Nickel in nitrogen-doped graphene nanotube as efficient electrocatalyst for water splitting

Abstract

Designing an efficient bifunctional electrocatalyst for kinetically sluggish hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is a necessity for energy efficient water splitting. In this regard, we report facile synthesis of a phase pure face centered cubic (FCC) nickel electrocatalyst in nitrogen doped graphene nanotube (NGT) of diameter∼100 nm. The single step in-situ synthesis of Ni-NGT synthesized by pyrolysis is cost effective and the bifunctional catalytic activity that can compete with the state-of-the-art Pt-C and RuO2 catalyst for HER and OER, respectively. The enhanced catalytic activity can be attributed to the synergistic effect of Ni active centers, defect sites due to N-doping and the conducting NGT support.