Electrochemical science advances最新文献

{"title":"Electrochemical and spectral studies of rhodanine in view of heavy metals determination","authors":"Ovidiu Teodor Matica,&nbsp;Alina Giorgiana Brotea,&nbsp;Eleonora-Mihaela Ungureanu,&nbsp;Luisa Roxana Mandoc,&nbsp;Liviu Birzan","doi":"10.1002/elsa.202100218","DOIUrl":"10.1002/elsa.202100218","url":null,"abstract":"<p>The electrochemical study of 2-Sulfanylidene-1,3-thiazolidin-4-one (rhodanine, <b>R</b>) was performed on a glassy carbon working electrode by using three methods: differential pulse voltammetry (DPV), cyclic voltammetry (CV), and linear sweep voltammetry (LSV) at rotating disk electrode voltammetry (RDE). The CV, DPV, and LSV at RDE curves for <b>R</b> were recorded at different concentrations in 0.1 M TBAP/CH₃CN. Polymeric films were formed by successive cycling at different potentials and by controlled potential electrolysis. The film formation was proved by recording the CV curves of the chemically modified electrodes (CMEs) in transfer solutions containing ferrocene in 0.1 M TBAP/CH₃CN. The obtained CMEs were used for the detection of heavy metal ions. Synthetic samples of heavy metal ions (Cd (II), Pb (II), Cu (II), Hg (II)) of concentrations between 10⁻⁷ and 10⁻⁵ M were analyzed using CMEs prepared in different conditions. The most intense signal was obtained for Pb(II) ion (estimated detection limit = 10⁻⁷ M), which shows that these CMEs can be used for Pb(II) ion detection. The ability of <b>R</b> to form complexes with Pb(II) ion was also tested by UV-Vis spectrometry. The obtained results showed the formation of Pb(II)<b>R</b>₂ as the most stable complex.</p>","PeriodicalId":93746,"journal":{"name":"Electrochemical science advances","volume":"3 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://chemistry-europe.onlinelibrary.wiley.com/doi/epdf/10.1002/elsa.202100218","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43645539","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":"Surface microstructures and oxygen evolution properties of cobalt oxide deposited on Ir(111) and Pt(111) single crystal substrates","authors":"Naoto Todoroki,&nbsp;Hiroto Tsurumaki,&nbsp;Arata Shinomiya,&nbsp;Toshimasa Wadayama","doi":"10.1002/elsa.202200007","DOIUrl":"10.1002/elsa.202200007","url":null,"abstract":"<p>We investigated the oxygen evolution reaction (OER) activity changes of cobalt oxide (CoO<i>_x</i>) thin films on Ir(111) and Pt(111) substrates by repeated OER measurements in 0.1 M KOH. Atomic force microscopy and X-ray photoelectron spectroscopy analysis of the as-prepared CoO<i>_x</i>/Ir(111) and CoO<i>_x</i>/Pt(111) showed similar surface morphologies of the CoO<i>_x</i> thin films and almost the same OER overpotentials, which were estimated to be around 430 mV. However, after three OER measurements, the overpotential of CoO<i>_x</i>/Ir(111) decreased by 70 mV, whereas that of CoO<i>_x</i>/Pt(111) increased slightly. Structural analysis showed that CoO<i>_x</i>/Ir(111) revealed the island-like nanostructures of CoO<i>_x</i> dispersed on Ir(111) surface, accompanied by the generation of CoOOH. In contrast, for CoO<i>_x</i>/Pt(111), the Pt(111) substrate remains covered by the CoO<i>_x</i> thin film. The results suggest that the interaface at CoO<i>_x</i> (CoOOH) nano-islands and Ir(111) substrate are responsible for reducing the OER overpotential.</p>","PeriodicalId":93746,"journal":{"name":"Electrochemical science advances","volume":"3 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://chemistry-europe.onlinelibrary.wiley.com/doi/epdf/10.1002/elsa.202200007","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43907437","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":"Unprecedented formation of reactive BrO– ions and their role as mediators for organic compounds degradation: The fate of bromide ions released during the anodic oxidation of Bromophenol blue dye","authors":"Camila Carvalho de Almeida,&nbsp;Soliu O. Ganiyu,&nbsp;Carlos A. Martínez-Huitle,&nbsp;Elisama Vieira dos Santos,&nbsp;Katlin Ivon Barrios Eguiluz,&nbsp;Giancarlo Richard Salazar-Banda","doi":"10.1002/elsa.202100225","DOIUrl":"10.1002/elsa.202100225","url":null,"abstract":"<p>Based on the existing literature, active chlorine-mediated electrochemical oxidation has been