Nanocarbon encapsulating Ni-doped MoP/graphene composites for highly improved electrocatalytic hydrogen evolution reaction

Abstract

Rationally designing highly efficient, stable and earth-abundant electrocatalysts plays a leading role for hydrogen evolution reaction (HER) from water splitting but is still challenging. The development of well-defined transition metal-based nanostructures for enhancing the HER activity and stability has sparked great interests in electrocatalysis. Herein, we report the in-situ synthesis of novel hybrid nanoarchitectures of Ni-doped MoP/reduced graphene oxide (NM/rGO) for high-performance electrocatalysis toward HER. Under the dual regulation on the composition and the interfacial interactions, the well-organized 0D/2D nanohybrids exhibited better electrocatalytic activity and enhanced stability for HER than those of Ni-doped MoP nanoparticles. The optimal hybrid electrocatalyst (NM/rGO-2:1) showed an overpotential of 122 mV at current density of 10 mA cm−2 and its corresponding Tafel slope was 71.4 mV dec−1 in alkaline electrolyte. The synergy of well-dispersed Ni–MoP nanoparticles with smaller sizes and highly conductive rGO nanosheets resulted in rich active catalytic sites that remarkably boosted electrocatalytic HER performance. This work may broaden the possibility of exploiting a new family of non-precious metal-based electrocatalysts toward HER.