Electrochimica Acta最新文献

{"title":"Tailoring the Electronic Conductivity of Coating Layer on the Composite Separator for Li Metal Anode","authors":"Tian-Qi Xiang, Zhi- Yu Hu, Hong Huo, Jian-Jun Zhou, Lin Li","doi":"10.1016/j.electacta.2024.145394","DOIUrl":"https://doi.org/10.1016/j.electacta.2024.145394","url":null,"abstract":"Protection of lithium (Li) metal anodes is essential for the high performance of lithium metal batteries. Although the SnO₂ coating layer on the composite separator can provide protection for the Li metal anode, the effect diminishes over time as Li is plated on the coating surface, which can be attributed to the increased electronic conductivity of the reduced SnO₂ artificial solid electrolyte interfacial layer. Here, poly(vinylidene fluoride) (PVDF) is blended with SnO₂ to form an insulated SnO₂/PVDF hybrid coating layer. The SnO₂/PVDF hybrid coating layer significantly mitigates initial capacity loss and enhances the Coulombic efficiency of Cu||Li batteries. Adjustments to electronic conductivity of coating layer result in the deposition of large grain size Li beneath the hybrid coating layer. The SnO₂/PVDF (=7/3) (S₇P₃) layer can stabilize the freshly deposited Li and improve the cycling performance of the Cu@Li/S₇P₃ electrode. The S₇P₃@PE composite separator can significantly increase the cycle performance of LiFePO₄ (LFP)||Li batteries under low-temperature conditions. Furthermore, the S₇P₃ layer can provide substantial advantages to LFP batteries with limited Li capacity, as well as to lithium-free anodes. Our approach to regulating Li deposition behavior by tailoring the electronic conductivity of the coating layer facilitates the long-term stability of the Li metal anode.","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"18 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142678781","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}

{"title":"Unveiling Manganese Malate as an Electrode Material for Supercapacitors","authors":"Krithika Mani, Thiruvenkatam Subramaniam, Sowmya Ramachandran, S. Devaraj","doi":"10.1016/j.electacta.2024.145395","DOIUrl":"https://doi.org/10.1016/j.electacta.2024.145395","url":null,"abstract":"Supercapacitors are attractive due to their rapid charge storage/release capabilities and long cycle-life. However, their energy density is lower than batteries. The research community is continuously developing new electrode materials with high energy and high power capabilities. In view of this, manganese malate is unveiled as an electrode material for supercapacitor applications. Manganese malate is electrodeposited on a stainless-steel foil (area: 2 cm²) by chronoamperometry at various cell voltages (2/3/4 V). While X-ray diffraction and infrared spectroscopic studies confirm the formation of manganese malate, electron microscopic studies reveal that the morphology of manganese malate deposit is nanoparticulate. Manganese malate electrodeposited at 2 V (MnM2) delivers a specific capacitance of 186 F g^-1 at 1 A g^-1, and stable cycle-life over 10000 cycles in 0.1 M Mg(ClO₄)₂. In addition, a symmetric supercapacitor fabricated using MnM2 delivers a specific energy of 6.25 Wh kg^-1 at a specific power of 250.2 W kg^-1.","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"25 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142678783","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}

