The mechanism and kinetics of the electro-catalytic oxidation of hydrazine by graphene oxide platelets randomly decorated with palladium nanoparticles are deduced using single particle impact electrochemical measureme...The mechanism and kinetics of the electro-catalytic oxidation of hydrazine by graphene oxide platelets randomly decorated with palladium nanoparticles are deduced using single particle impact electrochemical measurements in buffered aqueous solutions across the pH range 2–11. Both hydrazine, N2H4, and protonated hydrazine N2H5+ are shown to be electroactive following Butler-Volmer kinetics, of which the relative contribution is strongly pH-dependent. The negligible interconversion between N2H4 and N2H5+ due to the sufficiently short timescale of the impact voltammetry, allows the analysis of the two electron transfer rates from impact signals thus reflecting the composition of the bulk solution at the pH in question. In this way the rate determining step in the oxidation of each specie is deduced to be a one electron step in which no protons are released and so likely corresponds to the initial formation of a very short-lived radical cation either in solution or adsorbed on the platelet. Overall the work establishes a generic method for the elucidation of the rate determining electron transfer in a multistep process free from any complexity imposed by preceding or following chemical reactions which occur on the timescale of conventional voltammetry.展开更多
Although considerable research efforts have been devoted to the design and development of non-noble electrocatalysts for oxygen evolution reaction(OER), substantial enhancement of OER performance with commercial-scale...Although considerable research efforts have been devoted to the design and development of non-noble electrocatalysts for oxygen evolution reaction(OER), substantial enhancement of OER performance with commercial-scale water electrolysis remains a big challenge. This could result from the difficulties in detecting the intrinsic properties and overlooking the assembly process for electrochemical OER process. Here, we employ a microjet collision method to investigate the intrinsic OER activities of individual NiZnFeO_x entities with and without a moderate magnetic field. Our results demonstrate that single NiZnFeO_x nanoparticles(NPs) show the excellent OER performance with a lowest onset potential(~1.35 V vs. RHE) and a greatest magnetic enhancement(~118%) among bulk materials, single agglomerations and NPs. Furthermore, we explore the utility of theoretical investigation by density functional theory(DFT)calculations for studying OER process on NiZnFeO_x surfaces without and with spin alignment, indicating monodispersed NiZnFeO_xNPs with totally spin alignment facilitates the OER process under the external magnetic field. It is found that the well-dispersion of NiZnFeO_x NPs would increase the electrical conductivity and the surface spin state, resulting in promoting their OER activities. This work provides a test for uncovering the essential roles of NPs assembly to a significant promotion of their magnet-assisted OER.展开更多
The manipulation of nanometric objects,encompassing both non-biological and biological objects,offers a transformative avenue for breakthroughs in diverse fields,such as chemistry,biology,chemical and biomedical engin...The manipulation of nanometric objects,encompassing both non-biological and biological objects,offers a transformative avenue for breakthroughs in diverse fields,such as chemistry,biology,chemical and biomedical engineering,materials and mechanical engineering,and various industrial applications.However,achieving accuracy,precision,and high throughput in the manipulation of nanometric objects,whether on the scale of a single nanometric entity or molecule,is a formidable challenge because of the extremely small dimensions involved.Nanofluidics has already demonstrated unique capabilities for transporting the mass of ions and small molecules at the nanoscale.We posit that chip-based nanofluidic devices provide potent strategies for the precise,accurate,and high-throughput manipulation of single nanometric entities and molecules,benefiting from their dimensions,which are comparable to those of nanometric objects.This article offers an overview of the current progress in nanofluidic manipulation of single nanometric objects.It also discusses the challenges in the development of nanofluidic manipulation technologies.Furthermore,the article explores future opportunities in the field,highlighting possible solutions to the challenges,and aims to contribute to the ongoing discourse on nanofluidic manipulation,thus propelling the field to overcome its current limitations.展开更多
Measurements at the single-entity level provide more precise diagnosis and understanding of basic biological and chemical processes.Recent advances in the chemical measurement provide a means for ultra-sensitive analy...Measurements at the single-entity level provide more precise diagnosis and understanding of basic biological and chemical processes.Recent advances in the chemical measurement provide a means for ultra-sensitive analysis.Confining the single analyte and electrons near the sensing interface can greatly enhance the sensitivity and selectivity.In this review,we summarize the recent progress in single-entity electrochemistry of single molecules,single particles,single cells and even brain analysis.The benefits of confining these entities to a compatible size sensing interface are exemplified.Finally,the opportunities and challenges of single entity electrochemistry are addressed.展开更多
