To address climate change and promote environmental sustainability,electrochemical energy conversion and storage systems emerge as promising alternative to fossil fuels,catering to the escalating demand for energy.Ach...To address climate change and promote environmental sustainability,electrochemical energy conversion and storage systems emerge as promising alternative to fossil fuels,catering to the escalating demand for energy.Achieving optimal energy efficiency and cost competitiveness in these systems requires the strategic design of electrocatalysts,coupled with a thorough comprehension of the underlying mechanisms and degradation behavior occurring during the electrocatalysis processes.Scanning electrochemical microscopy(SECM),an analytical technique for studying surface electrochemically,stands out as a powerful tool offering electrochemical insights.It possesses remarkable spatiotemporal resolution,enabling the visualization of the localized electrochemical activity and surface topography.This review compiles crucial research findings and recent breakthroughs in electrocatalytic processes utilizing the SECM methodology,specifically focusing on applications in electrolysis,fuel cells,and metal–oxygen batteries within the realm of energy conversion and storage systems.Commencing with an overview of each energy system,the review introduces the fundamental principles of SECM,and aiming to provide new perspectives and broadening the scope of applied research by describing the major research categories within SECM.展开更多
We report here the in situ electrochemical scanning tunneling microscopy(ECSTM) study of cobalt phthalocyanine(CoPc)-catalyzed O_(2) evolution reaction(OER) and the dynamics of CoPc-O_(2) dissociation.The self-assembl...We report here the in situ electrochemical scanning tunneling microscopy(ECSTM) study of cobalt phthalocyanine(CoPc)-catalyzed O_(2) evolution reaction(OER) and the dynamics of CoPc-O_(2) dissociation.The self-assembled CoPc monolayer is fabricated on Au(111) substrate and resolved by ECSTM in 0.1 M KOH electrolyte.The OH^(-)adsorption on CoPc prior to OER is observed in ECSTM images.During OER,the generated O_(2) adsorbed on Co Pc is observed in the CoPc monolayer.Potential step experiment is employed to monitor the desorption of OER-generated O_(2) from CoPc,which results in the decreasing surface coverage of CoPc-O_(2) with time.The rate constant of O_(2) desorption is evaluated through data fitting.The insights into the dynamics of Co-O_(2) dissociation at the molecular level via in situ imaging help understand the role of Co-O_(2) in oxygen reduction reaction(ORR) and OER.展开更多
The thiol-porphyrins were prepared to investigate the effect of spacer length on the gold electrode. These measurements showed that as the length of the spacers increases, the SAMs tend to form highly ordered structur...The thiol-porphyrins were prepared to investigate the effect of spacer length on the gold electrode. These measurements showed that as the length of the spacers increases, the SAMs tend to form highly ordered structures on the gold electrodes. In addition, the structures of the monoalyers vary depending on the even and odd number of the methylene spacers （n）.展开更多
The corrosion behavior of aluminum alloys 1060 and 2A12 in a 10 mM Na2SO4＋5 mM KI solution was investigated by scanning electrochemical microscopy （SECM） and scanning electron microscopy （SEM）. The potential topo...The corrosion behavior of aluminum alloys 1060 and 2A12 in a 10 mM Na2SO4＋5 mM KI solution was investigated by scanning electrochemical microscopy （SECM） and scanning electron microscopy （SEM）. The potential topography and corrosion morphology results show that the potential of the sample surface over the same area changes with the increase of immersion time. The corrosion area becomes large, and the potential becomes more negative. The corrosion potential of the 2A12 alloy surface is lower than that of 1060 aluminum, and 2A12 alloy becomes easily corrosive. This is the reason that preferential dissolution in the boundary region of some intermetallic particles （IMPs） occurs and different dissolution behaviors are associated with different types of IMPs because of different potentials.展开更多
The activity of horseradish peroxidase at b-cyclodextrin polymer was imaged by scanning electrochemical microscopy using 3, 3', 5, 5'-tetramethylbenzide and H2O2 as the substrates.
