Nickel Nanoparticles Encapsulated in Few-Layer Nitrogen-Doped Graphene Derived from Metal–Organic Frameworks as Efficient Bifunctional Electrocatalysts for Overall Water Splitting

A study is conducted to demonstrate how nickel nanoparticles encapsulated in few-layer nitrogen-doped graphene is derived from metal–organic frameworks as efficient bifunctional electrocatalysts for overall water splitting. The study demonstrates that the annealing temperature is an important parameter that can be used to tune the component and structure of these Ni@NCs materials, and thus optimizing their electrocatalytic performance. Due to the synergistic effects between the Ni nanoparticle (NP) core and the N-doped thin graphene shell, the resulting Ni@nanocrystal (NC) material exhibits highly efficient and ultrastable electrocatalytic activity toward hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) as well as overall water splitting in alkaline media.