ACS electrochemistryPub Date : 2025-05-12eCollection Date: 2025-08-07DOI: 10.1021/acselectrochem.5c00085
Anjali John, Anna Dettlaff, Joshua J Tully, Julie V Macpherson
{"title":"Free-Standing Boron Doped Diamond Slot Electrodes for UV-Visible Spectroelectrochemistry: Electrochemical Advanced Oxidation and Metal Ion Reduction.","authors":"Anjali John, Anna Dettlaff, Joshua J Tully, Julie V Macpherson","doi":"10.1021/acselectrochem.5c00085","DOIUrl":"10.1021/acselectrochem.5c00085","url":null,"abstract":"<p><p>Boron doped diamond (BDD) has numerous advantages as an electrode material such as having a wide aqueous solvent window, water oxidation, which is thought to produce weakly adsorbed hydroxyl radicals, low background currents, and high electrochemical stability. While BDD has received interest as an optically transparent electrode for combined UV-Vis electrochemical measurements, there are no studies which use it in applications which capitalize significantly on the properties of BDD. In this paper, we describe the use of a BDD spectroelectrochemical (SEC) electrode, BDD<sub>SEC</sub>, fabricated from free-standing BDD (400 μm thickness) and containing laser-micromachined slot-shaped holes (360 μm wide). The electrode shows an optical transmittance of 63% within the wavelength range of 200 to 800 nm, which is the highest reported transmittance for a BDD SEC. UV-Vis electrochemical characterization measurements are made using the redox couple Ru-(bipy)<sub>3</sub> <sup>2+/3+</sup> over a wavelength range that indium tin oxide electrodes struggle to access due to high background absorption in the UV region. Time scales for Ru-(bipy)<sub>3</sub> <sup>2+</sup> conversion to Ru-(bipy)<sub>3</sub> <sup>3+</sup> in this setup are ascertained. We demonstrate the first <i>operando</i> measurements for removal of a UV-Vis active molecule (brilliant blue) using BDD<sub>SEC</sub> electrodes under advanced oxidation conditions. From the change in the UV-Vis absorption signal with time, comparative measurements of the removal rate as a function of applied potential can be obtained; specifically rate constants of 0.10 min<sup>-1</sup> (1.04 V), 0.24 min<sup>-1</sup> (at 1.39 V), and 0.68 min<sup>-1</sup> (at 2.22 V) <i>vs</i> Ag|AgCl (3 M Cl<sup>-</sup>) are determined for this experimental arrangement. At the highest potential, we propose both direct and indirect oxidation (via production of hydroxyl radicals from water) are possible. As a second application, we demonstrate the viability of the BDD<sub>SEC</sub> electrode for quantifying metal ion removal rates (via electroreduction) from different solvent systems. Specifically, we consider electrochemical removal of Pd from Pd-acetate in aqueous acid and in a mixed water:acetonitrile solution.</p>","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"1 8","pages":"1462-1471"},"PeriodicalIF":0.0,"publicationDate":"2025-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12337086/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144839792","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}
ACS electrochemistryPub Date : 2025-04-29eCollection Date: 2025-08-07DOI: 10.1021/acselectrochem.5c00040
Mai-Anh Ha, Emily K Volk, Oliver Leitner, Avital Isakov, Héctor J González Vélez, Shaun Alia, Ross Larsen
{"title":"Complex Degradation Mechanisms Accessible to Anion Exchange Membrane Ionomers on Model Catalysts, NiO and IrO<sub>2</sub>.","authors":"Mai-Anh Ha, Emily K Volk, Oliver Leitner, Avital Isakov, Héctor J González Vélez, Shaun Alia, Ross Larsen","doi":"10.1021/acselectrochem.5c00040","DOIUrl":"10.1021/acselectrochem.5c00040","url":null,"abstract":"<p><p>For anion exchange membrane (AEM) electrolysis to be cost- and performance-competitive to proton exchange membrane (PEM) electrolysis, evaluating and improving the stability of the ionomer at the ionomer-catalyst interface will be key to this emerging technology. Theoretical calculations of molecular fragments of the ionomers detailed the complex degradation mechanisms accessible to four different classes of ionomers (Nafion, Sustainion, Versogen, and quaternary ammonium typesETFE, Gen 2, and Georgia Tech) on model catalysts of platinum group metal IrO<sub>2</sub> and earth-abundant NiO. These mechanisms may occur during the making of the ionomer-catalyst ink or in the alkaline environment of AEM electrolysis or are energetically accessible at the electrochemical potentials of electrolysis. We identified diverse degradations such as (H)-SO<sub>4</sub> production, water formation, oxidation to an alcohol, and deprotonation, leading to ionomer instability and competing with the oxygen evolution reaction (OER). Theory predicted that the weakly bound, intact cations of Sustainion's methyl imidazolium on NiO and Versogen's piperidinium on NiO combinations to be particularly stable and active for OER; these findings were validated by half-cell rotating disk electrode tests, where following break-in, their performance increased by 7-8 times. IrO<sub>2</sub> may be stable and maintain OER activity, but site access remains limited due to the strong binding and reactivity of the ionomer at the high potentials of electrolysis (at 1.4 V, Nafion's SO<sub>3</sub> splits into SO<sub>2</sub> + O; at 0.6 V, double deprotonation of Versogen can occur; at 1.5 V, ring oxidation of Sustainion to an alcohol initiates).