Carbon-coated MoS2 nanosheets as highly efficient electrocatalysts for the hydrogen evolution reaction.

As a green and highly efficient energy resource, hydrogen (H2) has attracted much attention in recent years. Electrochemical water splitting is an economic process to generate H2. MoS2 is a promising candidate to replace traditional Pt-based electrocatalysts for the hydrogen evolution reaction (HER) under acidic conditions. But low electrical conductivity is one of bottlenecks for the large-scale application of MoS2. In this work, a carbon-coated MoS2 hybrid electrocatalyst was prepared with a chemical vapour deposition (CVD) approach to improve the electrical conductivity of MoS2. In addition to the surface-coating carbon, a small graphene-like layer could also be inserted into the interlayers of MoS2 during the CVD process which resulted in more active sites being exposed in MoS2. Enhanced electrical conductivity and more exposed active sites lead to excellent HER activity.