extensively studied when Cl^‒ is added or Cl^‒ is already present in the water matrices, as well as when Cl^‒ is released from the target organic pollutants during their degradation. However, no attempts have been published concerning the fate and role of bromide (Br^‒) ions released during the anodic oxidation (AO) of organobromine compounds. Therefore, the AO of bromophenol blue dye (BPB) was investigated in a parallel plate flow reactor using a boron-doped diamond (BDD) anode. The effect of the applied current on the color removal efficiency and mineralization of BPB solution was examined and compared with AO of phenol red (PR) which has a similar molecular structure to BPB (but without Br) in order to understand the role of Br heteroatoms on the mineralization of BPB. Faster and higher mineralization and discoloration were achieved when treated with BPB solution compared to PR under similar experimental conditions. This behavior was associated with the electrogeneration of BrO^‒, from the heteroatom Br which is released as the bromide ion (Br^‒), during the degradation of BPB. The active bromine species are formed via direct and indirect oxidation approaches which were proposed based on ion chromatography and linear scanning voltammetry analysis.</p>","PeriodicalId":93746,"journal":{"name":"Electrochemical science advances","volume":"3 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://chemistry-europe.onlinelibrary.wiley.com/doi/epdf/10.1002/elsa.202100225","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47135054","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":"Designing multinary noble metal-free catalyst for hydrogen evolution reaction","authors":"Wissam A. Saidi,&nbsp;Tarak Nandi,&nbsp;Timothy Yang","doi":"10.1002/elsa.202100224","DOIUrl":"10.1002/elsa.202100224","url":null,"abstract":"<p>The hydrogen evolution reaction (HER), the key reaction for electrocatalytic production of hydrogen, is of fundamental importance due to its simplicity yet is very important for renewable energy. Notwithstanding, Pt is still the main catalyst for this reaction, which is not practical for the industrial deployment of this technology owing to the high cost and scarcity of Pt. The successful synthesis of high entropy alloy (HEA) nanoparticles opens a new frontier for the development of new catalysts. Herein we investigate the design of a multinary noble metal-free HER catalyst based on earth-abundant elements Co, Mo, Fe, Ni, and Cu. Using a machine learning (ML) approach in conjunction with first-principles methods, we build a model that can rapidly compute the hydrogen adsorption energy on the alloyed surfaces with high fidelity. Within the large composition space of the CoMoFeNiCu HEA, a large number of alloy combinations are shown to optimally bind hydrogen with a high probability. Further, most of these alloy compositions are found stable against dissociation into intermetallics, and hence synthesizable as a solid solution, by virtue of a large mixing entropy compared to mixing enthalpy and a small lattice mismatch between the elements. This finding is partly consistent with recent experimental results that synthesized five different CoMoFeNiCu HEA compositions. Our study underscores the significant impact that computational modeling and ML can have on developing new cost-effective electrocatalysts in the nearly-infinite materials design space of HEAs, and calls for experimental validation.</p>","PeriodicalId":93746,"journal":{"name":"Electrochemical science advances","volume":"3 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://chemistry-europe.onlinelibrary.wiley.com/doi/epdf/10.1002/elsa.202100224","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43228854","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":"From ion-sensitive field-effect transistor to 2D materials field-effect-transistor biosensors","authors":"Silvia Rizzato,&nbsp;Anna Grazia Monteduro,&nbsp;Angelo Leo,&nbsp;Maria Teresa Todaro,&nbsp;Giuseppe Maruccio","doi":"10.1002/elsa.202200006","DOIUrl":"10.1002/elsa.202200006","url":null,"abstract":"<p>Field-effect transistors have strong applications in biosensing field from pH and glucose monitoring to genomics, proteomics, cell signaling assays, and biomedical diagnostics in general. Notable