{"title":"Electrochemical Synthesis and Carbon Doping of Nanostructured Iron Fluorides from the Selection of Metal Current Collectors in Lithium-Ion Batteries","authors":"D. Álvarez, B. Díaz, B. Guitián, X.R. Nóvoa, A. Pintos, S. Valverde-Pérez","doi":"10.1016/j.electacta.2024.145392","DOIUrl":"https://doi.org/10.1016/j.electacta.2024.145392","url":null,"abstract":"The use of materials that rely on conversion reactions as electrodes in lithium-ion batteries is extensively investigated due to their potential for enhanced capacity compared to traditional electrode materials. Iron fluorides, in particular, present a promising alternative in terms of specific capacity. However, these materials often face challenges related to low intrinsic conductivity. This issue is typically addressed in the literature by doping the active material with carbon particles and reducing the particle size of the active material. This study explores the feasibility of directly integrating conductive carbon from the substrate into the fluoride-based active material during the synthesis process. The synthesis employs a simple anodic method conducted directly on the chosen metallic substrate, which then functions as the current collector in the devices. This approach simplifies the synthesis process, reduces processing time, and eliminates the need for additives and binders at the conventional active material-current collector interface. Two FeF₃ layers were electrochemically synthesized on steel substrates with different carbon contents. These layers were evaluated as cathode-active materials for rechargeable lithium-ion batteries. The influence of carbon on the conductivity of the conversion layer was assessed using Electrochemical Impedance Spectroscopy (EIS) with a model based on conductive porous electrodes. Morphological and thickness analyses of the layers showed a strong correlation between increased pore size and layer thickness and the carbon content in the metallic substrate. The optimal performance was observed with the layer on the substrate with higher carbon content. The electrochemical performance of the active material was further evaluated using electrochemical impedance spectroscopy and galvanostatic tests in pouch cells. The conversion layers derived from carbon steel exhibited reduced resistivity and enhanced specific capacitance and cyclability compared to layers formed on pure iron.","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"1 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142678785","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}

{"title":"One-pot Synthesis of Heteroatom-rich Anthraquinone-based Benzoxazine-linked Porous organic polymers for high performance supercapacitors","authors":"Ahmed F. Saber, Shimaa Abdelnaser, Ahmed F.M. EL-Mahdy, Shiao-Wei Kuo","doi":"10.1016/j.electacta.2024.145397","DOIUrl":"https://doi.org/10.1016/j.electacta.2024.145397","url":null,"abstract":"Recently, the search for efficient and durable electrodes for energy storage has prompted the development of novel porous organic polymers (POPs). Here, we have studied the design, preparation and comprehensive characterization of a novel set of anthraquinone-based benzoxazine-linked POPs as electrode materials for supercapacitors (SCs). The polymers with high yield have been synthesized by direct coupling of various triamines, diphenol and paraformaldehyde. The benzoxazine linkage´s formation and porosity parameters were readily analyzed using FTIR spectra, solid-state ¹³C NMR and N₂ sorption analysis. The benzoxazine backbone provides the POPs with abundant nitrogen and oxygen heteroatoms, making them efficient candidates for storing energy. We observed that the superior benzoxazine-linked polymer exhibited the greatest electrochemical capacitance up to 117.7 F g^‒1 at 1.0 A g^‒1 was the An-TPA POP, which was mainly owing to the most microporous structure, accessible morphology and the largest specific surface area compared to others. In addition, it possessed the highest retention stability after 10,000 charge-discharge cycles (81.55%), as well as lower ohmic resistance (5.38 Ω). Interestingly, a two-electrode system holding the An-TPA POP displayed an excellent electrochemical capacitance of 62 F g⁻¹ at 1.0 A g⁻¹, a greater cycling retention of 95.71% after 5000 GCD cycles at 10 A g⁻¹, as well as a prime energy density of 8.57 W h kg^–1. The results obtained demonstrated a significant tactic for constructing heteroatoms-rich POPs for next-generation SCs, offering improved efficiency and stability.","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"230 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142678732","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}

{"title":"Study on the treatment of carbon black for slurry electrodes of all-iron redox flow batteries","authors":"Nitika Devi, Prabhakar Singh, Amornchai Arpornwichanop, Yong-Song Chen","doi":"10.1016/j.electacta.2024.145393","DOIUrl":"https://doi.org/10.1016/j.electacta.2024.145393","url":null,"abstract":"All-iron redox flow batteries (IRFBs) are considered as potential energy storage devices due to the abundance of iron and durability. During the charging process, metallic iron is formed from Fe²⁺ and may block electrolyte paths in the negative porous electrode, decreasing reaction kinetics. Therefore, a slurry electrode using conductive particles in the electrolyte can be the solution to the problem. To study the effect of carbon black on the performance of slurry electrode, various surface modifications of carbon black are carried out to further enhance electrode performance. The surface morphology, X-ray diffraction, and electrochemical properties are investigated. The performance of the IRFB with various types of carbon black is evaluated at different operating conditions. Both acid and heat treatments of Ketjen black (H-KB) show higher performance than pristine Ketjen black. Thermally treated Ketjen black exhibits voltage efficiency, coulombic efficiency, and energy efficiency of 69%, 95%, and 65%, respectively, at 20 mA cm⁻². The durability of the IRFB using the H-KB slurry electrode shows an EE decreasing rate of around 1% after 100 cycles at 20 mA cm⁻².","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"10 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142678782","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}

