ACS electrochemistry最新文献_第3页

Operando Microscopy of Photosynthetic Microbial Biohybrids Using Fluorescent Chemical Probes. 使用荧光化学探针的光合微生物杂交体的Operando显微镜。

ACS electrochemistry Pub Date : 2026-03-04 eCollection Date: 2026-04-02 DOI: 10.1021/acselectrochem.5c00517

Leanne A Milburn, Evan I Wroe, Mairi Eyres, Joshua M Lawrence, Jenny Z Zhang

{"title":"Operando Microscopy of Photosynthetic Microbial Biohybrids Using Fluorescent Chemical Probes.","authors":"Leanne A Milburn, Evan I Wroe, Mairi Eyres, Joshua M Lawrence, Jenny Z Zhang","doi":"10.1021/acselectrochem.5c00517","DOIUrl":"10.1021/acselectrochem.5c00517","url":null,"abstract":"Photosynthetic biohybrids, often in the form of biophotoelectrochemical devices, aim to achieve solar-to-chemical conversion by pairing biotic and abiotic materials to leverage the beneficial attributes of both. Numerous works have highlighted the importance of a well-tuned bio-electrode interface for high biophotoelectrode performance. However, the dynamics of these interfaces in photosynthetic biohybrids are poorly understood, necessitating the development of new tools to disentangle the various (bio)-chemical processes occurring simultaneously. In this work, we construct an operando confocal microscopy platform to deeply analyze the dynamics in biofilm morphology, interfacial pH, and membrane potential. These methods assert that light availability is the main driver of microenvironment formation at the interface of a model Synechocystis-indium tin oxide bioelectrode. The potential of the electrode only induces a substantial impact outside of the potential range -0.32 to +0.48 V vs. Ag/AgCl at typical current densities. This toolkit provides a foundation for further elucidating interfacial dynamics and rational design of these systems and can be expanded to other bioelectrochemical constructs.","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"2 4","pages":"964-973"},"PeriodicalIF":0.0,"publicationDate":"2026-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13051432/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147635553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Comparing Tandem Cell Designs for Electrochemical CO₂ Reduction to Ethylene. 电化学CO2还原制乙烯串联电池设计的比较。

ACS electrochemistry Pub Date : 2026-02-25 eCollection Date: 2026-04-02 DOI: 10.1021/acselectrochem.5c00446

Tobias A Kistler, Mohammed H Abouremeleh, Ryan A Rivera, Erik E Jackson, Yesol Kim, Finn Babbe, Peter Agbo

{"title":"Comparing Tandem Cell Designs for Electrochemical CO2 Reduction to Ethylene.","authors":"Tobias A Kistler, Mohammed H Abouremeleh, Ryan A Rivera, Erik E Jackson, Yesol Kim, Finn Babbe, Peter Agbo","doi":"10.1021/acselectrochem.5c00446","DOIUrl":"10.1021/acselectrochem.5c00446","url":null,"abstract":"Electrochemical carbon dioxide reduction (CO2R) is a promising approach for the decentralized production of fuels such as ethylene (C2H4). However, the use of Cu, the most efficient metal CO2R catalyst for the generation of C2H4 known to date, generally yields a product stream with poor selectivity. In an effort to increase selectivity, the reaction from CO2 to C2H4 can be broken down into two steps using tandem CO2R electrolyzers: formation of CO from CO2 and subsequent reduction of CO to C2H4. Here, we present two novel tandem electrolyzer architectures that closely integrate two cathodes, one for CO generation and one for conversion to C2H4, while still enabling independent electrical control of the cathodic surfaces. Cathode segmentation in each of these designs also permits the controlled sequencing of mass flow of chemical intermediates in the order of Au to Cu cathode catalysts, in contrast to earlier work relying on uncontrolled, passive diffusion to facilitate the flow of chemical intermediates between catalysts. When comparing the performance of the newly developed electrolyzer cell designs with a dual electrolyzer system, we found that the dual electrolyzer system yields the highest C2H4 faradaic efficiencies (FEs) of 31% and C2H4 concentrations (∼8 mol %). However, a single Cu-containing electrolyzer outperformed all three tandem systems in terms of C2H4 FE (34%). Our findings, enabled by independent control of the two tandem cathode surfaces, indicate that tandem CO2R systems need to be evaluated carefully by testing them at various relevant current densities.","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"2 4","pages":"931-938"},"PeriodicalIF":0.0,"publicationDate":"2026-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13052376/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147635511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Sustainable Electrosynthesis of Propylamines through Nitrogen Reduction on a MoS₂ Catalyst. 二硫化钼催化氮还原可持续电合成丙胺。