The fabrication and electrochemical interrogation of very high density single-antibody nanoarrays is reported.Gold nanodots,15 nm in diameter,arranged in large(cm2)square arrays with a pitch of 200 nm,are used as carr...The fabrication and electrochemical interrogation of very high density single-antibody nanoarrays is reported.Gold nanodots,15 nm in diameter,arranged in large(cm2)square arrays with a pitch of 200 nm,are used as carriers for primary antibodies(immunoglobulin G(IgG)),further recognized by secondary redox-labeled detection antibodies.Ensemble scale interrogation of the antibody array by cyclic voltammetry,and nanoscale interrogation of individual nanodots by mediator tethered atomic forcescanning electrochemical microscopy(Mt/AFM-SECM),enable the occupancy of nanodots by single antibody molecules to be demonstrated.Experiments involving the competitive adsorption of antibodies of different species onto the nanodots evidence the possibility of using single-antibody nanoarrays for digital electrochemical immunoassays.展开更多
Ensemble averaging measurements obscure the link between the electrochemical performance and the specific properties of an individual because of the interplay of inhomogeneity and heterogeneity.Nanocollision electroch...Ensemble averaging measurements obscure the link between the electrochemical performance and the specific properties of an individual because of the interplay of inhomogeneity and heterogeneity.Nanocollision electrochemistry has attracted increasing interest because of its extremely high sensitivity,revealing the intrinsic properties of individual entities that are masked in the traditional ensemble measurements.In this perspective review,we summarized the recent developments in nanocollision-based single entity electrochemistry and photoelectrochemistry,the combined nanocollision electrochemistry with the other complementary techniques,as well as accurate data process.In closing,future challenges,opportunities,and destinations related to nanocollison electrochemistry were discussed.展开更多
Scanning electrochemical cell microscopy(SECCM)is increasingly applied to determine the intrinsic catalytic activity of single electrocatalyst particle.This is especially feasible if the catalyst nanoparticles are lar...Scanning electrochemical cell microscopy(SECCM)is increasingly applied to determine the intrinsic catalytic activity of single electrocatalyst particle.This is especially feasible if the catalyst nanoparticles are large enough that they can be found and counted in post-SECCM scanning electron microscopy images.Evidently,this becomes impossible for very small nanoparticles and hence,a catalytic current measured in one landing zone of the SECCM droplet cannot be correlated to the exact number of catalyst particles.We show,that by introducing a ruler method employing a carbon nanoelectrode decorated with a countable number of the same catalyst particles from which the catalytic activity can be determined,the activity determined using SECCM from many spots can be converted in the intrinsic catalytic activity of a certain number of catalyst nanoparticles.展开更多
Electrochemiluminescence(ECL)is a typical luminescence process triggered by electrochemical reactions.Due to the separated signal types,ECL measurements have some merits of high sensitivity,low background,and simple c...Electrochemiluminescence(ECL)is a typical luminescence process triggered by electrochemical reactions.Due to the separated signal types,ECL measurements have some merits of high sensitivity,low background,and simple configuration.Coupled with a microscopy setup,ECL microscopy(ECLM)has the unique characteristics of ECL and is also furnished with spatiotemporal resolution.Thus,many applications have been created,including nanoscale sensing,ECL mechanism deciphering,transient events of single objects,and ECLM crossover methods.In this review,we will overview the development and basic knowledge of ECL and then profile the setup design of ECLM.Through the understanding of these two parts,we will next probe the diverse applications of ECLM,combining the inter-relation with each other.Finally,the outlook discussing the expectations of further progress of ECLM technology.展开更多
基金Open access funding provided by University of Oxford.
文摘The mechanism and kinetics of the electro-catalytic oxidation of hydrazine by graphene oxide platelets randomly decorated with palladium nanoparticles are deduced using single particle impact electrochemical measurements in buffered aqueous solutions across the pH range 2–11. Both hydrazine, N2H4, and protonated hydrazine N2H5+ are shown to be electroactive following Butler-Volmer kinetics, of which the relative contribution is strongly pH-dependent. The negligible interconversion between N2H4 and N2H5+ due to the sufficiently short timescale of the impact voltammetry, allows the analysis of the two electron transfer rates from impact signals thus reflecting the composition of the bulk solution at the pH in question. In this way the rate determining step in the oxidation of each specie is deduced to be a one electron step in which no protons are released and so likely corresponds to the initial formation of a very short-lived radical cation either in solution or adsorbed on the platelet. Overall the work establishes a generic method for the elucidation of the rate determining electron transfer in a multistep process free from any complexity imposed by preceding or following chemical reactions which occur on the timescale of conventional voltammetry.