advantages are the high sensitivity (thanks to intrinsic amplification), quick response (useful for real-time monitoring), suitability for miniaturization, and compact portable read-out systems. The initial concept of ion-sensitive field-effect transistors evolved with the emergence of novel classes of materials beyond traditional semiconductors. Recently, 2D nanomaterials are redesigning the field providing superior performances with large surface-to-volume ratio, high carrier mobility, more effective local gating, high transconductance, and operation at low voltages. Here, after a brief conceptual introduction, we review progresses and perspectives of 2D materials field-effect-transistor biosensors with special focus on opportunities, most recent applications, present challenges, and future perspectives.</p>","PeriodicalId":93746,"journal":{"name":"Electrochemical science advances","volume":"3 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://chemistry-europe.onlinelibrary.wiley.com/doi/epdf/10.1002/elsa.202200006","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46643957","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 contributions: Rudolf Brdička (1906–1970)","authors":"Evgeny Katz","doi":"10.1002/elsa.202260005","DOIUrl":"10.1002/elsa.202260005","url":null,"abstract":"<p>Rudolf Brdička (Figure 1) was a Czech physical chemist and electrochemist, particularly known for his research on biomedical applications of polarography.</p><p>Brdička was a pupil and later a collaborator of Prof. Jaroslav Heyrovský (the inventor of the polarographic method and recipient of the Nobel Prize in 1959). Following his studies on polarography performed with Heyrovský, Brdička devoted all his scientific career to the use of polarography for different electroanalytical applications. Since at that time polarography was used for electrochemical analysis of small organic redox molecules and particularly for the detection of various inorganic cations and their complexes, Brdička studied the electrochemistry of cobalt cations (Co³⁺). While the Co³⁺ polarographic wave was following the expected redox behavior similar to other polarographic metal ion reactions, surprisingly very unusual polarographic waves were observed in the presence of some proteins. The observed phenomenon was explained as a catalytic redox process that involves complex formation between Co³⁺ cations with thiol (-SH) groups in the protein backbone. The polarographic waves were named Brdička waves. The exact mechanism, which involves two catalytic processes proceeding at different potentials, was elucidated in detail later (B. Raspor, <i>J. Electroanal. Chem</i>. <b>2001</b>, <i>503</i>, 159–162). It was shown that the electrochemical process includes the redox process of the thiol-complex of Co³⁺ and then catalytic reduction of H⁺ cations and H₂ evolution at more negative potentials, thus resulting in double polarographic waves. The observed waves were used as a very sensitive indication of proteins (note that it was a catalytic process) and the waves were specific to different kinds of proteins (note that they were dependent on the presence of thiol groups in the proteins). The Brdička waves were used in the analysis of protein-biomarkers of cancer and other health problems over several decades (Figure 2).</p><p>Presently, the polarographic analysis is not used and the Brdička waves have only historic interest. Notably, the Brdička waves originate from the redox processes of thiol groups in the peripheral lysine residues, thus is not related to the redox transformations of enzyme active centers, which are important for various biosensor and bioelectronic applications.</p><p>The author declares no conflict of interest.