</p>","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"1 8","pages":"1339-1351"},"PeriodicalIF":0.0,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12337097/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144839788","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}
ACS electrochemistryPub Date : 2025-04-22eCollection Date: 2025-06-05DOI: 10.1021/acselectrochem.4c00155
Anna C Kundmann, John S Mangum, Mellie Lemon, Maria Kelly, Dennice M Roberts, Melissa K Gish, Elisa M Miller, Emily L Warren, Frank E Osterloh, Ann L Greenaway
{"title":"ZnTiN<sub>2</sub> as an Electron-Selective, Protective Layer on Si Photocathodes.","authors":"Anna C Kundmann, John S Mangum, Mellie Lemon, Maria Kelly, Dennice M Roberts, Melissa K Gish, Elisa M Miller, Emily L Warren, Frank E Osterloh, Ann L Greenaway","doi":"10.1021/acselectrochem.4c00155","DOIUrl":"10.1021/acselectrochem.4c00155","url":null,"abstract":"<p><p>Photoelectrochemical production of fuels requires photoelectrodes that efficiently convert sunlight to electrochemical energy by producing photovoltage and photocurrent and maintain this ability over time under a variety of pH, illumination, and applied bias conditions. Work in the photovoltaic community has demonstrated that interfaces with high charge carrier selectivity provide high photovoltages. This offers a co-design opportunity to create semiconductor photoelectrodes with contact layers that are both carrier-selective and offer protection from degradation in aqueous solutions. In this work, we explored the ternary nitride ZnTiN<sub>2</sub> as an electron-selective, protective layer for Si-based photocathodes. We demonstrated that ZnTiN<sub>2</sub> formed a heterojunction with p-type Si that facilitated electron movement toward the ZnTiN<sub>2</sub> surface for light-driven reduction reactions. Across a variety of electrolyte conditions, ZnTiN<sub>2</sub>/Si produced an open circuit voltage of ca. 400 mV vs the solution potential, while bare Si produced 220-480 mV vs the solution potential depending on conditions. ZnTiN<sub>2</sub> was also shown to protect Si over 72 h at open circuit in the dark in 0.1 M KHCO<sub>3</sub> aqueous solution at pH 10.5, with a 2.4% loss in open circuit voltage compared to a 17% loss for unprotected Si. A protective effect was also observed under illumination during methyl viologen reduction at pH 3.5 for 21 h, with a 2.5% loss in open circuit voltage observed for ZnTiN<sub>2</sub>/Si compared to a 25% loss in open circuit voltage for unprotected Si under the same conditions. Elemental characterization revealed the presence of oxides on the surface of ZnTiN<sub>2</sub> that are consistent with the Pourbaix diagram after photoelectrochemical operation; these oxides appeared to support durability without hindering charge carrier extraction to drive electrochemical work. This work highlights the promise of ZnTiN<sub>2</sub> for durable photoelectrochemical applications.</p>","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"1 6","pages":"842-852"},"PeriodicalIF":0.0,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12147160/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144268393","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}
ACS electrochemistryPub Date : 2025-04-22eCollection Date: 2025-05-01DOI: 10.1021/acselectrochem.4c00079
Brian Chen, Niya Hope-Glenn, Amanda Wright, Robert J Messinger, Alexander Couzis
{"title":"Mechanistic Understanding of Lithium-Ion Adsorption, Intercalation, and Plating during Charging of Graphite Electrodes.","authors":"Brian Chen, Niya Hope-Glenn, Amanda Wright, Robert J Messinger, Alexander Couzis","doi":"10.1021/acselectrochem.4c00079","DOIUrl":"https://doi.org/10.1021/acselectrochem.4c00079","url":null,"abstract":"<p><p>Low-temperature and fast-charging lithium (Li)-ion batteries remain challenging due to the undesirable Li plating on graphite anodes under these conditions. Here, we present a kinetic mechanism that underpins electrochemical Li<sup>+</sup> cation intercalation and Li metal plating reactions on graphite electrodes at low temperatures and fast rates. Variable-temperature (30 °C to -40 °C) and variable-rate (0.1 to 10 mA/cm<sup>2</sup>) constant-current measurements were conducted on three-electrode cells comprised of Li metal counter, graphite working, and Li metal reference electrodes, as well as two-electrode