Ni_(2)P/MoS_(2) interfacial structures loading on N-doped carbon matrix for highly efficient hydrogen evolution

Electrochemical catalysts for the hydrogen evolution reaction(HER) have attracted increasing attentions. Noble metal-free cocatalysts play a vital role in HER applications. Herein, a novel strategy to prepare a Ni_(2)P/MoS_(2) cocatalyst through a simple hydrothermal-phosphorization method was reported, and the prepared cocatalyst was then loaded on an N-doped carbon substrate with excellent conductive performance. The large surface area of the carbon substrate provided many active sites, and the interface between Ni_(2)P and MoS_(2) improved the catalytic performance for the HER. Compared with pure Ni_(2)P catalyst and MoS_(2) catalyst, the prepared Ni_(2)P/MoS_(2) cocatalyst exhibited enhanced catalytic performance. In addition, the results indicate that the prepared cocatalyst has a wide p H range and low onset potential values of 280, 350 and40 m V in acidic, phosphate-buffered saline and alkaline solutions, respectively, and the corresponding Tafel slopes are 75, 121 and 95 mV dec^(-1),respectively. Density functional theory(DFT) was adopted to calculate the hydrogen adsorption free energy(ΔG_(H)^(*)). The results showed that the interface between Ni_(2)P and MoS_(2) reduced ΔG_H^(*), which was beneficial to the adsorption of hydrogen. Present preparation of cocatalysts with unique interfaces provides a new strategy for improving the catalytic performance of HER.