A nanostructured MoO <sub>2</sub> /MoS <sub>2</sub> /MoP heterojunction electrocatalyst for the hydrogen evolution reaction
Licheng Huang, Ying Yang, Chengxin Zhang, Hui Yu, Tingting Wang, Xiangting Dong, Dan Li, Zhelin Liu
Abstract
Abstract Electrocatalytic production of hydrogen from water is considered to be a promising and sustainable strategy. In this work, the low-cost nanostructured MoO 2 /MoS 2 /MoP heterojunction is successfully synthesized by phosphorization of the pre-prepared urchin-like MoO 2 /MoS 2 nanospheres as the stable, highly efficient electrocatalysis for the hydrogen evolution reaction (HER). The MoO 2 /MoS 2 /MoP-800 (MoO 2 /MoS 2 nanospheres are phosphated at 800 °C) displays a catalytic ability for the HER with an overpotential of 135 mV to achieve 10 mA cm −2 and a Tafel slope of 67 mV dec −1 in 0.5 M H 2 SO 4 , which is superior to MoO 2 /MoS 2 nanospheres (200 °C; 24 h), MoO 2 /MoS 2 /MoP-700 (MoO 2 /MoS 2 nanospheres are phosphated at 700 °C) and MoO 2 /MoS 2 /MoP-900 (MoO 2 /MoS 2 nanospheres are phosphated at 900 °C). Meanwhile, the catalyst exhibits superior properties for HER with an overpotential of 145 mV to achieve 10 mA cm −2 and a Tafel slope of 71 mV dec −1 in 1 M KOH solution. Detailed characterizations reveal that the improved HER performances are significantly related to P-doping and the spherical nanostructure. This work not only provides a low-cost selective for electrocatalytic production of hydrogen, but also serves as a guide to optimize the composition and structure of nanocomposites.