cells. The local minima in the potential profiles, often associated with the nucleation overpotential for Li metal plating on graphite, must be disentangled from contributions from Li metal stripping at the counter electrode. Differential capacity analyses of three-electrode measurements of graphite potential show that the extent of electrochemical Li<sup>+</sup> cation intercalation drops precipitously as temperature decreases below -20 °C. The temperature dependence of empirically defined rate constants for Li<sup>+</sup> cation intercalation and Li plating determined from constant-current measurements revealed non-Arrhenius behavior for Li<sup>+</sup> cation intercalation that suggests a two-step pre-equilibration mechanism, while typical Arrhenius behavior for Li plating suggests a unimolecular single-step process. A kinetic model based on Langmuir adsorption shows that the interfacial concentration of Li<sup>+</sup> cations adsorbed on graphite active sites is critical in dictating the kinetics of the charging process. We show that rate limitations, either adsorption-limited or surface reaction-limited, manifest at different temperatures and rates during the charging process. The results yield new mechanistic understanding of how Li<sup>+</sup> cations electrochemically compete for intercalation into and plating on graphite electrodes, as a function of temperature and charge rate.</p>","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"1 5","pages":"574-587"},"PeriodicalIF":0.0,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12051203/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144035191","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}
ACS electrochemistryPub Date : 2025-04-21eCollection Date: 2025-07-03DOI: 10.1021/acselectrochem.5c00095
Lingjie Zhang, Madison E Edwards, Oluwasegun J Wahab, Hugo Y Samayoa-Oviedo, Dallas P Freitas, Xin Yan, Lane A Baker
{"title":"Scanning Electrochemical Cell Microscopy for Sub-Micrometer Mass Spectrometric Studies of Electrochemical Reactions.","authors":"Lingjie Zhang, Madison E Edwards, Oluwasegun J Wahab, Hugo Y Samayoa-Oviedo, Dallas P Freitas, Xin Yan, Lane A Baker","doi":"10.1021/acselectrochem.5c00095","DOIUrl":"10.1021/acselectrochem.5c00095","url":null,"abstract":"<p><p>Nanoscale electrochemistry has been significantly advanced through the utilization of nanopipettes, enabling precise electrode area confinement and localized measurements. In particular, scanning electrochemical cell microscopy (SECCM) has leveraged the use of nanopipettes to facilitate measurement of electrochemical processes with high spatiotemporal resolution. While nano electrochemistry is well-suited to study processes at the sub-micrometer level, there is a need for complementary analytical techniques that can enable the detection of intermediates and help to elucidate reaction pathways that occur in the small volumes. In this work, we demonstrate the coupling of SECCM with MS for the detection of reaction products formed by the oxidation of uric acid. Specifically, species generated at the tip of an SECCM probe could be delivered to a mass spectrometer via nanoelectrospray ionization and exhibit both stable ion signal and high sensitivity. We demonstrate that this workflow enables the detection of analytes generated from SECCM probes of 3 μm and 900 nm tip diameter, despite the low conversion ratio associated with the smaller nanopipette diameters. Results presented herein demonstrate the SECCM-MS workflow as a powerful approach to detect low-abundance species formed from micro- and nanoscale electrochemical reactions.</p>","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"1 7","pages":"1066-1075"},"PeriodicalIF":0.0,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12235642/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144602714","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}
ACS electrochemistryPub Date : 2025-04-15eCollection Date: 2025-08-07DOI: 10.1021/acselectrochem.4c00218
Ožbej Vodeb, Pedro Farinazzo Bergamo Dias Martins, Dušan Strmčnik, Nejc Hodnik, Miran Gaberšček
{"title":"ElectroKitty: A Python Tool for Modeling Electrochemical Data Including Non-Langmuir Adsorption.","authors":"Ožbej Vodeb, Pedro Farinazzo Bergamo Dias Martins, Dušan Strmčnik, Nejc Hodnik, Miran Gaberšček","doi":"10.1021/acselectrochem.4c00218","DOIUrl":"10.1021/acselectrochem.4c00218","url":null,"abstract":"<p><p>The use of simulation and various forms of data analysis is becoming more frequent in all areas of electrochemistry. To support this, we have created ElectroKitty, a Python package that can simulate complex reaction pathways. Since experimental data often exhibits non-idealities with adsorbed species, we have programmed ElectroKitty to incorporate such corrections. To demonstrate the versatility of our package we selected four common reaction pathways and validated it against an established simulator. We also demonstrate the Frumkin isotherm and how ElectroKitty can reproduce it. In addition, to demonstrate the more advanced features of our package, we used ElectroKitty to simulate OH adsorption on a Pt(111) surface using a straightforward model.</p>","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"1 8","pages":"1540-1544"},"PeriodicalIF":0.0,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12337095/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144839791","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}
