ACS electrochemistry最新文献

{"title":"Water-Assisted Electrosynthesis of a Lithium-Aluminum Intermetallic from a Lithium Chloride-Ionic Liquid Melt.","authors":"Fabrizio Bernini, Giovanni Bertoni, Adele Mucci, Andrea Marchetti, Daniele Malferrari, Gian Carlo Gazzadi, Marco Ricci, Sergio Marras, Remo Proietti Zaccaria, Enzo Rotunno, Alessio Nicolini, Nassima Yamini, Andrea Cornia, Marco Borsari, Andrea Paolella","doi":"10.1021/acselectrochem.4c00134","DOIUrl":"https://doi.org/10.1021/acselectrochem.4c00134","url":null,"abstract":"<p><p>Although water is considered detrimental for Li-ion battery technology, a 1% w/w amount of water in a melt of LiCl in ionic liquid 1-butyl-3-methylimidazolium chloride promotes the reduction of lithium into a LiAl intermetallic along with water oxidation to O₂ gas. The electrodeposition of an intermetallic layer of several micrometers thickness is demonstrated by combining complementary techniques, such as galvanostatics, X-ray diffraction, electron energy-loss spectroscopy, mass spectrometry, and ¹H nuclear magnetic resonance. The concentration of water in the ionic liquid is found to be a critical feature, as no Li is deposited when ionic liquid is dried. Our findings highlight an innovative and simple method to produce a LiAl intermetallic by using water and lithium chloride as chemical reagents.</p>","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"1 5","pages":"599-606"},"PeriodicalIF":0.0,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12051454/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144061475","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}

{"title":"Electrochemical Flow Reactors: Mass Transport, iR Drop, and Membrane-Free Performance with In-Line Analysis.","authors":"W J Niels Klement, Elia Savino, Sarah Rooijmans, Patty P M F A Mulder, N Scott Lynn, Wesley R Browne, Elisabeth Verpoorte","doi":"10.1021/acselectrochem.4c00167","DOIUrl":"10.1021/acselectrochem.4c00167","url":null,"abstract":"<p><p>Continuous flow reactors are promising for electrochemical conversions, in large part due to the potentially rapid refreshment of reagents over the electrode surface. Microfluidic reactors enable a high degree of control over the fluid flow. Diffusion to and from the electrode and electrode area determine the efficiency of electrochemical conversion. The effective electrode area is limited by the loss in electrode potential due to iR drop, and further electrode length (and hence area) is limited due to ineffective mass transport to and from the electrode. Here, we report on a microfluidic electrochemical device with large (long) area electrodes running in parallel, which both minimizes the iR drop and ensures a constant electrode potential along the whole length of the electrodes. The electrodes are separated by laminar flow in the channels, instead of by a membrane, thereby reducing cell resistance. Herringbone grooves are used to increase mass transport rates by inducing transverse flow. We confirm fluid flow behavior in the devices using computational fluid dynamics (CFD) and verify the results experimentally using in-line and off-line UV/vis absorption and resonance Raman spectroscopy. We anticipate that this approach will aid future development of electrochemical flow reactors, enabling larger area-electrodes and realizing greater efficiencies.</p>","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"1 4","pages":"504-515"},"PeriodicalIF":0.0,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11973871/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143813314","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}

{"title":"Same FeN4 Active Site, Different Activity: How Redox Peaks Control Oxygen Reduction on Fe Macrocycles.","authors":"Silvia Favero, Ruixuan Chen, Joyce Cheung, Luke Higgins, Hui Luo, Mengnan Wang, Jesus Barrio, Maria Magdalena Titirici, Alexander Bagger, Ifan E L Stephens","doi":"10.1021/acselectrochem.4c00146","DOIUrl":"https://doi.org/10.1021/acselectrochem.4c00146","url":null,"abstract":"<p><p>Macrocycles show high activity for the electrochemical reduction of oxygen in alkaline media. However, even macrocycles with the same metal centers and MN4 active site can vary significantly in activity and selectivity, and to this date, a quantitative insight into the cause of these staggering differences has not been unambiguously reached. These macrocycles form a fundamental platform, similarly to platinum alloys for metal ORR catalyst, to unravel fundamental properties of FeNx catalysts. In this manuscript, we present a systematic study of several macrocycles, with varying active site motif and ligands, using electrochemical techniques, <i>operando</i> spectroscopy, and density functional theory (DFT) simulations. Our study demonstrates the existence of two families of Fe macrocycles for oxygen reduction in alkaline electrolytes: (i) weak *OH binding macrocycles with one peak in the voltammogram and high peroxide selectivity and (ii) macrocycles with close to optimal *OH binding, which exhibit two voltametric peaks and almost no peroxide production. Here, we also propose three mechanisms that would explain our experimental findings. Understanding what differentiates these two families could shed light on how to optimize the activity of pyrolyzed FeNx catalysts.</p>","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"1 5","pages":"617-632"},"PeriodicalIF":0.0,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12051206/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144054676","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}