Development of reaction-tailored electrocatalysts is becoming increasingly important as energy and environment are among key issues governing our sustainable future.Electrocatalysts are inherently optimized for applic...Development of reaction-tailored electrocatalysts is becoming increasingly important as energy and environment are among key issues governing our sustainable future.Electrocatalysts are inherently optimized for application towards reactions of interest in renewable energy,such as those involved in water splitting and artificial photosynthesis,owing to its energy efficiency,simple fabrication,and ease of operation.In this view,it is important to secure logical design principles for the synthesis of electrocatalysts for various reactions of interest,and also understand their catalytic mechanisms in the respective reactions for improvements in further iterations.In this review,we introduce several key methods of scanning electrochemical microscopy(SECM)in its applications towards electrocatalysis.A brief history and a handful of seminal works in the SECM field is introduced in advancing the synthetic designs of electrocatalysts and elucidation of the operating mechanism.New developments in nano-sizing of the electrodes in attempts for improved spatial resolution of SECM is also introduced,and the application of nanoelectrodes towards the investigation of formerly inaccessible single catalytic entities is shared.展开更多
Elucidating the structure-activity relationship in electrocatalysis is of fundamental interest for electrochemical energy conversion and storage.However,the heterogeneity in the surface structure of electrocatalysts,i...Elucidating the structure-activity relationship in electrocatalysis is of fundamental interest for electrochemical energy conversion and storage.However,the heterogeneity in the surface structure of electrocatalysts,including the presence of various facets,poses an analytical challenge in revealing the true structure-activity relationship because the activity is conventionally measured on ensemble,resulting in an averaged activity that cannot be unequivocally associated with a single structural motif.Scanning electrochemical cell microscopy(SECCM)[1]combined with colocalized electron backscatter diffraction(EBSD)offers a direct way to reveal the correlative local electrochemical and structural information.Herein,we measured the hydrogen evolution reaction(HER)activity on Ag and its dependence on the crystal orientation.From the combined EBSD and SECCM mapping,it is found that Ag grains closer to{111}show a higher exchange current density,while those closer to{110}show a lower Tafel slope.The Tafel slope is also found to decrease with the step density increase.The ability to measure the electrocatalytic activity under a high mass-transfer rate allows us to reveal the activity difference at a high current density(up to 200 mA/cm^(2)).The approach reported here can be expanded to other systems to reveal the nature of active sites of electrocatalysis.展开更多
his paper covers the electropolymerized polypyrrole doped with p-toluenesul-fonate studied using scanning tunneling microscope. The growth processes of polypyrrole films on the electrode surface were observed. Polypy...his paper covers the electropolymerized polypyrrole doped with p-toluenesul-fonate studied using scanning tunneling microscope. The growth processes of polypyrrole films on the electrode surface were observed. Polypyrrole chain struc-ture with many separated micro-holes of 0. 15 nm diameter at the initial state ofelectropolymerization can be seen from obtained STM images. This structure is ex-tremely similar to the pioneer-proposed ideal structure of polypyrrole chains. Thereexisted some helical structure and simple strands on the electrode surface, which isdue to different existing states of polypyrrole chains on electrode surface. STM ex-periments showed that polypyrrole chains were firstly formed on the electrode sur-face, then, they growed gradually by 3-dimensional mode during slow oxidation toform many separated micro-islands. Finally, a large corrugation area of polymerfilms occurred on the electrodes.展开更多
A nover technique for the fabrication of the tip for e tectrochemical scanning tunneting microscopy(ECSTM)is presented. The curvature radius of the fabricated tip is smatter than 1 μM. Faradaic leakage current is tes...A nover technique for the fabrication of the tip for e tectrochemical scanning tunneting microscopy(ECSTM)is presented. The curvature radius of the fabricated tip is smatter than 1 μM. Faradaic leakage current is tess than 0.1nA in the sotution of 1 mol/L NaCl. The atomic image of highty oriented pyrotytic graphite (HOPG)has been taken using the prepared tip.展开更多