ACS electrochemistry Pub Date : 2026-02-12 eCollection Date: 2026-03-05 DOI: 10.1021/acselectrochem.5c00490

Caio V S Almeida, Ana B Cardile, Lucia H Mascaro, Frank Marken

{"title":"Sustainable Electrosynthesis of Propylamines through Nitrogen Reduction on a MoS2 Catalyst.","authors":"Caio V S Almeida, Ana B Cardile, Lucia H Mascaro, Frank Marken","doi":"10.1021/acselectrochem.5c00490","DOIUrl":"10.1021/acselectrochem.5c00490","url":null,"abstract":"The electrocatalytic utilization of nitrogen compounds for C-N coupling chemistry is a promising research area with significant potential to become a sustainable method for producing organonitrogen molecules. The most commonly employed C-N coupling reaction is reductive amination. In this study, we demonstrate an alternative electrochemical reductive amination reaction using N2 gas as the nitrogen source, which enables the production of isopropylamine and diisopropylamine in a single process. For instance, these reactions occur at amorphous MoS2-coated carbon paper electrodes. This opens the doors to complex molecule electrosynthesis directly from the gas feed. The effects of the acetone concentration and applied potential on reaction yields are investigated. Direct gas feed is demonstrated as a sustainable electro-organic synthetic technology for organic amines. There is an increase in the production of C3H9N and C6H15N with increasing acetone concentration. For 0.4 M acetone under N2 (at pH 7.0), isopropylamine and diisopropylamine yield rates are 3.1 and 6.7 μg h-1 mg-1, respectively, at -0.85 V SCEsat. KCl. The highest faradaic efficiency is obtained at -0.75 V SCEsat. KCl for C3H9N (0.46%) and C6H15N (2.0%). At more negative potentials, there is a decrease in the production of both amines mainly due to the enhanced/competing HER. In all cases, diisopropylamine is the main organic product. This work provides a new and attractive strategy for organic amine synthesis via one-step electrochemical nitrogen reduction.","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"2 3","pages":"705-714"},"PeriodicalIF":0.0,"publicationDate":"2026-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12969268/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147438960","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Aptamer-Based Scanning Electrochemical Microscopy for Specific and Localized Detection of Analyte Concentration. 基于适体体的扫描电化学显微镜用于分析物浓度的特异和局部检测。

ACS electrochemistry Pub Date : 2026-02-05 Epub Date: 2025-12-23 DOI: 10.1021/acselectrochem.5c00341

