N, P dual-doped hollow carbon spheres supported MoS2 hybrid electrocatalyst for enhanced hydrogen evolution reaction
By Chi, Jing-Qi; Gao, Wen-Kun; Lin, Jia-Hui; Dong, Bin; Yan, Kai-Li; Qin, Jun-Feng; Liu, Bin; Chai, Yong-Ming; Liu, Chen-Guang
Published in Catalysis Today
2019
Abstract
The ultrathin MoS2 nanosheets-coated N, P dual-doped hollow carbon nanospheres (NPC@MoS2) have been synthesized through a facile template sacrificial method to prepare P-promoted enlarged hollow carbon spheres with followed solvothermal process. P doping in NC can not only tune the electron configuration but also promote formation of hollow nanospheres with larger voids compared with NC. The key to producing carbon spheres with larger voids can be ascribed to the rapid oxidation of P species at high temperature, which provides a strong driving force for the outward diffusion of P. Through optimizing the amount of Mo source, the as-prepared NPC@MoS2 with medium amount of Mo source have demonstrated outstanding hydrogen evolution performance with a small overpotential of 178 mV at a current density of 10 mA cm?2 and maintain stable in acidic solution. This superior performance is attributed to the unique nanostructures with N, P dual-doped conductive carbon spheres with highly hollow degree as core and well-dispersed MoS2 nanosheets as shell. Therefore, this work suggests that choosing carbon matrix with large surface area as support is the key to synthesizing MoS2-based electrocatalysts with enhanced HER activity.