Metal-ion bridged high conductive RGO-M-MoS2 (M = Fe3+, Co2+, Ni2+, Cu2+ and Zn2+) composite electrocatalysts for photo-assisted hydrogen evolution

Efficient photo-electrocatalysts for hydrogen evolution reaction (HER) are synthesized using a facile one-step hydrothermal method. With metal-ion bridges, highly dispersed molybdenum disulfide (MoS 2 ) nanolayers are vertically grown on the reduced graphene oxide (RGO) to form RGO-M-MoS 2 photocatalysts for HER, where M = Fe 3+ , Co 2+ , Ni 2+ , Cu 2+ and Zn 2+ . The results show that the cross-bridging ions can modulate the MoS 2 growth priority and act as efficient charge transfer channels between RGO and MoS 2 , and combine the advantages of the high conductivity of graphene with the photo-electrochemical activity of MoS 2 . The metal-ion bridged MoS 2 -M-RGO heterostructures demonstrate superior catalytic activity toward hydrogen evolution reaction in acid medium, evidenced by the remarkable higher catalytic current density at low overpotential compared with that of MoS 2 -RGO without metal-ion bridge. This study provides a novel and facile route for establishing efficient composite photo-electrocatalysts for water splitting to generate hydrogen.