An efficient CoS2/CoSe2 hybrid catalyst for electrocatalytic hydrogen evolution

Herein we established a robust and highly efficient catalyst for the hydrogen evolution reaction (HER), with the characteristic of CoS2 nanoparticles dotted on the surface of CoSe2/DETA (DETA = diethylenetriamine) nanobelts (CoS2/CoSe2). The CoSe2/DETA nanobelts possess intrinsic high conductivity and superior electrocatalytic activity. In addition, the evenly distributed amino groups on the surfaces of CoSe2/DETA nanobelts contribute to copious nucleation sites, which are in favor of easy nucleation, uniform dispersion, and size control of CoS2 nanoparticles. Owing to the prominent synergistic effect between CoS2 nanoparticles and CoSe2 nanobelts, the CoS2/CoSe2 hybrid exhibits a superior HER activity with a small overpotential of 80 mV at a cathodic current density of 10 mA cm(-2), and a small Tafel slope of 33.6 mV dec(-1) in acidic media. Meanwhile, the catalyst shows excellent mechanical stability.