基金supported by the Major Research Project (No.92061108)the National Natural Science Foundation of China (No.22272052)+2 种基金Shanghai Municipal Science and Technology Major Project (No.2018SHZDZX03)Xiamen University Opening Project of PCOSS (No.201901)Yongjiang Talent Introduction Programme(No.2021A-115-G)。
文摘Although considerable research efforts have been devoted to the design and development of non-noble electrocatalysts for oxygen evolution reaction(OER), substantial enhancement of OER performance with commercial-scale water electrolysis remains a big challenge. This could result from the difficulties in detecting the intrinsic properties and overlooking the assembly process for electrochemical OER process. Here, we employ a microjet collision method to investigate the intrinsic OER activities of individual NiZnFeO_x entities with and without a moderate magnetic field. Our results demonstrate that single NiZnFeO_x nanoparticles(NPs) show the excellent OER performance with a lowest onset potential(~1.35 V vs. RHE) and a greatest magnetic enhancement(~118%) among bulk materials, single agglomerations and NPs. Furthermore, we explore the utility of theoretical investigation by density functional theory(DFT)calculations for studying OER process on NiZnFeO_x surfaces without and with spin alignment, indicating monodispersed NiZnFeO_xNPs with totally spin alignment facilitates the OER process under the external magnetic field. It is found that the well-dispersion of NiZnFeO_x NPs would increase the electrical conductivity and the surface spin state, resulting in promoting their OER activities. This work provides a test for uncovering the essential roles of NPs assembly to a significant promotion of their magnet-assisted OER.
基金partially supported by Japan Society for the Promotion of Science Grants-in-Aid for Scientific Research(JSPS KAKENHI)(JP21H04640,JP23KF0274,JP24KF0160,JP19KK0129,JP20H00497,JP18H01848,JP16K13653,JP26706010,and JP26630403)Ministry of Education,Culture,Sports,Science and Technology Grants-in-Aid for Scientific Research(MEXT KAKENHI)(JP21H05231,JP19H04678,JP17H05468,and JP26107714)+4 种基金Japan Science and Technology Agency Precursory Research for Embryonic Science and Technology(JST PRESTO)(JPMJPR18H5)Core Research for Evolutionary Science and Technology(CREST)(JPMJCR18H2)the Asahi Glass Foundation,Japanthe support received from the Japan Society for the Promotion of Science(JSPS)(P23374)the Development and Promotion of the Science and Technology Talents Project of Thailand(DPST532133)。
文摘The manipulation of nanometric objects,encompassing both non-biological and biological objects,offers a transformative avenue for breakthroughs in diverse fields,such as chemistry,biology,chemical and biomedical engineering,materials and mechanical engineering,and various industrial applications.However,achieving accuracy,precision,and high throughput in the manipulation of nanometric objects,whether on the scale of a single nanometric entity or molecule,is a formidable challenge because of the extremely small dimensions involved.Nanofluidics has already demonstrated unique capabilities for transporting the mass of ions and small molecules at the nanoscale.We posit that chip-based nanofluidic devices provide potent strategies for the precise,accurate,and high-throughput manipulation of single nanometric entities and molecules,benefiting from their dimensions,which are comparable to those of nanometric objects.This article offers an overview of the current progress in nanofluidic manipulation of single nanometric objects.It also discusses the challenges in the development of nanofluidic manipulation technologies.Furthermore,the article explores future opportunities in the field,highlighting possible solutions to the challenges,and aims to contribute to the ongoing discourse on nanofluidic manipulation,thus propelling the field to overcome its current limitations.
基金funding from National Natural Science Foundation of China(21834001,21925403,21874070,21790390,21790391,61901171)sponsored by National Ten Thousand Talent Program for young topnotch talent,funding from the European Union’s Horizon 2020research and innovation programme under the Marie Skodowska-Curie grant agreement No 812398,funding supported by the Strategic Priority Research Program of Chinese Academy of Sciences(XDB30000000)+5 种基金the National Basic Research Program of China(2018YFE0200800,2018YFA0703501 and 2016YFA0200104)the Chinese Academy of Sciences(QYZDJSSW-SLH030)funding from Office of Naval Research(N00014-19-1-2331)the US Air Force Office of Scientific Research MURI(FA9550-14-1-0003)the Nanostructures for Electrical Energy Storage(NEES)an Energy Frontier Research Center funded by the US Department of Energy,Office of Science and Basic Energy Sciences under Award number DESC0001160,support from the Office of Naval Research DURIP program(N00014-18-1-2235)。
文摘Measurements at the single-entity level provide more precise diagnosis and understanding of basic biological and chemical processes.Recent advances in the chemical measurement provide a means for ultra-sensitive analysis.Confining the single analyte and electrons near the sensing interface can greatly enhance the sensitivity and selectivity.In this review,we summarize the recent progress in single-entity electrochemistry of single molecules,single particles,single cells and even brain analysis.The benefits of confining these entities to a compatible size sensing interface are exemplified.Finally,the opportunities and challenges of single entity electrochemistry are addressed.