</p>","PeriodicalId":93746,"journal":{"name":"Electrochemical science advances","volume":"2 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://chemistry-europe.onlinelibrary.wiley.com/doi/epdf/10.1002/elsa.202260005","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46008420","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 contributions: Adolph Wilhelm Hermann Kolbe (1818–1884)","authors":"Evgeny Katz","doi":"10.1002/elsa.202260006","DOIUrl":"10.1002/elsa.202260006","url":null,"abstract":"<p>Hermann Kolbe (Figure 1) was a German scientist who greatly contributed to the development of organic chemistry, transforming it to the state as we know it now. Kolbe pioneered organic synthesis from inorganic sources and introduced the term “synthesis” in the meaning how we use it in chemistry now. His name is associated with several synthetic reactions in organic chemistry, e.g., the Kolbe-Schmitt reaction in the preparation of aspirin, the Kolbe nitrile synthesis, etc. His work is particularly remembered in connection to electrolysis of carboxylic acids resulting in the synthesis of various organic compounds, known as the Kolbe reaction.</p><p>The Kolbe reaction (Figure 2), proceeding as the electrolysis, results in the oxidative decarboxylation of carboxylic acids yielding free radicals, which dimerize producing symmetrical products. For example, the Kolbe electrolysis process can proceed in an aqueous solution of sodium acetate (Figure 2). The acetate ions get decomposed and form methyl radicals. These combine with other free methyl radicals, which leads to the generation of ethane. In general, Kolbe's electrolysis method uses sodium salts of fatty acids to form the corresponding alkanes as products (D. Klüh, W. Waldmüller, M. Gaderer, <i>Clean. Technol</i>. <b>2021</b>, <i>3</i>, 1–18). A similar electrochemical synthesis can be used to produce more sophisticated products (Figure 2B). If the initial mixture includes two different acids, the reaction results in three different products from the cross-reaction of two different free radicals. The Kolbe electrolytic decarboxylation of 1,2-dicarboxylic acids results in the formation of double or triple chemical bonds (Figure 3). When carboxylic groups are located at a longer distance in a molecule, the electrolytic decarboxylation may result in the intramolecular radical cyclization of the reaction product.</p><p>It should be noted that the Kolbe electrolysis reaction may result in the formation of numerous byproducts (Figure 4). The formation of side products depends on the ease of the follow-up oxidation, which leads to carbenium ions, and their subsequent rearrangements. The exact mechanism and kinetics study of the electrochemical Kolbe process have been investigated confirming the complexity of the electrochemical reaction (A.K. Vijh, B.E. Conway, <i>Chem. Rev</i>. <b>1967</b>, <i>67</i>, 6, 623-664).</p><p>The author declares no conflict of interest.</p>","PeriodicalId":93746,"journal":{"name":"Electrochemical science advances","volume":"2 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://chemistry-europe.onlinelibrary.wiley.com/doi/epdf/10.1002/elsa.202260006","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48320250","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":"Editorial Overview: Nanoscale Electrochemistry","authors":"Kim McKelvey,&nbsp;Qianjin Chen","doi":"10.1002/elsa.202260004","DOIUrl":"10.1002/elsa.202260004","url":null,"abstract":"&lt;p&gt;A central challenge in electrochemical sciences is that the electrochemical response of an electrode is dominated by nanoscale features on the surface, yet our traditional electrochemical techniques operate on a millimeter or greater length scales. For instance, when we make a cyclic voltammetry measurement on a millimeter-scale electrode, the signal we obtain is based on the average response of all the active sites across the surface while details such as the activities of each site, their spatial distribution, and dynamics cannot be revealed. Nanoscale electrochemistry raises this challenge and has developed a range of techniques to effectively “zoom in” to the micro or nanoscale and, ultimately, to single molecules and atoms, enabling precise measurement of dynamic electrochemical process. This special edition highlights the cutting edge of nanoscale electrochemical research, spanning nanoparticle structure-activity relationships to DNA sequencing and 3D printing.&lt;/p&gt;&lt;p&gt;A mainstay of modern nanoscale electrochemistry is the scanning droplet approach known as scanning electrochemical microscopy (SECCM). SECCM simply and effectively restricts an electrochemical measurement to micro or nanoscale region of a large sample surface. In this special edition (Table 1), Schuhmann and co-workers use SECCM to investigate the structure-activity relationships in a high entropy alloy and reveal that active site-specific activities can be detected with probes of dimensions below a micrometer.