Scanning electrochemical microscopy (SECM) feedback mode has been used to investigate regeneration kinetics on P1 (4-(bis-{4-[5-(2,2-dicyanovinyl) thiophene-2-yl] pH-enyl} amino) benzoic acid) dye sensitized nickel ox...Scanning electrochemical microscopy (SECM) feedback mode has been used to investigate regeneration kinetics on P1 (4-(bis-{4-[5-(2,2-dicyanovinyl) thiophene-2-yl] pH-enyl} amino) benzoic acid) dye sensitized nickel oxide (NiO) electrodes in contact with reduced iodide liquid electrolyte in different electrolyte solvents. We were used acetonitrile, ethanol, methanol and propylene carbonate solvents for comparison under illumination of different wavelengths. We found significant variation of regeneration kinetics parameters such as regeneration rate constant (<em>k<sub>eff</sub></em>), the reduction rate constant (<em>k<sub>red</sub></em>) and absorption cross-section (Φhv) in different illumination intensity and different solvents.展开更多
The components of proton exchange membrane water electrolysers frequently experience corrosion issues, especially at high anodic polarization, that restrict the use of more affordable alternatives to titanium. Here, w...The components of proton exchange membrane water electrolysers frequently experience corrosion issues, especially at high anodic polarization, that restrict the use of more affordable alternatives to titanium. Here, we investigate localized corrosion processes of bare and Ti-coated AISI 446 ferritic stainless steel under anodic polarization by scanning electrochemical microscopy (SECM) in sodium sulphate and potassium chloride solutions. SECM approach curves and area scans measured at open-circuit potential (OCP) of the samples in the feedback mode using a redox mediator evidence a negative feedback effect caused by the surface passive film. For the anodic polarization of the sample, the substrate generation-tip collection mode enables to observe local generation of iron (II) ions, as well as formation of molecular oxygen. For the uncoated AISI 446 sample, localized corrosion is detected in sodium sulphate solution simultaneously with oxygen formation at anodic potentials of 1.0 V vs. Ag/AgCl, whereas significant pitting corrosion is observed even at 0.2 V vs. Ag/AgCl in potassium chloride solution. The Ti-coated AISI 446 sample reveals enhanced corrosion resistance in both test solutions, without any evidence of iron (II) ions generation at anodic potentials of 1.2 V vs. Ag/AgCl, where only oxygen formation is observed.展开更多
MXene,a family of two-dimensional(2D)transition metal carbides and nitrides,has intriguing electrochemical energy storage and electrocatalysis applications.Introducing the electronic metal-support interaction(EMSI)eff...MXene,a family of two-dimensional(2D)transition metal carbides and nitrides,has intriguing electrochemical energy storage and electrocatalysis applications.Introducing the electronic metal-support interaction(EMSI)effect is one effective strategy to optimize the catalytic efficiency for MXene-based composites.However,most of the studies concentrate on optimizing the performance of metals rather than supported substrates by using this strategy.In this work,we mainly investigate the influence of an EMSI effect on the performance of the supported substrate(Ti_(3)C_(2)T_(x)MXene).Detailed scanning electrochemical microscopy and numerical simulations results reveal that the charge distribution on the Ti_(3)C_(2)T_(x)basal plane(approximate 100 nm-radius)surrounding Au nanoparticles(20 nm-radius)was significantly enhanced as a result of-O being the majority surface functional group on Ti_(3)C_(2)T_(x)that was attached to Au nanoparticle,and the related hydrogen evolution reaction(HER)activity was much better than that of the unaffected Ti_(3)C_(2)T_(x)basal plane,which even can be comparable to that of Au.This finding will be helpful for designing new strategies to enhance the overall catalytic performance of various MXene-based composites.展开更多
The influence of sodium silicate on the corrosion behaviour of aluminium alloy 7075-T6 in 0.1 M sodium chloride solution was studied by open circuit potential (OCP) and electrochemical impedance spectroscopy (EIS) tec...The influence of sodium silicate on the corrosion behaviour of aluminium alloy 7075-T6 in 0.1 M sodium chloride solution was studied by open circuit potential (OCP) and electrochemical impedance spectroscopy (EIS) techniques. Scanning electron microscopy (SEM) was used to characterize the AA7075-T6 surface. Silicate can significantly reduce corrosion deterioration and the inhibition efficiency increases with the concentration of Na<sub>2</sub>SiO<sub>3</sub>. The corrosion inhibition mechanism involves the formation of a protective film over the alloy surface by adsorption of aluminosilicate anions from solution, as has also been suggested by others in literature.展开更多