{"title":"In Situ Characterization of the Oxidation Behavior of Carbonate-Based Electrolytes for Lithium-Ion Batteries by Scanning Electrochemical Microscopy.","authors":"Rong He, Liam McDonough, Liam Seitz, Wenhan Ou, Samuel D Marks, Rafael Ferreira de Menezes, Elizabeth Allan-Cole, Hongmei Luo, Michael F Toney, Kayla G Sprenger, Meng Zhou, Robert C Tenent","doi":"10.1021/acselectrochem.4c00106","DOIUrl":"10.1021/acselectrochem.4c00106","url":null,"abstract":"<p><p>Lithium-ion batteries (LIBs) have been widely employed as energy storage devices in portable electronics and electric vehicles. Many processes occurring at the electrode/electrolyte interphases lead to performance degradation over time and yet remain poorly understood. We demonstrate new methods based on scanning electrochemical microscopy (SECM) to characterize LIB electrolyte oxidation, which is a key process occurring at the cathode/electrolyte interphase. Our technique leverages a combination of feedback mode and generation/collection mode SECM to provide an electrochemical reversal technique like commonly used cyclic voltammetry or rotating-ring disk electrode methods but one potentially more easily applicable at shorter time scales. We use our method to probe the oxidation of LIB electrolyte components at nonintercalating electrodes including Pt and glassy carbon. We study the oxidation of a common commercially used electrolyte, 1.2 M LiPF₆ 30% ethylene carbonate and 70% ethyl methyl carbonate electrolyte (LP58), as well as formulations using only the individual carbonates. Our results indicate that all electrolyte formulations characterized oxidize through multiple processes that are detected at distinct voltages. Some processes generate soluble and reducible products that are detected by the SECM tip electrode and may be consistent with deprotonation of carbonate solvents. However, several other oxidation processes do not appear to generate soluble and reducible species and may be connected to the formation of either nonelectroactive products or of processes only occurring on the substrate electrode surface. This work provides information about the electrochemical oxidation of commonly used carbonate electrolytes for comparison to studies involving potentially more complex processes in the presence of LIB cathode materials.</p>","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"1 4","pages":"494-503"},"PeriodicalIF":0.0,"publicationDate":"2024-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11973861/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143813316","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}

{"title":"Beyond Conventional Organic Electrosynthesis: The Role of Fluorinated Solvents.","authors":"Xavier Marset, Salvador Montilla-Verdú, Elio Rico, Néstor Guijarro","doi":"10.1021/acselectrochem.4c00129","DOIUrl":"10.1021/acselectrochem.4c00129","url":null,"abstract":"<p><p>Organic electrosynthesis has emerged as a unique platform for chemical manufacturing owing to not only the use of electricity as a green reagent but also, especially, to its distinct reactivity. While conventional solvents are sought to remain inert and solely provide a liquid environment for the electrochemical process to occur, fluorinated alcohol solvents have been shown to redefine this concept. In fact, the singular properties of these solvents allow them to actively interact with the substrates and reaction intermediates driving dramatic changes in the chemo- and regioselectivity as well as on the reaction yields. Given the rapid permeation of these solvents in the burgeoning field of electro-organic synthesis, this mini-review strives to provide a concise but up-to-date critical revision for the growing community of scientists working at the interface of synthetic chemistry and electrochemistry. Here, the main electrosynthetic transformations where they have been exploited besides their key role in activating certain reaction pathways will be highlighted. Finally, a forward-looking perspective on the more practical evolution and implementation of these systems will be discussed.</p>","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"1 1","pages":"3-19"},"PeriodicalIF":0.0,"publicationDate":"2024-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12312091/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144777634","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}

