Controlled growth of MoS2 nanopetals and their hydrogen evolution performance

Abstract

Edge-oriented MoS₂ nanopetals complexed with basal-oriented MoS₂ thin films have been mildly grown through a simple atmospheric pressure chemical vapor deposition (APCVD) process with the reaction of MoO₃ and S. Dense nanopetals with hexagonal structures exposed numerous chemically reactive edge sites. The roles of growth temperature, time and S/MoO₃ mass ratio have been carefully investigated to tune the morphology and density of the as-grown products. Importantly, the carbon nanotube (CNT) films were used as substrates for growing MoS₂ nanopetals. The MoS₂/CNT composites, used directly as working electrodes, showed remarkable and stable electrocatalytic activity in the hydrogen evolution reaction (HER), as manifested with a low onset overpotential of ∼100 mV and a small Tafel slope of 49.5 mV per decade. The development of the MoS₂/CNT electrode provides a promising way to fabricate other multifunctional electrodes.