Scanning electrochemical microscopy(SECM)is an attractive technology to in-situ characterize the structural evolution and catalytic performance for various electrocatalysts.However,spatial and temporal resolution coup...Scanning electrochemical microscopy(SECM)is an attractive technology to in-situ characterize the structural evolution and catalytic performance for various electrocatalysts.However,spatial and temporal resolution coupling are still the obstacles that limit its wide applications.Herein,a new operation mode,Fast Scan mode,was developed by improving the dual-pass scan mode,designing novel hardware structure,and employing thermal drift calibration software to achieve a high spatial and temporal resolution simultaneously.The temporal speed can achieve 4 Hz for a high spatial resolution(less than 30 nm)image.This operation mode was employed to dynamically track the phase transition process of molybdenum disulfide(MoS_(2))over time and characterize the hydrogen evolution reaction(HER)catalytic activity on the edge of semiconducting MoS_(2)quantitatively while minimizing the diffusional broadening effect and total amount of catalytic products generated above the surface.This new approach should be useful for in-situ tracking dynamic electrochemical processes,establishing the structure-activity relationship for structural complex electrocatalysts,and offering a strategy for high-speed scanning with other electrochemical imaging techniques.展开更多
基金supported by a characterization platform for advanced materials funded by the Korea Research Institute of Standards and Science(KRISS-2023-GP2023-0014)the KRISS(Korea Research Institute of Standards and Science)MPI Lab.program。
文摘To address climate change and promote environmental sustainability,electrochemical energy conversion and storage systems emerge as promising alternative to fossil fuels,catering to the escalating demand for energy.Achieving optimal energy efficiency and cost competitiveness in these systems requires the strategic design of electrocatalysts,coupled with a thorough comprehension of the underlying mechanisms and degradation behavior occurring during the electrocatalysis processes.Scanning electrochemical microscopy(SECM),an analytical technique for studying surface electrochemically,stands out as a powerful tool offering electrochemical insights.It possesses remarkable spatiotemporal resolution,enabling the visualization of the localized electrochemical activity and surface topography.This review compiles crucial research findings and recent breakthroughs in electrocatalytic processes utilizing the SECM methodology,specifically focusing on applications in electrolysis,fuel cells,and metal–oxygen batteries within the realm of energy conversion and storage systems.Commencing with an overview of each energy system,the review introduces the fundamental principles of SECM,and aiming to provide new perspectives and broadening the scope of applied research by describing the major research categories within SECM.
基金National Key R&D Program of China (2021YFA1501002)National Natural Science Foundation of China (22132007)。
文摘We report here the in situ electrochemical scanning tunneling microscopy(ECSTM) study of cobalt phthalocyanine(CoPc)-catalyzed O_(2) evolution reaction(OER) and the dynamics of CoPc-O_(2) dissociation.The self-assembled CoPc monolayer is fabricated on Au(111) substrate and resolved by ECSTM in 0.1 M KOH electrolyte.The OH^(-)adsorption on CoPc prior to OER is observed in ECSTM images.During OER,the generated O_(2) adsorbed on Co Pc is observed in the CoPc monolayer.Potential step experiment is employed to monitor the desorption of OER-generated O_(2) from CoPc,which results in the decreasing surface coverage of CoPc-O_(2) with time.The rate constant of O_(2) desorption is evaluated through data fitting.The insights into the dynamics of Co-O_(2) dissociation at the molecular level via in situ imaging help understand the role of Co-O_(2) in oxygen reduction reaction(ORR) and OER.
基金supported by the National Natural Science Foundation of China(No.20275031,20335030)the Teaching and Research Award Program for 0utstanding Young Teachers in Higher Education Institutions of M0E P.R.C.the State Key Laboratory of Electroanalytical Chemistry(SKLEAC),Changchun Institute of Applied Chemistry,Chinese Academy of Sciences and Northwest Normal University,Key laboratory of Gansu ploymer materials.
文摘The thiol-porphyrins were prepared to investigate the effect of spacer length on the gold electrode. These measurements showed that as the length of the spacers increases, the SAMs tend to form highly ordered structures on the gold electrodes. In addition, the structures of the monoalyers vary depending on the even and odd number of the methylene spacers （n）.
基金supported by the National Natural Science Foundation of China (No.50499331)the National Science and Technology Basic Conditional Platform (No.2005DTA10400)
文摘The corrosion behavior of aluminum alloys 1060 and 2A12 in a 10 mM Na2SO4＋5 mM KI solution was investigated by scanning electrochemical microscopy （SECM） and scanning electron microscopy （SEM）. The potential topography and corrosion morphology results show that the potential of the sample surface over the same area changes with the increase of immersion time. The corrosion area becomes large, and the potential becomes more negative. The corrosion potential of the 2A12 alloy surface is lower than that of 1060 aluminum, and 2A12 alloy becomes easily corrosive. This is the reason that preferential dissolution in the boundary region of some intermetallic particles （IMPs） occurs and different dissolution behaviors are associated with different types of IMPs because of different potentials.
文摘The activity of horseradish peroxidase at b-cyclodextrin polymer was imaged by scanning electrochemical microscopy using 3, 3', 5, 5'-tetramethylbenzide and H2O2 as the substrates.
