Rational Design of NiSe/ReSe₂Nanocomposite For Efficient Electrochemical Hydrogen Evolution Reaction

Abstract

The hydrogen evolution reaction (HER) in renewable energy systems has long been a fascinating process, but designing highly efficient and ultrastable electrocatalysts is challenging. Transition metal-based heterostructure nanohybrids are currently drawing more interest in the field of electrolysis because nanohybids can optimize kinetic processes while simultaneously lowering charge transfer resistance and increasing the electrochemically active electrode's surface area at the reaction interface. Here, we propose a concept for a two-step colloidal hot injection electrocatalyst based on NiSe/ReSe2 nanocomposites that is extremely effective for hydrogen evolution under acidic conditions. The as-obtained nanocomposite material worked efficiently, attaining a current density of 10 mA/cm2 at a substantially lower over-potential of 120 mV versus RHE as compared to each of the individual components i.e NiSe nanoparticles and ReSe2 nanosheets. As single component catalysts, ReSe2 nanosheets and NiSe nanoparticles, however, achieved current densities of 10 mA/cm2 at higher overpotentials of 172 mV and 221 mV, respectively. Even more intriguingly, the NiS/ReSe2 nanocomposite is believed to give a faster kinetic process for HER, as evidenced by a Tafel slope of 115 mV/dec, which certainly is lower than that of the 179 mV/dec and 190 mV/dec for pure NiSe and ReSe2, respectively.