Facile synthesis of nickel diselenide particles for alkaline oxygen evolution by atmospheric pressure hydrothermal method

Nickel-based selenides have attracted widespread attention as promising electrocatalysts for water splitting. This work proposes a novel and facile method to fabricate an efficient electrocatalyst based on morphological controlled nickel diselenide nanoparticles using L-cysteine (NiSe 2 -L) via atmospheric pressure hydrothermal. The NiSe 2 -L was prepared inside a round-bottom flask under stirring conditions in an oil bath at 100 ℃ for 4 h. This method no longer required posttreatment, just used L-cysteine for morphological control, and the reaction time was shortened to only 4 h. As expected, the NiSe 2 -L electrode exhibited good catalytic performance towards oxygen evolution reaction (OER) with an overpotential of 398 mV at the current density of 100 mA cm −2 and maintained a Faraday efficiency of up to 99% in 1 M KOH. Moreover, this electrode showed long-term stability with small overpotential increases (~ 16 mV) at 100 mA cm −2 after 5000 cycles of CV scans. Therefore, this work provided a facile synthesis method of nickel-based selenides with potential use value for OER in alkaline solutions.