{"title":"Effect of variable viscosity and diffusivity as well as Schmidt number on the steady-state hydrodynamic and concentration fields near a rotating hemispherical electrode","authors":"R.M. Lucena, W.G. Santos, J. Pontes, D.J.N.M. Chalhub, N. Mangiavacchi","doi":"10.1016/j.electacta.2024.145356","DOIUrl":"https://doi.org/10.1016/j.electacta.2024.145356","url":null,"abstract":"The focus of this research is on the steady-state boundary layer that forms around a rotating iron hemispherical electrode in an electrochemical cell. Electrode’s material dissolution into the electrolyte solution, accompanied by the current passage through the circuit, generates a concentration boundary layer that is significantly thinner than the hydrodynamic boundary layer, primarily due to high Schmidt numbers typical for practical applications. The change of the solution composition inside this boundary layer leads to an increase in fluid viscosity near the electrode surface and a decrease in the electrolyte’s diffusion coefficient. Prior studies have indicated that radial velocity profiles are similar to those observed in electrolytes with constant viscosity and diffusivity, except for the spatial region near the electrode surface where the concentration boundary layer forms. This difference alters the velocity gradient at the wall, impacting the torque, mass flux, and ultimately the transport-limited current compared to solutions with constant properties. This research further explores the effects of the Schmidt number and the viscosity ratio of the electrolyte (the ratio of the viscosity at the electrode surface to the bulk-solution viscosity), along with the associated diffusivity variations prescribed by the Stokes-Einstein law. The Schmidt number plays an important role in determining the relative thicknesses of the concentration and hydrodynamic boundary layers, affecting the current flow due to electrode dissolution. The set of approximate equations, derived from the boundary layer concept, is solved using the Finite Volume Method in radial and polar-angle coordinates. This approach yields a set of algebraic equations for the discretized profiles of the three velocity components and the concentration at each polar angle. The approximation is valid at high Reynolds numbers for laminar flows, typically encountered in RHSEs, i.e. below the turbulent transition threshold This study is based on previous work where the same set of equations was solved using the power series method (Electrochim. Acta 450 (2023) 142236). The novelty of this study consists in the use of a different method to discretize and to solve the boundary layer equations, which allows for the exploration of a broader range of Schmidt numbers, viscosity ratios, and polar angles than was previously possible. The findings enhance the understanding of steady-state boundary layer dynamics around a rotating iron hemispherical electrode in an electrochemical cell and highlight the significant impact of Schmidt number and viscosity ratio on transport processes within these systems.","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"99 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142673514","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}

{"title":"Operando Identification of Electrocatalyst Layer Generated on Lead Electrode under Oxygen Evolution Reaction","authors":"Naoto Todoroki","doi":"10.1016/j.electacta.2024.145388","DOIUrl":"https://doi.org/10.1016/j.electacta.2024.145388","url":null,"abstract":"Lead (Pb)-based materials are conventionally used as electrodes in various electrochemical systems. However, the chemical state of the surface films working as electrocatalysts has not been clarified in oxygen evolution reaction (OER) environment. In this study, we investigated the chemical state and microstructure of surface films generated on a Pb electrode during OER in a sulfuric acid solution by operando microscopic electrochemical (EC) Raman spectroscopy. The EC-Raman spectra revealed that the Pb-related compounds and crystal structure of the surface films depend on the applied potential and analysis point. Notably, at the main analysis point, a sharp band of β-PbO₂ was detected as the main phase in the OER potential region and its intensity increased with increase in the applied potential. On the other hand, at another analysis point, the band for β-PbO₂ did not appear in the same potential region. Instead, α-PbO₂ and β-PbO, which have a lower electronic conductivity than β-PbO₂, were detected, and the band intensities were almost unchanged by increasing the potential up to 1.9 V. The results indicate that the local environment significantly affects the chemical states of EC-generated surface films on a Pb electrode and β-PbO₂ acts as the main OER active site.","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"251 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142673512","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}