{"title":"Role of the Ionomer in Supporting Electrolyte-Fed Anion Exchange Membrane Water Electrolyzers.","authors":"Emily K Volk, Arielle L Clauser, Melissa E Kreider, Diego D Soetrisno, Sunilkumar Khandavalli, Joshua D Sugar, Stephanie Kwon, Shaun M Alia","doi":"10.1021/acselectrochem.4c00061","DOIUrl":"10.1021/acselectrochem.4c00061","url":null,"abstract":"<p><p>While anion exchange membrane water electrolyzers (AEMWEs) have achieved significant performance advances in recent decades, overpotentials remain high relative to their proton exchange membrane water electrolyzer (PEMWE) counterparts, requiring AEMWE-specific catalyst layer design strategies to further advance this technology. In this work, the role of the ionomer in catalyst layer structure and quality, catalyst layer stability, and ion conduction for supporting electrolyte-fed AEMWEs is assessed for catalyst layers composed of NiFe₂O₄ and PiperION TP85 from Versogen at variable ionomer contents (0-30 wt %) for tests up to 200 h. The results reveal that, for supporting electrolyte-fed AEM devices, the ionomer is not required for ion conduction through the catalyst layer. Instead, the ionomer is found to play a critical role in catalyst layer structure and stability, where intermediate ionomer contents lead to the lowest overpotentials, highest effective surface areas, and lowest catalyst layer resistances. Catalyst layer stability is found to be a function of both catalyst adhesion and ionomer loss. These results show that an ionomer may be selected which is not of the same chemistry as the anion exchange membrane, mitigating ionomer stability concerns throughout the catalyst layer and offering a pathway towards highly active and stable AEMWEs.</p>","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"1 2","pages":"239-248"},"PeriodicalIF":0.0,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11808641/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143401165","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}

{"title":"Droplet-Confined Electroplating for Nanoscale Additive Manufacturing: Current Control of the Initial Stages of Growth of Copper Nanowires.","authors":"Mirco Nydegger, Ralph Spolenak","doi":"10.1021/acselectrochem.4c00085","DOIUrl":"10.1021/acselectrochem.4c00085","url":null,"abstract":"<p><p>Droplet-confined electrodeposition enables a precise deposition of three-dimensional, nanoscopic, and high purity metal structures. It aspires to fabricate intricate microelectronic devices, metamaterials, plasmonic structures, and functionalized surfaces. Yet, a major handicap of droplet-confined electrodeposition is the current lack of control over the process, which is owed to its dynamic nature and the nanoscopic size of the involved droplets. The deposition current offers itself as an obvious and real-time window into the deposition and needs to be analyzed operando. Nucleation and growth dynamics are evaluated systematically. Our results indicate different deposition regimes and link the current to both morphology and volume of deposited copper. This allows for optimized electroplating strategies and calibration of the slicing algorithms necessary for a controlled deposition of 3D structures with different solvents. The potential of selecting appropriate solvents further readies this novel technique for the reliable deposition of functional structures with submicron resolution.</p>","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"1 2","pages":"205-215"},"PeriodicalIF":0.0,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11808642/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143401162","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}

{"title":"New Insights into the Hydrogen Evolution Mechanism near the Ni/YSZ Triple Phase Boundary during Steam Electrolysis: A Patterned Model Electrode Study.","authors":"Christoph W Thurner, Kevin Ploner, Daniel Werner, Simon Penner, Engelbert Portenkirchner, Bernhard Klötzer","doi":"10.1021/acselectrochem.4c00031","DOIUrl":"10.1021/acselectrochem.4c00031","url":null,"abstract":"<p><p>Solid oxide cell technologies play a crucial role in climate change mitigation by enabling the reversible storage of renewable energy. Understanding the electrochemical high-temperature reaction mechanisms and the catalytic role of the electrode and electrolyte materials is essential for advancing power-to-H₂ technologies. Despite its significance, limited <i>in situ</i> spectroscopic research focusing on nickel and yttria-stabilized zirconia (Ni/YSZ) is available. We employ near-ambient pressure X-ray photoelectron spectroscopy (NAP-XPS) to investigate 2D porous Ni/YSZ model electrodes with variable YSZ domain sizes and triple phase boundary (TPB) lengths. Focusing on the hydrogen evolution reaction (HER), we provide a mechanistic explanation for why surface hydroxylation and electrochemical activity are correlated with the YSZ surface area and YSZ domain size and unravel the specific mechanistic role of the YSZ surface. A direct comparison of normalization of the measured total electrolysis current to the purely geometrical length of the TPB vs an electrified \"catchment area\" next to the TPB, exhibiting strong enough electric fields, is the key to a correct quantitative description of the individual elementary steps of water electrolysis on Ni/YSZ. By combining electrochemical impedance spectroscopy, NAP-XPS, and electric field modeling, the local water reduction process near the TPB can be described, indicating optimized structural parameters for improved HER performance.</p>","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"1 3","pages":"315-327"},"PeriodicalIF":0.0,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11891889/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143607761","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}