Debashis Sen, Robert A Lazenby

{"title":"Aptamer-Based Scanning Electrochemical Microscopy for Specific and Localized Detection of Analyte Concentration.","authors":"Debashis Sen, Robert A Lazenby","doi":"10.1021/acselectrochem.5c00341","DOIUrl":"10.1021/acselectrochem.5c00341","url":null,"abstract":"Scanning electrochemical microscopy (SECM) is an excellent electroanalytical technique for localized detection of analytes, providing high spatial resolution through precise positioning and controlled scanning of an electrode over a sample substrate. However, the applicability of this method is largely limited to ox active analytes, with biosensor-based detection strategies remaining scarce other than a few examples using enzymes as the bioreceptor. In this study, we introduce aptamer-based (AB)-SECM, in which electrochemical aptamer-based biosensors are used as the imaging probe, and this new imaging mode is demonstrated for the localized detection of dopamine and adenosine triphosphate (ATP) released from a model micropore system. This study describes the fabrication and characterization of the model micropore system, that is imaged using the amperometric feedback mode of SECM. This substrate is then imaged using AB-SECM, using an imaging probe (electrode 25 - 35 μm in diameter) with immobilized target specific aptamers on surface. The probe was positioned at a known distance from the micropore surface by recording an amperometric approach curve, in which the oxidation of ferrocyanide through the sensor monolayer produced a negative feedback distance dependent response. For constant height imaging with AB-SECM, the probe was moved and a square wave voltammogram (SWV) was recorded at each pixel. The obtained AB-SECM images showed a higher concentration of target analyte above the opening of the micropore, with decreasing concentration further from the pore. These results demonstrate the capability of AB-SECM for positioning of the probe at a known distance from a surface, and for localized detection, which we envisage could be further adapted for performing chemical analysis at the single cell level.","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"2 2","pages":"274-285"},"PeriodicalIF":0.0,"publicationDate":"2026-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13268583/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148267824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Tackling Faradaic Imbalance in Redox Flow Batteries by the Use of a Solid Reducing Agent. 利用固体还原剂解决氧化还原液流电池中的法拉第不平衡。

ACS electrochemistry Pub Date : 2026-02-04 eCollection Date: 2026-03-05 DOI: 10.1021/acselectrochem.5c00520

Gimena Marin-Tajadura, Ismael Suárez-Esteban, Ruben Rubio-Presa, Virginia Ruiz, Edgar Ventosa

{"title":"Tackling Faradaic Imbalance in Redox Flow Batteries by the Use of a Solid Reducing Agent.","authors":"Gimena Marin-Tajadura, Ismael Suárez-Esteban, Ruben Rubio-Presa, Virginia Ruiz, Edgar Ventosa","doi":"10.1021/acselectrochem.5c00520","DOIUrl":"10.1021/acselectrochem.5c00520","url":null,"abstract":"Redox flow batteries (RFBs) represent a promising technology for large-scale energy storage. However, they suffer from capacity fading due to various factors, including desynchronization in the state of charge of the anolyte and catholyte, often caused by irreversible electrochemical side reactions. This study proposes a novel strategy to mitigate and reverse the effects of the faradaic imbalance by, for the first time to the best of our knowledge, introducing a solid reducing agent, LiFePO4 (LFP), in the catholyte compartment. The use of a heterogeneous reaction facilitates the removal of the reaction product, in contrast to homogeneous reducing agents. The strategy is implemented in a battery comprising K4Fe-(CN)6 as the catholyte and a viologen, 1,1'-bis-(3-sulfonatopropyl)-4,4'-bipyridinium (BSPV), as the anolyte in 1M KCl supporting electrolyte at neutral pH. The presence of trace oxygen in the anolyte leads to the accumulation of K3Fe-(CN)6 in the catholyte, resulting in a faradaic imbalanceused here as a case study. Introducing LFP pellets into the catholyte chemically reduces the accumulated K3Fe-(CN)6 back to K4Fe-(CN)6 via a spontaneous redox process, accompanied by the oxidation of LFP to FePO4, as confirmed by XRD analysis. Implementation of this method in a flow cell with a capacity-limiting catholyte results in a significant recovery of the lost capacity, which is attributed to the reduction of accumulated K3Fe-(CN)6 by the LFP pellets. This study presents a promising approach to addressing the faradaic imbalance in RFBs, potentially leading to improved performance and extended operational lifetime of these systems.","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"2 3","pages":"745-751"},"PeriodicalIF":0.0,"publicationDate":"2026-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12969641/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147438977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Oxide Growth and Place-Exchange on Au(111) in Alkaline Electrolyte. Au（111）在碱性电解液中的氧化物生长和位置交换。

