P-doped 3D graphene network supporting uniformly vertical MoS2 nanosheets for enhanced hydrogen evolution reaction

In order to optimize the conductivity of molybdenum disulfide (MoS 2 ) and promote its large-scale application as a catalyst for hydrogen evolution , MoS 2 is usually used to form composites with conductive materials , but these hybrid materials suffer from scare active sites, overlapping and complicate process. In this work, phosphoric acid is used as a builder of stereoscopic structures, which can not only twist graphene sheets into a P-doped three-dimensional (3D) graphene network but also promote surface electron transport between graphene sheets. Without adding additional framework materials such as carbon nanotubes or nickel foam, stereoscopic MoS 2 /graphene structures are formed with a large number of twisted graphene sheets to support the vertical growth of MoS 2 and expose the edge sites of MoS 2 , showing a low Tafel slope about 35 mV dec −1 , a high current density of 900 mA cm −2 at about 300 mV and a robust stability over 2000 cycles. Thus, this work shows a possibility to synthesize an efficient catalyst on a large-scale for hydrogen evolution reaction, which can promote the realization of hydrogen economy .