文摘Development of reaction-tailored electrocatalysts is becoming increasingly important as energy and environment are among key issues governing our sustainable future.Electrocatalysts are inherently optimized for application towards reactions of interest in renewable energy,such as those involved in water splitting and artificial photosynthesis,owing to its energy efficiency,simple fabrication,and ease of operation.In this view,it is important to secure logical design principles for the synthesis of electrocatalysts for various reactions of interest,and also understand their catalytic mechanisms in the respective reactions for improvements in further iterations.In this review,we introduce several key methods of scanning electrochemical microscopy(SECM)in its applications towards electrocatalysis.A brief history and a handful of seminal works in the SECM field is introduced in advancing the synthetic designs of electrocatalysts and elucidation of the operating mechanism.New developments in nano-sizing of the electrodes in attempts for improved spatial resolution of SECM is also introduced,and the application of nanoelectrodes towards the investigation of formerly inaccessible single catalytic entities is shared.
基金sponsored by the Defense Advanced Research Project Agency (DARPA) and the Army Research Office and was accomplished under Grant Number W911NF-20-1-0304
文摘Elucidating the structure-activity relationship in electrocatalysis is of fundamental interest for electrochemical energy conversion and storage.However,the heterogeneity in the surface structure of electrocatalysts,including the presence of various facets,poses an analytical challenge in revealing the true structure-activity relationship because the activity is conventionally measured on ensemble,resulting in an averaged activity that cannot be unequivocally associated with a single structural motif.Scanning electrochemical cell microscopy(SECCM)[1]combined with colocalized electron backscatter diffraction(EBSD)offers a direct way to reveal the correlative local electrochemical and structural information.Herein,we measured the hydrogen evolution reaction(HER)activity on Ag and its dependence on the crystal orientation.From the combined EBSD and SECCM mapping,it is found that Ag grains closer to{111}show a higher exchange current density,while those closer to{110}show a lower Tafel slope.The Tafel slope is also found to decrease with the step density increase.The ability to measure the electrocatalytic activity under a high mass-transfer rate allows us to reveal the activity difference at a high current density(up to 200 mA/cm^(2)).The approach reported here can be expanded to other systems to reveal the nature of active sites of electrocatalysis.
文摘his paper covers the electropolymerized polypyrrole doped with p-toluenesul-fonate studied using scanning tunneling microscope. The growth processes of polypyrrole films on the electrode surface were observed. Polypyrrole chain struc-ture with many separated micro-holes of 0. 15 nm diameter at the initial state ofelectropolymerization can be seen from obtained STM images. This structure is ex-tremely similar to the pioneer-proposed ideal structure of polypyrrole chains. Thereexisted some helical structure and simple strands on the electrode surface, which isdue to different existing states of polypyrrole chains on electrode surface. STM ex-periments showed that polypyrrole chains were firstly formed on the electrode sur-face, then, they growed gradually by 3-dimensional mode during slow oxidation toform many separated micro-islands. Finally, a large corrugation area of polymerfilms occurred on the electrodes.
文摘A nover technique for the fabrication of the tip for e tectrochemical scanning tunneting microscopy(ECSTM)is presented. The curvature radius of the fabricated tip is smatter than 1 μM. Faradaic leakage current is tess than 0.1nA in the sotution of 1 mol/L NaCl. The atomic image of highty oriented pyrotytic graphite (HOPG)has been taken using the prepared tip.
文摘Scanning electrochemical microscopy (SECM) feedback mode has been used to investigate regeneration kinetics on P1 (4-(bis-{4-[5-(2,2-dicyanovinyl) thiophene-2-yl] pH-enyl} amino) benzoic acid) dye sensitized nickel oxide (NiO) electrodes in contact with reduced iodide liquid electrolyte in different electrolyte solvents. We were used acetonitrile, ethanol, methanol and propylene carbonate solvents for comparison under illumination of different wavelengths. We found significant variation of regeneration kinetics parameters such as regeneration rate constant (<em>k<sub>eff</sub></em>), the reduction rate constant (<em>k<sub>red</sub></em>) and absorption cross-section (Φhv) in different illumination intensity and different solvents.
基金funding from the EEA Grants 2014-2021,under Project contract No.2/2019 CoDe-PEM(EEA RO-NO-2018-0502).
