Nickel and Molybdenum Composites Decorated Nitrogen-Doped Carbon Catalysts from Spent Coffee Grounds for Alkaline Hydrogen Evolution.

Biomass-derived materials can help develop efficient, environmentally friendly and cost-effective catalysts, thereby improving the sustainability of hydrogen production. Herein, we propose a simple method to produce nickel and molybdenum composites decorated spent coffee grounds (SCG) as an efficient catalyst, SCG(200)@NiMo, for electrocatalytic hydrogen production. The porous carbon supporter derived form SCG provided a larger surface, prevented aggregation during the high temperature pyrolysis, optimized the electronic structure by N and provided a reducing atmosphere for the oxides reduction to form heterojunctions. The sieved SCG showed obvious improvement of HER performance and enhanced conductivity and long-term durability. The obtained SCG(200)@NiMo exhibits the highest electrochemical performance for the hydrogen evolution reaction process, as evidenced by the overpotential of only 127 mV at a current density of ɳ and 97.7 % catalytic activity retention even after 12 h of operation. This work may stimulate further exploration of efficient electrocatalysts derived from biomass.