024.145341","url":null,"abstract":"<div><div>Cl-rich Li-argyrodites are one type of sulfide solid electrolytes (SSEs) with a high ionic conductivity and suitable mechanical properties for practical application. However, their tolerance against moisture in air and compatibility with metallic Li need further improvements. Here, we demonstrate that Nb-O dual-doping can be a good strategy for advanced Cl-rich Li-argyrodite SSEs, prepared by high energy ball milling and annealing method. Our results show that the Nb-O co-doping enhances the interface compatibility towards metallic Li and improves the moisture resistance, while maintains a fast ion transport. The Nb-O incorporation improves the Young's modulus and mitigates the side reaction of Li-argyrodite with Li. The doping-optimized sample demonstrates a high critical current density of 2.28 mA cm<sup>−2</sup> and a long-term Li plating/stripping stability under a relatively high current density (1 mA cm<sup>−2</sup>) for nearly 3000 cycles. Notably, the corresponding all-solid-state lithium batteries (ASSLBs), using a Li metal electrode, can maintain a superior cycling stability for over 1000 cycles at 1 C.</div></div>","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"509 ","pages":"Article 145341"},"PeriodicalIF":5.5,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142596628","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This work reports the synthesis of copper- and cobalt-based coupled and mixed metal oxides (CuO-Co3O4 and CuCo2O4, respectively) utilizing a simple hydrothermal and calcination approach. CuO-Co3O4, CuCo2O4, and the control samples were characterized by powder X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray, and X-ray photoelectron spectroscopy. TEM and FE-SEM analyses of CuO-Co3O4 reveal the presence of two distinct morphologies: rod- and sphere-shaped particles (CuO and Co3O4, respectively). Further, CuO-Co3O4 was efficiently utilized as an electrocatalyst for the selective oxidation of hydrazine (Hyz). CuO-Co3O4 shows a high redox response compared to CuO, Co3O4, CuCo2O4, and the physical mixture of CuO and Co3O4 (CuO/Co3O4). This enhanced performance is attributed to the synergistic interaction between the metal ions caused by their close proximity and the increased exposure of surface active sites. CuO-Co3O4 shows a broad linear range (1–3500 µM), a low detection limit (0.29 µM), and high sensitivity (0.5756 µA µM-1 cm-2) for the Hyz determination. Kinetic parameters, for instance the diffusion coefficient and catalytic rate constant for Hyz oxidation were obtained using chronoamperometry. Additionally, CuO-Co3O4 was effectively utilized to analyze Hyz in real samples with acceptable recovery rates.
{"title":"A comparative study on the electrocatalytic efficiency of coupled (CuO-Co3O4) vs. mixed (CuCo2O4) metal oxides: Probed by hydrazine oxidation and sensitive determination","authors":"Smita Singh, Varsha Singh, Vikram Rathour, Vellaichamy Ganesan","doi":"10.1016/j.electacta.2024.145337","DOIUrl":"10.1016/j.electacta.2024.145337","url":null,"abstract":"<div><div>This work reports the synthesis of copper- and cobalt-based coupled and mixed metal oxides (CuO-Co<sub>3</sub>O<sub>4</sub> and CuCo<sub>2</sub>O<sub>4</sub>, respectively) utilizing a simple hydrothermal and calcination approach. CuO-Co<sub>3</sub>O<sub>4</sub>, CuCo<sub>2</sub>O<sub>4</sub>, and the control samples were characterized by powder X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray, and X-ray photoelectron spectroscopy. TEM and FE-SEM analyses of CuO-Co<sub>3</sub>O<sub>4</sub> reveal the presence of two distinct morphologies: rod- and sphere-shaped particles (CuO and Co<sub>3</sub>O<sub>4</sub>, respectively). Further, CuO-Co<sub>3</sub>O<sub>4</sub> was efficiently utilized as an electrocatalyst for the selective oxidation of hydrazine (Hyz). CuO-Co<sub>3</sub>O<sub>4</sub> shows a high redox response compared to CuO, Co<sub>3</sub>O<sub>4</sub>, CuCo<sub>2</sub>O<sub>4</sub>, and the physical mixture of CuO and Co<sub>3</sub>O<sub>4</sub> (CuO/Co<sub>3</sub>O<sub>4</sub>). This enhanced performance is attributed to the synergistic interaction between the metal ions caused by their close proximity and the increased exposure of surface active sites. CuO-Co<sub>3</sub>O<sub>4</sub> shows a broad linear range (1–3500 µM), a low detection limit (0.29 µM), and high sensitivity (0.5756 µA µM<sup>-1</sup> cm<sup>-2</sup>) for the Hyz determination. Kinetic parameters, for instance the diffusion coefficient and catalytic rate constant for Hyz oxidation were obtained using chronoamperometry. Additionally, CuO-Co<sub>3</sub>O<sub>4</sub> was effectively utilized to analyze Hyz in real samples with acceptable recovery rates.</div></div>","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"510 ","pages":"Article 145337"},"PeriodicalIF":5.5,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142596624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-09DOI: 10.1016/j.electacta.2024.145330
Zhengqing Pei , Jiawei Wang , Haifeng Wang , Kexin Zheng , Qian Wang , Jiexin Zhou , Dehua Ma , Ju Lu , Fanghai Lu
The study investigated the evolution of LNMO (LiNi0.5Mn1.5O4) morphology and surface orientation as a function of increasing temperature. The results show that at an initial calcination temperature of 750 °C, LNMO exhibits spherical polyhedral with (111), (110), and (100) facets and relatively small particle sizes. In response to increasing temperatures, the particle size increases, the number of crystal facets decreases, and the material ultimately transitions to a typical spinel structure. Notably, the LNMO material calcined at 750 °C demonstrates a high lithium-ion migration rate, retaining 81.24% of its capacity after 500 cycles at a 2 C rate. This exceptional performance is attributed to the exposure of multiple crystal facets, suitable particle size, and the presence of Mn³⁺, which collectively stabilize the crystal structure and provide suitable pathways for Li⁺ transport.
{"title":"Morphological evolution and surface orientation effects of nickel manganese oxide in the preparation of LNMO cathode material","authors":"Zhengqing Pei , Jiawei Wang , Haifeng Wang , Kexin Zheng , Qian Wang , Jiexin Zhou , Dehua Ma , Ju Lu , Fanghai Lu","doi":"10.1016/j.electacta.2024.145330","DOIUrl":"10.1016/j.electacta.2024.145330","url":null,"abstract":"<div><div>The study investigated the evolution of LNMO (LiNi0.5Mn1.5O4) morphology and surface orientation as a function of increasing temperature. The results show that at an initial calcination temperature of 750 °C, LNMO exhibits spherical polyhedral with (111), (110), and (100) facets and relatively small particle sizes. In response to increasing temperatures, the particle size increases, the number of crystal facets decreases, and the material ultimately transitions to a typical spinel structure. Notably, the LNMO material calcined at 750 °C demonstrates a high lithium-ion migration rate, retaining 81.24% of its capacity after 500 cycles at a 2 C rate. This exceptional performance is attributed to the exposure of multiple crystal facets, suitable particle size, and the presence of Mn³⁺, which collectively stabilize the crystal structure and provide suitable pathways for Li⁺ transport.</div></div>","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"509 ","pages":"Article 145330"},"PeriodicalIF":5.5,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142596713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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