{"title":"An updated Pitting Resistance Equivalent Number by proportional hazard survival models of reported pitting potentials","authors":"Dimitri Soccol","doi":"10.1016/j.electacta.2024.145355","DOIUrl":"https://doi.org/10.1016/j.electacta.2024.145355","url":null,"abstract":"The Pitting Resistance Equivalent Number (PREN) is widely applied to assess pitting corrosion resistance of stainless steel, despite containing only a few compositional elements. A reformulation of the PREN was established by statistical analysis of a public pitting potential data set. Statistical pitfalls were identified and properly addressed by multiple imputation and principles from survival analysis, such as censoring and mixed effects. This statistical framework allowed for simultaneous inclusion of surface pretreatment and test environment next to alloy composition in an updated PREN. Comparison of Weibull and non-parametric baseline hazard functions indicate that pitting potentials might not be Weibull distributed.","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"177 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142673494","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}

{"title":"Preparation and Carbon Nanotube Modification of High Voltage LiNi0.5Mn1.5O4 Cathode Materials","authors":"Ju Lu, Jiawei Wang, Haifeng Wang, Hao Wang, Fanghai Lu","doi":"10.1016/j.electacta.2024.145386","DOIUrl":"https://doi.org/10.1016/j.electacta.2024.145386","url":null,"abstract":"In this study, the nickel-manganese binary cathode material was synthesized using a high-temperature solid-state roasting method. The effects of roasting temperature and roasting time on the electrochemical performance of the cathode material was investigated. The research demonstrated that under conditions of 850°C for 12 hours, the synthesized LNMO exhibited an Fd-3m space group structure characterized. The initial discharge-specific capacity reached 135 mAh·g⁻¹ at a rate of 0.2C, while the capacity retention rate was 91.8% after 100 cycles. Following the modification with carbon nanotubes, exhibited an initial discharge capacity of 140 mAh·g⁻¹ at a rate of 0.2C, maintaining a capacity retention rate of 92.9% after 100 cycles. Carbon nanotube modification was implemented to address the poor conductivity and unstable electrochemical performance of LNMO when utilizing acetylene black as a conductive agent. This finding suggests that the unique three-dimensional conductive network formed by carbon nanotube offers superior modification effects compared to acetylene black, while the reduced quantity of conductive agent used also contributes to cost savings.","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"99 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142673492","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}

{"title":"Electrochemical CO2 Reduction by Heterogeneous Catalysts of 2D Metal-Organic Frameworks Comprising Metal-Coordinated Porphyrins","authors":"Kuang-Yen Chiu, Chen-Wei Chan, Hsin-Tsung Chen","doi":"10.1016/j.electacta.2024.145389","DOIUrl":"https://doi.org/10.1016/j.electacta.2024.145389","url":null,"abstract":"In this study, we employed first-principles computations to design two-dimensional (2D) metal organic framework (MOF) electrocatalysts with metal-porphyrin nanosheets (TM-TCPP-MOF), for CO₂ electroreduction. We investigated 3d-transition metal doping on the porphyrin units to screen for efficient catalysts. Structural stability, including thermodynamic and electrochemical stability, was evaluated through binding energy, cohesive energy, formation energy, and dissolution potential analyses. Our results show that TM-TCPP-MOF catalysts are both thermodynamically and electrochemically stable, and the predicted Gibbs free energy profiles indicate HCOOH and CO as the most likely products. The stability of *COOH on Fe-, Co-, Ni-, and Cu-TCPP-MOF leads to CO formation, while *OCHO stabilization on Sc-, Ti-, V-, Cr-, and Mn-TCPP-MOF favors HCOOH production. The competitive hydrogen evolution reaction (HER) was evaluated to study the selectivity. Cr-TCPP-MOF and Co-TCPP-MOF exhibit superior selectivity and activity for CO₂ electroreduction.","PeriodicalId":305,"journal":{"name":"Electrochimica Acta","volume":"14 1","pages":""},"PeriodicalIF":6.6,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142673493","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}