Developing a low-cost and high-efficiency nonprecious metal-based catalyst for hydrogen evolution reaction(HER) is of great significance for the utilization of hydrogen energy.In this work,we report a molecular-modifi...Developing a low-cost and high-efficiency nonprecious metal-based catalyst for hydrogen evolution reaction(HER) is of great significance for the utilization of hydrogen energy.In this work,we report a molecular-modification strategy to fabricate a self-supported hydrogen evolution electrode,specially by grafting the macrocyclic molecules(HHTP=2,3,6,7,10,11-hexahydroxytriphenylene) on the surface of a cobaltous dihydroxy carbonate(COC) seed layer.The HHTP-COC electrode is endowed with a rodlike structure,which provides favorable access for charge transportation and mass exchange.The macrocyclic molecule structure in HHTP can be grafted on COC and improve the electrical conductivity,while the interaction between HHTP and COC induces the rearrangement of charge configuration on the surface.Due to the combination effects of several aspects,the HHTP-COC electrode achieves astonishing HER activity,with a low overpotential of 61.0 mV(η_(10),at the current density of 10 mA cm^(-2)) and excellent stability in alkaline condition.This kind of interface engineering based on the organic molecules can be applied to the design and manufacture of electrocatalysts in the field of energy conversion and storage.展开更多
Interfacial electron transfer governs electrochemical heterogeneity at the single-entity level.Herein,we investigated the electronic coupling event during electrodissolution processes of single silver nanoentities on ...Interfacial electron transfer governs electrochemical heterogeneity at the single-entity level.Herein,we investigated the electronic coupling event during electrodissolution processes of single silver nanoentities on a Au electrode through a synchronized electrochemical-optical tracking platform.By implementing strategic control of interfacial gap distances and electrolyte composition,a marked differentiation of single-particle reaction dynamics can be achieved.The integration of superlocalization methodology reveals position-correlated optical centroid shifts during electrodissolution processes,demonstrating heterogeneous oxidation dynamics arising from spatially nonuniform surface oxide formation.Crucially,SAMmediated gap regulation enables the precise regulation of interfacial electric field enhancement.Our methodology resolves electronic coupling heterogeneity at subnanowire scale while proving molecular interlayer-dependent modulation of coupling lifetimes.This electrochemical-optical imaging strategy establishes nanoscale spatial mapping of electrochemical dynamics,quantitative correlation between interfacial structure and coupling efficiency,and real-time tracking of transient electronic states.These findings demonstrate the capability of advanced optical imaging methodologies in elucidating structure−activity relationships at nanoscale interfaces,providing mechanistic insights for single-entity electrochemistry and nanoscale energy conversion systems.展开更多
Printing is a method of additive manufacturing that can reduce material costs and environmental contamination during the fabrication process.Ag ink is commonly used in printed electronics,such as interconnects,inducto...Printing is a method of additive manufacturing that can reduce material costs and environmental contamination during the fabrication process.Ag ink is commonly used in printed electronics,such as interconnects,inductors,and antennas.However,the high cost of noble Ag restricts its massive applications.To reduce the cost of the state-of-the-art Ag ink and realize large-scale manufacturing,we develop a molecule-bridged graphene/Ag(MB-G/A)composite to produce highly conductive and cost-effective paperbased electronics.Graphene can be used to substitute part of Ag nanoparticles to reduce costs,form a conducive percolation network,and retain a reasonable level of conductivity.We adopt cysteamine as a molecular linker,because it anchors on the surface of graphene via the diazonium reaction.Additionally,the thiol functional group on the other end of cysteamine can bond to a Ag atom,forming a molecular bridge between graphene and Ag and promoting electron transport between Ag and graphene.As a result,the maximum conductivity of MB-G/A inks can reach 2.0×10^(5)S m^(−1),enabling their successful application in various printable electronics.In addition,the optimum MB-G/A ink costs less than half as much as pure Ag inks,showing the great potential of MB-G/A ink in commercial electronic devices.展开更多
