Abstract
The density functional theory(DFT)calculations have been performed to investigate the catalytic prop-erties of monolayer MoSi2N4 for hydrogen evolution reaction(HER).The DFT results show that similar to the majority of other two-dimensional(2D)materials,the pristine MoSi2N4 is inert for HER due to its weak affinity toward hydrogen,while monolayer MoSi2N4-x(x=0-0.25)exhibits the highly desirable HER catalytic activities by introducing surface nitrogen vacancy(NV).The predicted HER overpotential(0-60 mV)of monolayer MoSi2N4-x is lower than that(90 mV)of noble metal Pt,when the concentra-tion of surface NV is lower than 5.6％.Electronic structure calculations show that the spin-polarized states appear around the Fermi level after introducing surface NV,thus making the surface NV on 2D MoSi2N4 a quite suitable site for HER.Moreover,the HER activity of MoSi2N4-x is highly dependent on the surface NV concentration,which can be further related to the center of Si-3p band.Our results demonstrate that the newly discovered 2D MoSi2N4 can be served as a promising electrocatalyst for HER via appropriate defect engineering.
基金项目
National Natural Science Founda-tion of China(51972312)
National Natural Science Founda-tion of China(51472249)
NETL
NSTL
万方数据