ACS electrochemistryPub Date : 2025-04-11eCollection Date: 2025-07-03DOI: 10.1021/acselectrochem.4c00241
Antonio J Martínez-García, José V Hernández-Tovar, Manuela López-Tenés, Joaquín González
{"title":"Molecular Electrocatalysis in Confined Spaces: Analysis of the Cyclic Staircase and Cyclic Voltammetry Responses.","authors":"Antonio J Martínez-García, José V Hernández-Tovar, Manuela López-Tenés, Joaquín González","doi":"10.1021/acselectrochem.4c00241","DOIUrl":"10.1021/acselectrochem.4c00241","url":null,"abstract":"<p><p>Molecular electrocatalytic processes in confined environments are becoming relevant processes with many applications in electrosynthesis, electroanalysis, and electrical energy generation and conversion. Nevertheless, the analysis of catalytic responses is mostly carried out with theoretical frameworks developed for semi-infinite linear diffusion conditions, which are not applicable for the adequate understanding of electrochemical processes in confined spaces. To fill the existing gap in the comprehension of these complex reactions, the analysis of a molecular catalytic process under finite diffusive conditions for cyclic staircase voltammetry (CSCV) and cyclic voltammetry (CV) techniques is presented in this work. The proposed model considers a finite diffusive field of thickness <i>L</i> under two configurations: bounded diffusion, where no mass renovation is allowed, and unbounded diffusion, where there is effective mass replenishment at <i>L</i>. Expressions for the current-potential responses under different particular cases have been obtained, leading to a kinetic zone diagram for limiting cases in terms of two key variables related to the thickness of the solution region and the catalytic rate constant. From the general expression of the current, it is observed that the electrochemical response of molecular electrocatalytic processes taking place in confined spaces is strongly dependent on the mass transport conditions. Thus, under bounded diffusion, a decrease of the catalytic current with <i>L</i> is observed, which is more pronounced when the diffusive field is narrower. On the other hand, unbounded conditions give rise to an enhancement of the catalytic current and, eventually, to the loss of the kinetic sensitivity of the response for small enough values of <i>L</i>. An experimental application of the theoretical results is performed for the conversion of isopropyl alcohol (IPA) to acetone mediated by the oxidation of 4-methoxy-2,2,6,6-tetra-methyl-1-piperi-dinyl-oxy (4-methoxy-TEMPO radical) at a glassy carbon electrode for both bound and unbounded configurations. The catalytic rate constant for this process has been obtained from the equations for the current, indicating that the accuracy of the result is strongly dependent on the correct understanding of the mass transport influences at play.</p>","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"1 7","pages":"1110-1124"},"PeriodicalIF":0.0,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12239016/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144610899","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}
ACS electrochemistryPub Date : 2025-04-03Epub Date: 2025-02-22DOI: 10.1021/acselectrochem.4c00117
Kaden Wheeler, Joseph Gott, Brian Roehrich, Julia Chung, Kajal Kajal, Jaroslaw Syzdek, Joao Hespanha, Lior Sepunaru
{"title":"Investigation of Noise at a Microelectrode during a Faradaic Reaction.","authors":"Kaden Wheeler, Joseph Gott, Brian Roehrich, Julia Chung, Kajal Kajal, Jaroslaw Syzdek, Joao Hespanha, Lior Sepunaru","doi":"10.1021/acselectrochem.4c00117","DOIUrl":"10.1021/acselectrochem.4c00117","url":null,"abstract":"<p><p>Measurement of small currents is often impeded by a suboptimal signal-to-noise ratio, largely due to background noise. This background noise significantly constrains the range of catalysts accessible for interrogation via micro- and nanoscale electrochemistry. In response, this work reveals how background noise scales in the presence of induced Faradaic reactions. We measured noise under a series of electrochemical conditions and discovered that the induced noise from a Faradaic reaction scales directly with current. Complementary electrochemical impedance spectroscopy measurements demonstrated that diffusional resistance dictates the noise of Faradaic reactions, independent of the electrochemical mechanism. The noise source is thermal in origin and propagates in a predictable trend, which is inversely proportional to the equivalent diffusional resistance of the analyte. The universality of the observed phenomenon allows for better deconvolution of measured charge from background noise, thus assisting in achieving higher resolution and measurement precision, which is a key in micro- and nanoscale electrochemical measurements.