Ni(II)-Dimeric Complex-Derived Nitrogen-Doped Graphitized Carbon-Encapsulated Nickel Nanoparticles: Efficient Trifunctional Electrocatalyst for Oxygen Reduction Reaction, Oxygen Evolution Reaction, and Hydrogen Evolution Reaction

The successful commercialization of fuel cells and electrolyzer is limited to the cost and instability issues associated with electrocatalysts (platinum/platinum-based catalysts) used. Hence, there is critical challenge to develop stable, non-platinum-based catalysts with multifunctionality and better durability that can efficiently replace platinum. While a sufficient number of bifunctional catalysts are now known in the literature, development of trifunctional catalyst is rarely reported. Herein, we report the development of nitrogen-doped graphitized carbon-encapsulated Ni nanoparticles-based catalyst (Ni-NC700) from an easy derivable Ni(II)-dimeric complex. Microstructural studies reveal that the catalyst annealed at 700 °C has 4–5 layers of graphene sheets forming a shell surrounding the Ni nanoparticles. This catalyst exhibits outstanding trifunctional catalytic performance with onset potential of 0.86, 1.52, and −0.02 V (vs RHE) for oxygen reduction reaction, oxygen evolution reaction, and hydrogen evolution reaction, respectively. The long-term accelerated durability test and methanol tolerance test confirm better stability and durability of this catalyst than those of the benchmark Pt/C. The development of N-doped graphitized carbon shell-encapsulated Ni nanoparticles from a small binuclear Ni(II) complex will open a new horizon for the synthesis of efficient electrocatalysts with trifunctionality.