W 2 N/WC composite nanofibers as an efficient electrocatalyst for photoelectrochemical hydrogen evolution.

A tungsten-based electrocatalyst for hydrogen evolution reaction is vital for developing sustainable and clean energy sources. Herein, W 2 N/WC composite nanofibers were synthesized through electrospinning technology and simultaneous carbonization and N-doping at high temperature. The composite nanofiber has higher catalytic activity than any simple compound. It exhibits remarkable hydrogen evolution performance in acidic media with a low overpotential of -495 mV, at a current density of -50 mA cm -2 . The excellent hydrogen evolution performance of the composite nanofiber could be attributed to the abundant active sites, strong light absorption and fast charge transfer. The method used in this work provides a new possibility for the fabrication of high-performance electrocatalysts rationally.