Promoting the intrinsic catalytic activity of transition metal dichalcogenides(TMDs)for the hydrogen evolution reaction(HER)is very beneficial for developing Pt-free single-component electrocatalysts.Here we report a ...Promoting the intrinsic catalytic activity of transition metal dichalcogenides(TMDs)for the hydrogen evolution reaction(HER)is very beneficial for developing Pt-free single-component electrocatalysts.Here we report a single-component TMD-based electrocatalyst,Cu_(0.4)NbS_(2−δ),with chemical intercalation and sulfur vacancies.Cu_(0.4)NbS_(2−δ)was synthesized conveniently using a solid-phase reaction and it exhibits a hexagonal lattice with intercalated Cu atoms in a four-coordinated tetrahedral configuration.Comprehensive experiments and theoretical calculations indicate that the intercalation and S vacancies redistributed the electronic structure of pristine NbS_(2),leading to multi-functional catalytic sites including defect hollow sites in the basal plane and different Cu sites in between the layers.Therefore,hydrogen spillover can proceed along pathways at the atomic level in Cu_(0.4)NbS_(2−δ)from proton adsorption at defect hollow sites,through interlayer sites for readily occurring hydrogen migration,and finally to Cu sites for fast H_(2)desorption.Based on this atomic-scale hydrogen spillover effect,the polycrystalline Cu_(0.4)NbS_(2−δ)exhibits a low overpotential of 153 mV at 10 mA cm^(-2)and great durability after 3000 cycles.Our work provides an effective strategy to build hydrogen spillover pathways in TMDs,which is instructive for exploring economical single-component electrocatalysts with high intrinsic activity.展开更多
基金National Natural Science Foundation of China(no.52271199 and 51832010)National Key R&D Program of China(no.2020YFA0406202)+1 种基金Fundamental Research Funds for the Central Universities(FRF-EYIT-23-04)Open Fund of State Key Laboratory of Advanced Metallurgy(KF21-01)。
文摘Promoting the intrinsic catalytic activity of transition metal dichalcogenides(TMDs)for the hydrogen evolution reaction(HER)is very beneficial for developing Pt-free single-component electrocatalysts.Here we report a single-component TMD-based electrocatalyst,Cu_(0.4)NbS_(2−δ),with chemical intercalation and sulfur vacancies.Cu_(0.4)NbS_(2−δ)was synthesized conveniently using a solid-phase reaction and it exhibits a hexagonal lattice with intercalated Cu atoms in a four-coordinated tetrahedral configuration.Comprehensive experiments and theoretical calculations indicate that the intercalation and S vacancies redistributed the electronic structure of pristine NbS_(2),leading to multi-functional catalytic sites including defect hollow sites in the basal plane and different Cu sites in between the layers.Therefore,hydrogen spillover can proceed along pathways at the atomic level in Cu_(0.4)NbS_(2−δ)from proton adsorption at defect hollow sites,through interlayer sites for readily occurring hydrogen migration,and finally to Cu sites for fast H_(2)desorption.Based on this atomic-scale hydrogen spillover effect,the polycrystalline Cu_(0.4)NbS_(2−δ)exhibits a low overpotential of 153 mV at 10 mA cm^(-2)and great durability after 3000 cycles.Our work provides an effective strategy to build hydrogen spillover pathways in TMDs,which is instructive for exploring economical single-component electrocatalysts with high intrinsic activity.