</p>","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"1 4","pages":"552-559"},"PeriodicalIF":0.0,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12284577/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144700899","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}
ACS electrochemistryPub Date : 2025-03-27eCollection Date: 2025-05-01DOI: 10.1021/acselectrochem.4c00180
He Zhao, Owen Markow, Greatness Olaitan, Eric D Donarski, Kevin C Lester, Nickolay V Lavrik, B Jill Venton
{"title":"Pyrolyzed Parylene-N for <i>in Vivo</i> Electrochemical Detection of Neurotransmitters.","authors":"He Zhao, Owen Markow, Greatness Olaitan, Eric D Donarski, Kevin C Lester, Nickolay V Lavrik, B Jill Venton","doi":"10.1021/acselectrochem.4c00180","DOIUrl":"10.1021/acselectrochem.4c00180","url":null,"abstract":"<p><p>Carbon electrodes are typically used for <i>in vivo</i> dopamine detection, and new types of electrodes and customized fabrication methods will facilitate new applications. Parylene is an insulator that can be deposited in a thin layer on a substrate and then pyrolyzed to carbon to enable its use as an electrode. However, pyrolyzed parylene has not been used for the real-time detection of neurochemicals by fast-scan cyclic voltammetry. In this work, we deposited thin layers of parylene-N (PN) on metal wires and then pyrolyzed them to carbon with high temperatures in a rapid thermal processor (RTP). Different masses of PN, 1, 6, and 12 g, were deposited to vary the thickness. RTP-PN (6 g) produced a 194 nm layer carbon thickness and had optimal electrochemical stability. Pyrolyzed parylene-N modified electrodes (PPNMEs) were characterized for electrochemical detection of dopamine, serotonin, and adenosine. Background-normalized currents at PPNMEs were about 2 times larger than those of carbon-fiber microelectrodes (CFMEs). Rich defect sites and oxygen functional groups promoted the neurochemical adsorption of cationic neurotransmitters. PPNMEs resisted fouling from serotonin polymer formation. PPNMEs were used <i>in vivo</i> to detect stimulated dopamine release and monitor spontaneous adenosine release. Pyrolyzed parylene is a sensitive and fouling-resistant thin-film carbon electrode that could be used in the future for making customized electrodes and devices.</p>","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"1 5","pages":"730-740"},"PeriodicalIF":0.0,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12051191/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144057572","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}
ACS electrochemistryPub Date : 2025-03-22eCollection Date: 2025-06-05DOI: 10.1021/acselectrochem.5c00038
Fabiola Olmo, Martin Perez-Estebanez, Aranzazu Heras, Francisco Javier Del Campo, Alvaro Colina
{"title":"Simultaneous UV/vis Absorption in Parallel Configuration, Photoluminescence and Raman Spectroelectrochemistry.","authors":"Fabiola Olmo, Martin Perez-Estebanez, Aranzazu Heras, Francisco Javier Del Campo, Alvaro Colina","doi":"10.1021/acselectrochem.5c00038","DOIUrl":"10.1021/acselectrochem.5c00038","url":null,"abstract":"<p><p>Analytical Chemistry is the science of chemical measurements that seeks to acquire the most comprehensive information about a chemical system. Recent advances in technology have facilitated the development of new combined analytical techniques capable of supplying analytical signals of different natures. These signals subsequently provide diverse information related to specific chemical reactions. This technical note proposes a new combination of three different spectroscopic techniques (UV/vis absorption spectroscopy in a parallel configuration, photoluminescence and Raman spectroscopy) with electrochemistry. To illustrate the capabilities of this new technique, two chemical systems (tris-(2,2' bipyridine)-ruthenium-(II) and ofloxacin) were selected. A comparison of the behavior of the two molecules during the electrode process demonstrates the advantages of obtaining several signals simultaneously in a single experiment.</p>","PeriodicalId":520400,"journal":{"name":"ACS electrochemistry","volume":"1 6","pages":"997-1002"},"PeriodicalIF":0.0,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12147439/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144268352","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}