Nano-netlike carbon fibers decorated with highly dispersed CoSe2 nanoparticles as efficient hydrogen evolution electrocatalysts

Abstract More active sites and high conductivity are two effective ways to improve the activity of non-noble metal electrocatalysts. Herein, we present a facile electrostatic spinning technique to synthesize highly dispersed CoSe 2 nanoparticles on three-dimensional nano-netlike carbon fibers through simple thermal treatment of polyacrylonitrile fibers containing Co ions (Co 2+ -PANF) and subsequent in-situ selenization. Moreover, we show that the resulting material (denoted as CoSe 2 -CFN) can serve as highly active, efficient and stable non-precious metal electrocatalyst for HER in acidic media. This material achieves a current density of 10 mA/cm 2 at an overpotential of 133 mV with a loading amount of the active material CoSe 2 about 0.128 mg/cm 2 , which is lower than that of the reported CoSe 2 -based materials. Meanwhile, CoSe 2 -CFN exhibits excellent catalytic stability for at least 20 h and gives nearly 100% Faradaic yield. The excellent hydrogen evolution reaction performance is due to the highly dispersed CoSe 2 nanoparticles providing more active sites as well as the high electrical conductivity of the carbon fibers.