The Study Of Tungsten-based Nitride Electrocatalyst By Doping For Highly-efficient Hydrogen Evolution Reaction

The increasing consumption of fossil fuel is considered to be the main cause of global warming and environmental pollution.The development of clean and renewable energy is a promising approach to conquer these serious problems.However,the most abundant renewable energy sources are difficult to use effectively due to their intermittent feature.Electrocatalytic hydrogen evolution technology to convert the electric energy generated by renewable energy into clean hydrogen energy is an ideal way.But high cost precious metal（such as Pt and alloy）catalysts restrict their large-scale application.Therefore,much efforts have been made to develop abundant,low cost and efficient non-precious metal catalysts,such as transition metal nitride and phosphide,have attracted much attention.However,these catalysts exhibit low intrinsic catalytic performance.In this paper,heteroatom doping was used to improve the electrocatalytic performance of tungsten based catalyst for hydrogen evolution.The main research contents are as follows:（1）WO₃ nanowire arrays（NWs）were prepared on carbon cloth by hydrothermal method.After nitridation treatment in NH3 ambient,the WN NWs were obtained,then the P doped WN NWs（P/WN NWs）were fabircated by phosphating treatment.P/WN NWs have a porous structure and P species uniformly distribute throughout the NW.The results show that P doping reduces the resistivity of WN,and promote the adsorption and conversion of active hydrogen,which enhances the electrocatalytic activity and stability of WN,such as an overpotential（η10）of 196,194 and 285 mV with Tafel slope of 114,93 and 139 mV dec-1 in alkaline,acidic solution,and neutral media as well as the excellent stability with 93%voltage retention after 12 h testing.（2）Cobalt-doped WO₃ NWs were grown on carbon cloth by hydrothermal method,and then Co,P co-doped WN NWs（Co-P/WN NWs）was obtained by subsequently nitriding and phosphating.The results show that Co and P are uniformly distributed in WN NWs,further reduces the resistance of WN or P/WN,optimizes the site activity and improves the reaction kinetics,exhibiting excellent HER performance in a wide pH range,such as an overpotential（η10）of 114,134 and 131 mV and Tafel slope of 64,73 and 79 mV dec-1 in alkaline,acidic and neutral media,as well as superior stability.