In-situ transformation into MoP/MoS2 heterogeneous structure with rich S-vacancy enhanced hydrogen evolution reaction

The surface modification strategy has broken through the restriction of hydrogen evolution activity caused by low conductivity inert surfaces of MoS 2 during hydrogen evolution reaction . In this work, a new strategy for regulating the interface structure between MoS 2 and MoP using sulfur vacancy is proposed, which is derived from the synthesis of molybdenum disulfide nanotubes with rich S-vacancy (Sv-MoS 2 ) by reduction. Subsequently, Sv-MoS 2 was phosphated by introducing a P source, and the obtained (MoP/Sv-MoS 2 -8) composite. The introduction of P atoms provides more active sites for hydrogen adsorption and desorption by replacing S atoms to form (Mo-P) covalent bonds , further increase the number of S vacancies to activate the inert interface. The synthesized MoP/Sv-MoS 2 -8 has excellent catalytic activity and good cyclic stability, showing a lower Tafel slope of 60 mV·dec −1 at a current density of 10 mA·cm −2 , and no potential attenuation after the cyclic stability test for 24 h. The excellent HER performance is mainly due to the synergistic effect of P atom doping and S vacancy, which greatly reduces the energy barrier of the Volmer step and the adsorption/desorption of the H* intermediate step.