ACS electrochemistry Pub Date : 2026-02-03 eCollection Date: 2026-03-05 DOI: 10.1021/acselectrochem.5c00505

Toni Moser, Francesc Valls Mascaró, Andrea Auer, Julia Kunze-Liebhäuser

{"title":"Oxide Growth and Place-Exchange on Au(111) in Alkaline Electrolyte.","authors":"Toni Moser, Francesc Valls Mascaró, Andrea Auer, Julia Kunze-Liebhäuser","doi":"10.1021/acselectrochem.5c00505","DOIUrl":"10.1021/acselectrochem.5c00505","url":null,"abstract":"Understanding the oxidation processes of noble metals is essential for the elaborate design of functional and stable materials for electrochemical applications, where electrocatalysis is currently central due to the need for efficient direct energy conversion devices. Single crystalline gold (Au(111)) is an important noble metal standard, as it has high relevance as an electrocatalyst material and is best suited for the study of fundamental surface and interface processes due to its high nobility and the model applicability of the processes at its electrified solid/liquid interface. Under electrochemical conditions, Au(111) oxidation proceeds via a place-exchange mechanism, in which surface Au atoms exchange positions with adsorbed oxygen species. While this process is well studied in acidic media, where it results in the nucleation and growth of adatom and vacancy islands alongside partial dissolution, its behavior in alkaline media remains less explored. Here, we investigate the oxidation of Au(111) in 0.1 M NaOH, providing new insights into the oxidation process and associated surface restructuring mechanisms. Using electrochemical scanning tunneling microscopy, we directly observe the growth of a surface oxide layer across the Au(111) terraces, which reveals the slow, kinetically limited dynamics of the place-exchange process. Once this place-exchange process has occurred, the pristine surface structure is not restored upon electrochemical reduction within experimental time scales, as vacancy islands form and persist. These findings are crucial for developing strategies to mitigate catalyst degradation and enhance the stability of Au-based materials in electrochemical applications.","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"2 3","pages":"726-734"},"PeriodicalIF":0.0,"publicationDate":"2026-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12969257/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147438858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

In Situ Monitoring of Hypochlorite Decay under Radiation Using Differential Pulse Voltammetry. 差分脉冲伏安法监测辐射下次氯酸盐衰变。

ACS electrochemistry Pub Date : 2026-02-02 eCollection Date: 2026-03-05 DOI: 10.1021/acselectrochem.5c00338

Taras Skotar, Emmanuel Mena-Morcillo, Reza Moshrefi, Scott Briggs, Peter George Keech, Mehran Behazin, Fraser King, Samantha Michelle Gateman

{"title":"In Situ Monitoring of Hypochlorite Decay under Radiation Using Differential Pulse Voltammetry.","authors":"Taras Skotar, Emmanuel Mena-Morcillo, Reza Moshrefi, Scott Briggs, Peter George Keech, Mehran Behazin, Fraser King, Samantha Michelle Gateman","doi":"10.1021/acselectrochem.5c00338","DOIUrl":"10.1021/acselectrochem.5c00338","url":null,"abstract":"Understanding how concentrations of corrosive oxidants evolve under γ-radiation is essential for assessing long-term material performance in nuclear environments. This work integrates in situ differential pulse voltammetry (DPV) with finite-element kinetic modeling to track and interpret the decay of hypochlorite (OCl-) in aerated 0.1 M NaCl at pH ∼9.9 under a dose rate of 725 Gy h-1. Using a three-electrode setup inside a 60Co γ-cell, OCl- was quantified from calibration curves, where concentrations were validated ex situ by UV-vis spectroscopy. For an initial OCl- added concentration of 10 mM, both methods showed a decrease to ∼1 mM after 24 h. Kinetic analysis based on a radiolysis/halogen reaction scheme indicates that HOCl consumption is dominated by OH• abstraction (∼71%), with a secondary contribution from O2 •- reduction (∼22%) and a minor Cl--mediated pathway (∼7%); contributions from e- and H• are negligible at the steady state. The added HOCl drives a pronounced rise in OCl• that feeds back to lower the steady-state OH• level and modulates H2O2 formation. From these kinetics, it is estimated that g HOCl ≈ -0.53 μmol J-1. Beyond validating DPV as an in situ radiation electroanalytical method, the combined measurements and modeling provide a mechanistic basis for OCl- transformation in saline waters, establishing a general radiation-electrochemistry platform for time-resolved detection of radiolysis products relevant to nuclear-waste containment.","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"2 3","pages":"620-627"},"PeriodicalIF":0.0,"publicationDate":"2026-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12969269/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147438887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Expanding the Toolbox of Multi-Material Three-Dimensional-Printed Electrochemical Flow Cells Fabricated in a Single Step: Impinging Jet, Mixing and Dilution, and Dual-Electrode Generator-Collector Electrochemical Cells. 扩展多材料三维印刷电化学流动电池的工具箱在一个步骤中制造：撞击喷射，混合和稀释，和双电极发生器-收集器电化学电池。

