Ni–Fe layered double hydroxide nanosheets immobilized on three-dimensional crosslinked MoS2-graphene architectures for efficient electrocatalytic hydrogen evolution

Abstract

Two-dimensional layered double hydroxide (LDH) nanosheets are regarded as promising cathode catalysts toward the hydrogen evolution reaction (HER), while their overall electrocatalytic capability remains to be optimized before practical application. Herein, we demonstrate a robust bottom-up approach to fabricate ultrathin Ni–Fe LDHs immobilized on three-dimensional crosslinked architectures built from MoS2 nanosheets and graphene (LDH/MoS2-G) through a convenient and cost-effective co-assembly process. This unique structural design is able to acquire a series of textural merits, such as three-dimensional interconnected frameworks with ultrathin walls, abundant porous channels, large accessible surface areas, optimized electronic structures, and high electric conductivity, which can effectively accelerate the electrochemical kinetics during the HER process. Consequently, the resulting LDH/MoS2-G architectures exhibit an exceptional HER performance with a low onset potential, a small Tafel slope, and a long lifespan in the alkaline medium, more competitive than that of bare LDH, MoS2, graphene as well as binary LDH/graphene and MoS2/graphene electrocatalysts.