Few-layer tiny nanoflakes of molybdenum sulfide loaded on porous carbon as an efficient electrocatalyst for hydrogen generation

A promising non-precious metal electrocatalyst having efficient activity in hydrogen evolution reaction (HER) is a crucial for environmentally benign energy production. Molybdenum sulfide (MoS 2 ) is expected to be a promising alternative to noble-metal-based electrocatalysts, but its catalytic performance is inherently limited by sparse catalytic edge sites and poor electrical conductivity . Herein, we propose a convenient and scalable approach to construct few-layer tiny MoS 2 nanoflakes anchored on porous carbon (MoS 2 @C), consisting of ultrasonic spray pyrolysis (USP) followed by sulfurization. The MoS 2 @C exhibits superior HER performance with a low overpotential of 133 mV at a current density of 10 mA cm −2 , and a small Tafel slope of 66 mV dec −1 . The activity is ascribed to abundant defects in few-layer tiny MoS 2 nanoflakes, as well as enhanced electron transport from porous carbon support to active sites.