基金funded by grants from the National Natural Science Foundation of China (21771101, 52201258)the Natural Science Foundation of Jiangsu Province, China (BK20210651 and BK20210650)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China (21KJB430003)。
文摘Developing a low-cost and high-efficiency nonprecious metal-based catalyst for hydrogen evolution reaction(HER) is of great significance for the utilization of hydrogen energy.In this work,we report a molecular-modification strategy to fabricate a self-supported hydrogen evolution electrode,specially by grafting the macrocyclic molecules(HHTP=2,3,6,7,10,11-hexahydroxytriphenylene) on the surface of a cobaltous dihydroxy carbonate(COC) seed layer.The HHTP-COC electrode is endowed with a rodlike structure,which provides favorable access for charge transportation and mass exchange.The macrocyclic molecule structure in HHTP can be grafted on COC and improve the electrical conductivity,while the interaction between HHTP and COC induces the rearrangement of charge configuration on the surface.Due to the combination effects of several aspects,the HHTP-COC electrode achieves astonishing HER activity,with a low overpotential of 61.0 mV(η_(10),at the current density of 10 mA cm^(-2)) and excellent stability in alkaline condition.This kind of interface engineering based on the organic molecules can be applied to the design and manufacture of electrocatalysts in the field of energy conversion and storage.
基金National Natural Science Foundation of China(NSFC,Grant Number:22222406,22174062).
文摘Interfacial electron transfer governs electrochemical heterogeneity at the single-entity level.Herein,we investigated the electronic coupling event during electrodissolution processes of single silver nanoentities on a Au electrode through a synchronized electrochemical-optical tracking platform.By implementing strategic control of interfacial gap distances and electrolyte composition,a marked differentiation of single-particle reaction dynamics can be achieved.The integration of superlocalization methodology reveals position-correlated optical centroid shifts during electrodissolution processes,demonstrating heterogeneous oxidation dynamics arising from spatially nonuniform surface oxide formation.Crucially,SAMmediated gap regulation enables the precise regulation of interfacial electric field enhancement.Our methodology resolves electronic coupling heterogeneity at subnanowire scale while proving molecular interlayer-dependent modulation of coupling lifetimes.This electrochemical-optical imaging strategy establishes nanoscale spatial mapping of electrochemical dynamics,quantitative correlation between interfacial structure and coupling efficiency,and real-time tracking of transient electronic states.These findings demonstrate the capability of advanced optical imaging methodologies in elucidating structure−activity relationships at nanoscale interfaces,providing mechanistic insights for single-entity electrochemistry and nanoscale energy conversion systems.
基金financially supported by Hong Kong Scholars Program(XJ2019025)The Hong Kong Polytechnic University(CD42)Shenzhen Science and Technology Innovation Commission(JCYJ20180507183424383)。
文摘Printing is a method of additive manufacturing that can reduce material costs and environmental contamination during the fabrication process.Ag ink is commonly used in printed electronics,such as interconnects,inductors,and antennas.However,the high cost of noble Ag restricts its massive applications.To reduce the cost of the state-of-the-art Ag ink and realize large-scale manufacturing,we develop a molecule-bridged graphene/Ag(MB-G/A)composite to produce highly conductive and cost-effective paperbased electronics.Graphene can be used to substitute part of Ag nanoparticles to reduce costs,form a conducive percolation network,and retain a reasonable level of conductivity.We adopt cysteamine as a molecular linker,because it anchors on the surface of graphene via the diazonium reaction.Additionally,the thiol functional group on the other end of cysteamine can bond to a Ag atom,forming a molecular bridge between graphene and Ag and promoting electron transport between Ag and graphene.As a result,the maximum conductivity of MB-G/A inks can reach 2.0×10^(5)S m^(−1),enabling their successful application in various printable electronics.In addition,the optimum MB-G/A ink costs less than half as much as pure Ag inks,showing the great potential of MB-G/A ink in commercial electronic devices.
