Transition metal nitrides(TMNs)are considered as viable alternatives to noble metal catalysts owing to their versatile electronic structure and favorable catalytic performance.However,the conventional synthetic proces...Transition metal nitrides(TMNs)are considered as viable alternatives to noble metal catalysts owing to their versatile electronic structure and favorable catalytic performance.However,the conventional synthetic processes for TMNs suffer from high energy consumption and low production yield.In this study,a range of TMNs and their hetero-composite arrays were successfully synthesized via an ultrafast flash Joule heating technology within 0.5 s.As a proof concept,the nitrides and hetero-composites were applied for the electrocatalytic hydrazine oxidation reaction(HzOR),in which the Co_(4)N/Mo_(16)N_(7)arrays shows the best performance with a geometric current density of 100 mA cm^(-2)at 23 mV(vs.reversible hydrogen electrode(RHE)).This work paves a new way for the ultrafast synthesis of TMNs which could meet the ever-increased energy crisis.展开更多
The origin of superconductivity observed at the point contact between the normal metal tip and the topological material remains uncertain due to the potential presence of superconducting elements or allotropes impurit...The origin of superconductivity observed at the point contact between the normal metal tip and the topological material remains uncertain due to the potential presence of superconducting elements or allotropes impurities.It is imperative to seek out a topological material entirely free of superconducting impurities and induce superconductivity between it and normal tips to verify the source of the induced superconductivity.Here,we report the observation of superconductivity up to 9 K induced at point contacts between normal metal tips and the topological material grey arsenic,which is free of superconductivity.The determined temperature dependencies of superconducting gapsΔ(T)deviate from the Bardeen-Cooper-Schriefer(BCS)superconductivity law,exhibiting abnormal behavior.Furthermore,the highly anisotropic upper critical field H_(c2)(T)suggests the anisotropy of the projected interfacial Fermi surface.By tuning the junction resistance,we obtained a negative correlation between the superconducting gapΔand the efective barrier height Z,which validates the interfacial coupling strength as a key factor in the observed tip-induced superconductivity.These experimental results provide guidance for the relevant theory about tip-induced superconductivity on topological materials.展开更多
基金supported by the National Natural Science Foundation of China(22375001)the Natural Science Foundation of Anhui Province(2208085Y03,2208085QB30)+2 种基金the University Synergy Innovation Program of Anhui Province(GXXT-2023-036)the Key Scientific Research Foundation of the Education Department of Anhui Province(2023AH050113)the Start-up Grant from Anhui University。
文摘Transition metal nitrides(TMNs)are considered as viable alternatives to noble metal catalysts owing to their versatile electronic structure and favorable catalytic performance.However,the conventional synthetic processes for TMNs suffer from high energy consumption and low production yield.In this study,a range of TMNs and their hetero-composite arrays were successfully synthesized via an ultrafast flash Joule heating technology within 0.5 s.As a proof concept,the nitrides and hetero-composites were applied for the electrocatalytic hydrazine oxidation reaction(HzOR),in which the Co_(4)N/Mo_(16)N_(7)arrays shows the best performance with a geometric current density of 100 mA cm^(-2)at 23 mV(vs.reversible hydrogen electrode(RHE)).This work paves a new way for the ultrafast synthesis of TMNs which could meet the ever-increased energy crisis.
基金supported by the National Natural Science Foundation of China(51972001,52103111,and 22005002)the Natural Science Fund of Education Department of Anhui Province(KJ2019A0013)+4 种基金Changjiang Scholars and Innovative Research Team in UniversityAnhui University Scientific Research Start-up Fund(S020318006/005 and S020318008/026)the Key Lab of Photovoltaic and Energy Conservation Materials,Chinese Academy of Sciences(PECL2019KF012)Anhui Province Educational Quality Engineering Foundation Program(2020xfxm67)the Natural Science Foundation of Anhui Educational Committee(KJHS2021B11 and KJ2021ZD0121)。
基金supported by the National Key R&D Program of China(Grant Nos.2022YFA1403203,2017YFA0302904,2017YFA0303201,2018YFA0305602,and 2016YFA0300604)the National Natural Science Foundation of China(Grant Nos.12074002,11574372,11674331,11804379,11874417,and 92265104)+4 种基金the National Basic Research Program of China(Grant No.2015CB921303)the“Strategic Priority Research Program(B)”of the Chinese Academy of Sciences(Grant Nos.XDB07020300,XDB07020100,and XDB33030100)the Recruitment Program for Leading Talent Team of Anhui Province(2019-16)the Major Basic Program of Natural Science Foundation of Shandong Province(Grant No.ZR2021ZD01)supported by the High Magnetic Field Laboratory of Anhui Province,China。
文摘The origin of superconductivity observed at the point contact between the normal metal tip and the topological material remains uncertain due to the potential presence of superconducting elements or allotropes impurities.It is imperative to seek out a topological material entirely free of superconducting impurities and induce superconductivity between it and normal tips to verify the source of the induced superconductivity.Here,we report the observation of superconductivity up to 9 K induced at point contacts between normal metal tips and the topological material grey arsenic,which is free of superconductivity.The determined temperature dependencies of superconducting gapsΔ(T)deviate from the Bardeen-Cooper-Schriefer(BCS)superconductivity law,exhibiting abnormal behavior.Furthermore,the highly anisotropic upper critical field H_(c2)(T)suggests the anisotropy of the projected interfacial Fermi surface.By tuning the junction resistance,we obtained a negative correlation between the superconducting gapΔand the efective barrier height Z,which validates the interfacial coupling strength as a key factor in the observed tip-induced superconductivity.These experimental results provide guidance for the relevant theory about tip-induced superconductivity on topological materials.
