Molybdenum Disulfide-Black Phosphorus Hybrid Nanosheets as a Superior Catalyst for Electrochemical Hydrogen Evolution

Engineering electronic properties is a promising way to design nonprecious-metal or earth-abundant catalysts toward hydrogen evolution reaction (HER). Herein, we deposited catalytically active MoS2 flakes onto black phosphorus (BP) nanosheets to construct the MoS2-BP interfaces. In this case, electrons flew from BP to MoS2 in MoS2-BP nanosheets because of the higher Fermi level of BP than that of MoS2. MoS2-BP nanosheets exhibited remarkable HER performance with an overpotential of 85 mV at 10 mA cm(-2). Due to the electron donation from BP to MoS2, the exchange current density of MoS2-BP reached 0.66 mA cm 2, which was 22 times higher than that of MoS2. In addition, both the consecutive cyclic voltammetry and potentiostatic tests revealed the outstanding electrocatalytic stability of MoS2-BP nanosheets. Our finding not only provides a superior HER catalyst, but also presents a straightforward strategy to design hybrid electrocatalysts.