Synthesis, characterization and investigation electrocatalytic property of nickel(II) complex based on 1,2-bis(diphenylphosphino)ethane for hydrogen generation and hydrogen oxidation

The electrocatalytic processes of hydrogen evolution reaction and hydrogen oxidation reactions have emerged as global strategies to address critical environmental and energy challenges associated with fossil fuel consumption. To enhance electrocatalytic activity, we focus on the design of novel electrocatalysts based on first-row transition metal complexes. A new nickel complex [Ni(dppe)Cl 2 ] by the reaction of NiCl 2 with 1,2-bis(diphenylphosphino)ethane (dppe) were synthesized and characterized in our group. The structure of nickel complex was determined cryptographically. The electro-catalyze hydrogen evolution (HER) activity of complex Ni(dppe)Cl 2 in acetonitrile solution with acetic acid as proton and a neutral buffer (pH 7.0) medium was evaluated by controlled potential electrolysis, with a turnover frequency (TOF) of 155 and 366 (mol of H 2 /mol of cat/h), respectively. Notably, electrocatalytic activity towards hydrogen oxidation (HOR) in acetonitrile solvent using Ni(dppe)Cl 2 as a catalyst has also been studied, and the complex exhibits highly catalytic efficiency with a TOF of 0.77 s −1 . The above results indicate that the Ni complex can be act as promising electrocatalyst for HER and HOR.