&lt;sup&gt;[1]&lt;/sup&gt; Takahashi and coworkers use SECCM to investigate the capacitive response of carbon surfaces with 100-nanometer resolution and evaluate the difference in degradation of HOPG occurring at the edge and basal planes.&lt;sup&gt;[2]&lt;/sup&gt; Caleb and co-workers apply a targeted electrochemical cell microscopy (TECCM) approach to isolate the electrocatalytic response of individual shape-controlled nanoparticles toward borohydride oxidation and reveal the significant variations in reactivity and stability for individual nanoparticles.&lt;sup&gt;[3]&lt;/sup&gt; In the review by Bentley, the author summarizes how SECCM has been used to study (nano)particle electrochemistry, often isolated single nanoparticles dispersed on inert supports, and sometimes at sub-particles level.&lt;sup&gt;[4]&lt;/sup&gt; Finally, Momotenko and coworkers review how scanning probe approaches, including but not limited to SECCM, can be utilized for micro and nanoscale electrochemical 3D printing, an innovative strategy for precise fabrication of micro and nanoscale structures.&lt;sup&gt;[5]&lt;/sup&gt;&lt;/p&gt;&lt;p&gt;A different approach of electrochemical measurements at nanointerfaces is nano-collision or nano-impact electrochemistry. Shen and Wang demonstrate three different configurations to investigate the size, surface charge, dielectric properties, and electrochemical features of individual graphene oxide sheets.&lt;sup&gt;[6]&lt;/sup&gt;&lt;/p&gt;&lt;p&gt;Another approach towards nanoscale electrochemistry is the advanced optical microscopy, where electro","PeriodicalId":93746,"journal":{"name":"Electrochemical science advances","volume":"2 5","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://chemistry-europe.onlinelibrary.wiley.com/doi/epdf/10.1002/elsa.202260004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49151344","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":"Bioelectrochemistry – A growing community with broad diversity","authors":"Sabine Kuss","doi":"10.1002/elsa.202260003","DOIUrl":"https://doi.org/10.1002/elsa.202260003","url":null,"abstract":"&lt;p&gt;In our ever-changing and evolving world, disciplines in natural sciences are rarely able to solve complex research questions on their own anymore. Interdisciplinary research has become crucial to allow humanity to adapt to rapidly developing challenges, such as climate change, emerging diseases, an aging society, and growing socioeconomic inequalities. As one of the most rapidly growing interdisciplinary fields, bioelectrochemistry connects researchers all around the world, aiming to approach questions at the interface of biology, microbiology, chemistry, physics, and engineering from a new perspective. What started as a small community has developed over the last 2 decades into a diverse research society that provides remarkable insights into disease mechanisms, biomarker discovery, and bio-energy-related technology, such as microbial fuel cells.&lt;/p&gt;&lt;p&gt;This special collection presents research papers of exceptional bioelectrochemical studies, showcasing advances in point-of-care biosensor development, mechanistic bioelectrochemical research as well as biological energy harvesting and conversion. Articles are dedicated to understanding complex biological systems related to illnesses and answering questions in medical research, biosynthesis, and sustainable energy applications by bioelectrochemistry that require a multi-disciplinary knowledge base and interdisciplinary technologies.