ACS electrochemistry Pub Date : 2026-01-30 eCollection Date: 2026-03-05 DOI: 10.1021/acselectrochem.5c00444

Kayla M Mancini, Enock G Arthur, Cameron Darvish, Edgar M Manriquez, Inara Trongone, Glen D O'Neil

{"title":"Expanding the Toolbox of Multi-Material Three-Dimensional-Printed Electrochemical Flow Cells Fabricated in a Single Step: Impinging Jet, Mixing and Dilution, and Dual-Electrode Generator-Collector Electrochemical Cells.","authors":"Kayla M Mancini, Enock G Arthur, Cameron Darvish, Edgar M Manriquez, Inara Trongone, Glen D O'Neil","doi":"10.1021/acselectrochem.5c00444","DOIUrl":"10.1021/acselectrochem.5c00444","url":null,"abstract":"Hydrodynamic electrochemical cells have broad utility in sensing, electrocatalysis, mechanistic studies, and electroanalysis. Here, we report on the expansion of hydrodynamic electrochemical devices that can be fabricated using 3D printing beyond channel flow electrodes to include impinging jet electrodes, a dilution/mixing circuit for in-channel detection of electroactive species, and dual-electrode generator-collector cells. These examples highlight the ability of 3D printing to produce intricate structures with internal voids, enhance analytical functionality, and enable sophisticated operations such as fluid mixing and generation-collection in simple, monolithic devices that do not require alignment, clamping, or assembly. To promote adoption by the wider electrochemical community, we provide printable .stl files as part of the manuscript. Device performance was evaluated in both stagnant and flowing solutions of ferrocene methanol, an outer-sphere redox mediator suitable for characterizing the transport characteristics and electrochemical performance of the devices. All devices exhibited responses consistent with Levich behavior for their respective geometries. The mixing circuit achieved 100-fold dilutions with results in excellent agreement with solutions prepared using volumetric glassware, while the generator-collector cell demonstrated high collection efficiencies under optimized conditions. These results establish 3D printing as a versatile, accessible approach for fabricating hydrodynamic electrochemical devices with advanced capabilities and pave the way for customizable, high-performance devices suitable for electroanalysis, electrocatalysis, and sensing applications.","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"2 3","pages":"651-660"},"PeriodicalIF":0.0,"publicationDate":"2026-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12969262/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147438894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Origin of the Constant Phase Element Behavior of Pt(111) Near the Potential of Zero Charge. Pt（111）在零电荷电位附近恒相元行为的起源。

ACS electrochemistry Pub Date : 2026-01-29 eCollection Date: 2026-03-05 DOI: 10.1021/acselectrochem.5c00481

Katherine J Levey, Nicci L Fröhlich, Steffen Hardt, Lucas B T de Kam, Marc T M Koper