文摘The fabrication and electrochemical interrogation of very high density single-antibody nanoarrays is reported.Gold nanodots,15 nm in diameter,arranged in large(cm2)square arrays with a pitch of 200 nm,are used as carriers for primary antibodies(immunoglobulin G(IgG)),further recognized by secondary redox-labeled detection antibodies.Ensemble scale interrogation of the antibody array by cyclic voltammetry,and nanoscale interrogation of individual nanodots by mediator tethered atomic forcescanning electrochemical microscopy(Mt/AFM-SECM),enable the occupancy of nanodots by single antibody molecules to be demonstrated.Experiments involving the competitive adsorption of antibodies of different species onto the nanodots evidence the possibility of using single-antibody nanoarrays for digital electrochemical immunoassays.
基金supported by the National Natural Science Foundation of China (21775043, 21421004)the Program of Introducing Talents of Discipline to Universities (B16017)+1 种基金Innovation Program of Shanghai Municipal Education Commission (2017-01-07-00-02E00023)the Fundamental Research Funds for the Central Universities (222201718001, 222201717003)
文摘Ensemble averaging measurements obscure the link between the electrochemical performance and the specific properties of an individual because of the interplay of inhomogeneity and heterogeneity.Nanocollision electrochemistry has attracted increasing interest because of its extremely high sensitivity,revealing the intrinsic properties of individual entities that are masked in the traditional ensemble measurements.In this perspective review,we summarized the recent developments in nanocollision-based single entity electrochemistry and photoelectrochemistry,the combined nanocollision electrochemistry with the other complementary techniques,as well as accurate data process.In closing,future challenges,opportunities,and destinations related to nanocollison electrochemistry were discussed.
基金funding from the European Research Council(ERC)under the European Unions Horizon 2020 research and innovation programme(grant agreement CasCat[833408])well as from the European Unions Horizon 2020 research and innovation program under the Marie Sktodowska-Curie MSCA-ITN Single-Entity Nanoelectrochemistry,Sentinel[812398]+2 种基金S.S.and C.A.acknowledge the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)within the project[440951282]X.X.C.acknowledges financial support from the Liaoning BaiQianWan Talents Program,China(No.2019B042)the Excellent Young Scientific and Technological Talents Project of Educational Department of Liaoning Province,China(No.2020LNQN07).
文摘Scanning electrochemical cell microscopy(SECCM)is increasingly applied to determine the intrinsic catalytic activity of single electrocatalyst particle.This is especially feasible if the catalyst nanoparticles are large enough that they can be found and counted in post-SECCM scanning electron microscopy images.Evidently,this becomes impossible for very small nanoparticles and hence,a catalytic current measured in one landing zone of the SECCM droplet cannot be correlated to the exact number of catalyst particles.We show,that by introducing a ruler method employing a carbon nanoelectrode decorated with a countable number of the same catalyst particles from which the catalytic activity can be determined,the activity determined using SECCM from many spots can be converted in the intrinsic catalytic activity of a certain number of catalyst nanoparticles.
基金supported by the National Natural Science Foundation of China(Grant Nos.21834004,22174061,and 21904063)the Natural Science Foundation of Jiangsu Province(Grant No.BK20190279)+1 种基金Yangzhou University Interdisciplinary Research Foundation for Chemistry Discipline of Targeted Support(yzuxk202009)Foundation of State Key Laboratory of Analytical Chemistry for Life Science(Grant No.SKLACLS2201).
文摘Electrochemiluminescence(ECL)is a typical luminescence process triggered by electrochemical reactions.Due to the separated signal types,ECL measurements have some merits of high sensitivity,low background,and simple configuration.Coupled with a microscopy setup,ECL microscopy(ECLM)has the unique characteristics of ECL and is also furnished with spatiotemporal resolution.Thus,many applications have been created,including nanoscale sensing,ECL mechanism deciphering,transient events of single objects,and ECLM crossover methods.In this review,we will overview the development and basic knowledge of ECL and then profile the setup design of ECLM.Through the understanding of these two parts,we will next probe the diverse applications of ECLM,combining the inter-relation with each other.Finally,the outlook discussing the expectations of further progress of ECLM technology.