&lt;/p&gt;&lt;p&gt;The importance of the development of point-of-care sensors cannot be overstated, as biosensors are crucially needed to tackle emerging pathogens and to advance treatment strategies for other illnesses. The detection of disease biomarkers by electrochemistry has received tremendous attention over the last decade. Diagnostic studies for neurodegenerative diseases, including Alzheimer's disease and Parkinson's disease, infectious diseases, heart disease, and sepsis are only a few examples of ample contributions within this field of research. A wonderful example of successful immunosensing of a biomarker related to various illnesses, including angiogenesis, atherosclerosis, heart failure, and sepsis, is the contribution by Campuzano. In this publication, growth arrest-specific 6 (GAS6) protein is detected in human plasma and cell secretomes at screen-printed electrodes. Using the electrochemistry of the hydroquinone system, GAS6 is detected at antibody-modified magnetic micro-particles and further recognized by streptavidin-horseradish peroxidase. The use of screen-printed electrodes and an analysis time of about 75 min carries a great potential for the implementation of this sensing assay to be further developed into a clinical diagnostic device. Biodegradable electrodes are an emerging type of biosensors, highly applicable to clinical settings. Vadgama presents an interesting approach for chronic wound monitoring through albumin-collagen cross-linked membranes. This study demonstrates that diffusion barrier membranes can be made from protein mats, selective for ","PeriodicalId":93746,"journal":{"name":"Electrochemical science advances","volume":"2 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://chemistry-europe.onlinelibrary.wiley.com/doi/epdf/10.1002/elsa.202260003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"137459565","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 contributions: Julius Tafel (1862–1918)","authors":"Evgeny Katz","doi":"10.1002/elsa.202260002","DOIUrl":"10.1002/elsa.202260002","url":null,"abstract":"<p>Julius Tafel (Figure 1) was a Swiss chemist and electrochemist. Tafel started his scientific career working on the field of organic chemistry with Hermann Emil Fischer, but soon changed his interests to electrochemistry after his work with Wilhelm Ostwald.</p><p>Then, Tafel's work was concentrated on the electrochemistry of organic compounds and relation between rates of electrochemical reactions and applied overpotentials. Tafel's name is presently associated with many electrochemical terms: Tafel equation, Tafel slope, Tafel rearrangement, and Tafel mechanism of hydrogen evolution.</p><p>The Tafel equation and the corresponding Tafel plot (Figure 2) in electrochemical kinetics are relating the rate of an electrochemical reaction (in terms of the current density [<i>i</i>] to the overpotential [<i>η</i>] applied). The Tafel equation was first deduced experimentally and was later shown to have a theoretical justification. Indeed, it represents a simplified version of the theoretically derived Butler–Volmer equation (Figure 2) when the overpotentials are rather high (|<i>η</i>| &gt; 0.1 V; Tafel region). For a large overpotential (anodic or cathodic), one part of the Butler–Volmer equation becomes negligible while the second part can be transformed to the Tafel equation. The Tafel slope (<i>A</i>) shows how much the overpotential needs to be increased to increase the reaction rate (which is current in electrochemistry) by 10-fold. In a simple case of a one-electron transfer electrochemical reaction, the Tafel slope is determined by the symmetry factors (<i>α_a</i> and <i>α_c</i>), which are usually ca. 0.5, translating to a Tafel slope (<i>A</i>) of 120 mV. The Tafel equation, empirically derived from his experiments with electrochemical evolution of H₂, laid the background for a new scientific area of electrochemical kinetics. Tafel is also credited for the discovery of the catalytic mechanism of hydrogen evolution (the Tafel mechanism), construction of a new kind of hydrogen coulometer used in his study of H₂ evolution. Also, he demonstrated that hydrocarbons with isomerized structures can be generated upon electrochemical reduction of the respective acetoacetic esters (named Tafel rearrangement) (Figure 3). This was an important method for the synthesis of certain hydrocarbons from alkylated ethyl acetoacetate, a reaction accompanied by the rearrangement reaction of the alkyl group.</p><p>The author declares no conflict of interest.</p>","PeriodicalId":93746,"journal":{"name":"Electrochemical science advances","volume":"2 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://chemistry-europe.onlinelibrary.wiley.com/doi/epdf/10.1002/elsa.202260002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42465043","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}