{"title":"The Origin of the Constant Phase Element Behavior of Pt(111) Near the Potential of Zero Charge.","authors":"Katherine J Levey, Nicci L Fröhlich, Steffen Hardt, Lucas B T de Kam, Marc T M Koper","doi":"10.1021/acselectrochem.5c00481","DOIUrl":"10.1021/acselectrochem.5c00481","url":null,"abstract":"Despite the Pt(111)/HClO4 interface being a model system in electrochemistry, its electric double-layer (EDL) behavior deviates significantly from classical models. In the double-layer region (0.40-0.60 VRHE), electrochemical impedance spectroscopy reveals non-ideal capacitance behavior, which is best described by a constant phase element rather than an ideal capacitor. The extent of non-ideal capacitive behavior can be quantified using the CPE exponent (α), in which we observe two distinct regimes: a decrease at potentials away from the potential of zero charge (PZC), and a pronounced minimum at the PZC itself. To interpret these findings, we combine experimental data with two-dimensional numerical simulations solving the coupled Poisson-Nernst-Planck equations. Our findings show that non-ideal capacitive behavior at potentials away from the PZC arises from finite mass transport within the EDL and an inhomogeneous current/potential distribution across the disc electrode, which results from the cell and electrode geometry. The anomalous α minimum at potentials closer to the PZC is the result of a second potential-dependent variable, which we propose to be electrowetting that alters the geometry of the wetted edge of the disk electrode in the hanging meniscus configuration and therefore the corresponding local electric field. These results highlight the critical roles of cell geometry, edge effects, and electrolyte concentration in modulating frequency dispersion. This work provides new physical insights into capacitance dispersion at well-defined interfaces and lays the foundation for more accurate models of electrochemical systems involving confined geometries and interfacial heterogeneity.","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"2 3","pages":"693-704"},"PeriodicalIF":0.0,"publicationDate":"2026-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12969267/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147438951","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Absolute Calibration for Cyclic Voltammetry from the Solution-Phase Ionisation of Ferrocene. 二茂铁溶液电离循环伏安法的绝对校准。

ACS electrochemistry Pub Date : 2026-01-20 eCollection Date: 2026-02-05 DOI: 10.1021/acselectrochem.5c00382

Tomi K Baikie, Jonathon R Harwell, Iain D Baikie, Eli Zysman-Colman, Ifor D W Samuel, Graham A Turnbull

{"title":"Absolute Calibration for Cyclic Voltammetry from the Solution-Phase Ionisation of Ferrocene.","authors":"Tomi K Baikie, Jonathon R Harwell, Iain D Baikie, Eli Zysman-Colman, Ifor D W Samuel, Graham A Turnbull","doi":"10.1021/acselectrochem.5c00382","DOIUrl":"10.1021/acselectrochem.5c00382","url":null,"abstract":"Accurate determination of the energy levels of materials is crucial to many fields of science and technology, including electronics, catalysis, and energy generation and storage. The frontier molecular orbital levels of molecules are commonly inferred from their oxidation and reduction potentials measured in solution using voltametric techniques, which are reported versus a standard, typically an internal one such as a ferrocenium/ferrocene (Fc+/Fc) redox couple. At present, however, multiple reference electrode scales are used across the literature, leading to discrepancies of up to 0.3 eV. Here, we report an absolute energy level measurement for (Fc+/Fc) in acetonitrile solution. Specifically, we determined the adiabatic ionisation energy of ferrocene in acetonitrile solution to be 4.94 ± 0.05 eV using ambient pressure photoemission spectroscopy. By comparing the energy-dependence of photoemission from different solution concentrations with a model for photoemission from solution, we confirm that we measure the adiabatic ionisation energy and that liquid surface barrier effects are minimal. This value is consistent with one of several conflicting reference values used in the literature. The result therefore provides a benchmark value for the Fc+/Fc internal reference, widely used for the conversion of voltammetry data to the absolute energy scale.","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"2 2","pages":"297-304"},"PeriodicalIF":0.0,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12884449/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146159825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0