文摘The components of proton exchange membrane water electrolysers frequently experience corrosion issues, especially at high anodic polarization, that restrict the use of more affordable alternatives to titanium. Here, we investigate localized corrosion processes of bare and Ti-coated AISI 446 ferritic stainless steel under anodic polarization by scanning electrochemical microscopy (SECM) in sodium sulphate and potassium chloride solutions. SECM approach curves and area scans measured at open-circuit potential (OCP) of the samples in the feedback mode using a redox mediator evidence a negative feedback effect caused by the surface passive film. For the anodic polarization of the sample, the substrate generation-tip collection mode enables to observe local generation of iron (II) ions, as well as formation of molecular oxygen. For the uncoated AISI 446 sample, localized corrosion is detected in sodium sulphate solution simultaneously with oxygen formation at anodic potentials of 1.0 V vs. Ag/AgCl, whereas significant pitting corrosion is observed even at 0.2 V vs. Ag/AgCl in potassium chloride solution. The Ti-coated AISI 446 sample reveals enhanced corrosion resistance in both test solutions, without any evidence of iron (II) ions generation at anodic potentials of 1.2 V vs. Ag/AgCl, where only oxygen formation is observed.
基金The support of this work by the National Natural Science Foundation of China(No.22204088)the Natural Science Foundation of Shandong Province(Nos.ZR202103040753 and ZR2020MB063)the Taishan Scholar Program of Shandong Province(No.ts201511027)is gratefully acknowledged.
文摘MXene,a family of two-dimensional(2D)transition metal carbides and nitrides,has intriguing electrochemical energy storage and electrocatalysis applications.Introducing the electronic metal-support interaction(EMSI)effect is one effective strategy to optimize the catalytic efficiency for MXene-based composites.However,most of the studies concentrate on optimizing the performance of metals rather than supported substrates by using this strategy.In this work,we mainly investigate the influence of an EMSI effect on the performance of the supported substrate(Ti_(3)C_(2)T_(x)MXene).Detailed scanning electrochemical microscopy and numerical simulations results reveal that the charge distribution on the Ti_(3)C_(2)T_(x)basal plane(approximate 100 nm-radius)surrounding Au nanoparticles(20 nm-radius)was significantly enhanced as a result of-O being the majority surface functional group on Ti_(3)C_(2)T_(x)that was attached to Au nanoparticle,and the related hydrogen evolution reaction(HER)activity was much better than that of the unaffected Ti_(3)C_(2)T_(x)basal plane,which even can be comparable to that of Au.This finding will be helpful for designing new strategies to enhance the overall catalytic performance of various MXene-based composites.
文摘The influence of sodium silicate on the corrosion behaviour of aluminium alloy 7075-T6 in 0.1 M sodium chloride solution was studied by open circuit potential (OCP) and electrochemical impedance spectroscopy (EIS) techniques. Scanning electron microscopy (SEM) was used to characterize the AA7075-T6 surface. Silicate can significantly reduce corrosion deterioration and the inhibition efficiency increases with the concentration of Na<sub>2</sub>SiO<sub>3</sub>. The corrosion inhibition mechanism involves the formation of a protective film over the alloy surface by adsorption of aluminosilicate anions from solution, as has also been suggested by others in literature.
基金The support of this work by the National Natural Science Foundation of China(No.22204088)the Natural Science Foundation of Shandong Province(Nos.ZR202103040753 and ZR2020MB063)the Taishan Scholar Program of Shandong Province(No.ts201511027)is gratefully acknowledged.
文摘Scanning electrochemical microscopy(SECM)is an attractive technology to in-situ characterize the structural evolution and catalytic performance for various electrocatalysts.However,spatial and temporal resolution coupling are still the obstacles that limit its wide applications.Herein,a new operation mode,Fast Scan mode,was developed by improving the dual-pass scan mode,designing novel hardware structure,and employing thermal drift calibration software to achieve a high spatial and temporal resolution simultaneously.The temporal speed can achieve 4 Hz for a high spatial resolution(less than 30 nm)image.This operation mode was employed to dynamically track the phase transition process of molybdenum disulfide(MoS_(2))over time and characterize the hydrogen evolution reaction(HER)catalytic activity on the edge of semiconducting MoS_(2)quantitatively while minimizing the diffusional broadening effect and total amount of catalytic products generated above the surface.This new approach should be useful for in-situ tracking dynamic electrochemical processes,establishing the structure-activity relationship for structural complex electrocatalysts,and offering a strategy for high-speed scanning with other electrochemical imaging techniques.