{"title":"Optically Transparent Carbon Electrodes for Single Entity Electrochemistry.","authors":"Kelly L Vernon, Tipsiri Pungsrisai, Oluwasegun J Wahab, Sasha E Alden, Yaxu Zhong, Myung-Hoon Choi, Ekta Verma, Anne K Bentley, Kathleen O Bailey, Sara E Skrabalak, Xingchen Ye, Katherine A Willets, Lane A Baker","doi":"10.1021/acselectrochem.4c00048","DOIUrl":"10.1021/acselectrochem.4c00048","url":null,"abstract":"<p><p>We demonstrate the application and benefit of optically transparent carbon electrodes (OTCEs) for single entity nanoelectrochemistry. OTCEs are prepared by pyrolyzing thin photoresist films on fused quartz coverslips to create conductive, transparent, thin films. Optical, electrical, topographical, and electrochemical properties of OTCEs are characterized to evaluate their suitability for single entity electrochemistry. Nanoscale electrochemical imaging of the OTCEs using scanning electrochemical cell microscopy (SECCM) revealed uniform electrochemical activity for reduction of the hexaammineruthenium(III) redox complex, that was comparable to Au-coated glass, and in contrast to the heterogeneity observed with commonly used indium tin oxide (ITO) substrates. Additionally, we demonstrate the utility of the prepared OTCEs for correlative SECCM-scanning electron microscopy studies of the hydrogen evolution reaction at the surface of Au nanocubes. Lastly, we demonstrate the benefit of OTCEs for optoelectrochemical experiments by optically monitoring the electrodissolution of Au nanocrystals. These results establish OTCE as a viable transparent support electrode for multimode electrochemical and optical microscopy of nanocrystals and other entities.</p>","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"1 1","pages":"93-102"},"PeriodicalIF":0.0,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11728714/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143061845","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}

{"title":"<i>Operando</i> Electrochemical and Optical Characterization of the Meniscus of Scanning Electrochemical Cell Microscopy (SECCM) Probes.","authors":"Dimitrios Valavanis, Paolo Ciocci, Ian J McPherson, Gabriel N Meloni, Jean-François Lemineur, Frédéric Kanoufi, Patrick R Unwin","doi":"10.1021/acselectrochem.4c00029","DOIUrl":"10.1021/acselectrochem.4c00029","url":null,"abstract":"<p><p>We present a thorough description of the scanning electrochemical cell microscopy (SECCM) meniscus probe, in operation, by combining dual-channel SECCM measurements with <i>in situ</i> interference reflection microscopy (IRM). SECCM is a pipette-based nanoscale characterization tool with an unparalleled capacity for mapping the electrochemical activity of material surfaces, with high precision and at high throughput. In hopping mode, it operates by bringing the electrolyte meniscus, at the scanned pipette tip, in contact with the sample, restricting the probed area each time to a separate, newly wetted site, and forming a small-scale reactor. Each contact area can normally be imaged post-experiment, to inform on the wetted area stability and enable quantitative data interpretation (e.g., to calculate current density). However, the description of meniscus behavior during measurements would be beneficial. Herein, we utilize semi-transparent electrode substrates, to enable the direct optical observation, by IRM, of the meniscus status, with high spatial and temporal resolution, and synchronously to SECCM operation. The surface-sensitive optical method allows us to accurately capture the nature of the miniature electrochemical cell during all phases of the experiment-during approach, meniscus contact, wetting, and pipette withdrawal-and to follow subtle changes while in contact with the electrode substrate. Through the use of a dual-channel probe, we are able to monitor both the ionic current across the meniscus, between quasi-reference counter electrodes (QRCEs) under bias, and between the working electrode surface and the QRCEs. Correlating these electrochemical data and <i>operando</i> optical information via the hybrid SECCM-IRM approach aids the design of experimental protocols, streamlines the interpretation of results, and paints a comprehensive picture of meniscus wetting behavior.</p>","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"1 2","pages":"153-163"},"PeriodicalIF":0.0,"publicationDate":"2024-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11808645/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143401159","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}