Hydrangea like composite catalysts of ultrathin Mo2S3 nanosheets assembled on N, S-dual-doped graphitic biocarbon spheres with highly electrocatalytic activity for HER.

Water electrolysis is the most clean and high-efficiency technology for production of hydrogen, an ultimate clean energy in future. Highly efficient non-noble electrocatalysts for hydrogen evolution reaction (HER) are desirable for large scale production of hydrogen by water electrolysis. Especially, exposing as many active sites as possible is a vital way to improve activities of the catalysts. Herein, a series of new hydrangea like composite catalysts of ultrathin Mo 2 S 3 nanosheets assembled uprightly and interlacedly on N, S-dual-doped graphitic biocarbon spheres were facilely prepared. The unique structure endowed the catalysts highly exposed edge active sites and prominently high activities for HER. Especially, the optimized catalyst Mo 2 S 3 /NSCS-50 exhibited as low as 106 mV of overpotential at 10 mA/cm2 (denoted as ƞ 10). The catalyst also showed low Tafel slope of 53 mV/dec, low electron transfer resistance of 34 Ω and high stability evidenced by the result that the current density only attenuated 11.7% after 10 h i-t test. The catalyst has shown broad prospect for commercial application in water electrolysis. • New Mo 2 S 3 ultrathin nanosheets based catalysts have been fabricated for HER. • Mo 2 S 3 ultrathin nanosheets assembled uprightly and interlacedly on carbon spheres. • Hydrangea like composite catalysts were formed based on the above assembly. • The unique structure can provide plenty of exposed edge active sites. • The catalysts exhibited prominent activities and high stabilities for HER. [ABSTRACT FROM AUTHOR]