Synthesis and characterization of Ni2P and MoS2 on MWCNT as an innovative catalytic material for hydrogen generation

Abstract

In this paper, we report the synthesis and characterization of a material composed of MoS2 nanosheets and Ni2P nanoparticles supported on MWCNT, employing two different routes. In the first one, MoS2 nanosheets were supported on MWCNT followed by a thermal decomposition reaction to grow Ni2P nanoparticles to obtain Ni2P/MoS2/MWCNT. For the second one a mixture of MoS2/MWCNT, synthesized by a solvothermal method, with Ni2P/MWCNT, synthesized by a thermal decomposition reaction method, was prepared to obtain (Ni2P,MoS2)/MWCNT. SEM and TEM images of Ni2P/MoS2/MWCNT and (Ni2P, MoS2)/MWCNT, show their morphology. For Ni2P/MoS2/MWCNT, Ni2P grown on the surface of MoS2/MWCNT, and for (Ni2P, MoS2)/MWCNT, the mixture was clearly identified. X-ray diffraction pattern confirms the formation of Ni2P on the MoS2/MWCNT in Ni2P/MoS2/MWCNT and (Ni2P, MoS2)/MWCNT composed of Ni2P, MoS2, each one supported on MWCNT. It was observed that compared to Ni2P/MWCNT, MoS2/MWCNT, and Ni2P/MoS2/MWCNT, the mixture of (Ni2P, MoS2)/MWCNT exhibits the best electrocatalytic activity for HER with a low onset overpotential of 50.42 mV (vs. RHE) and a small Tafel slope of 47 mV/dec. Also, the compound showed good stability for 50 h. The impedance spectroscopic study also confirmed that charge transfer resistance of (Ni2P, MoS2)/MWCNT is lower (19.7 Ω) than Ni2P/MoS2/MWCNT (86.5 Ω).