Phosphorus and Aluminum Codoped Porous NiO Nanosheets\nas Highly Efficient Electrocatalysts for Overall Water Splitting

Abstract

We present a facile way to fabricate\nphosphorus and aluminum codoped\nnickel oxide-based nanosheets by using layered double hydroxide (AlNi-LDH)\nas precursors, which showed an overall water-splitting performance\nin alkaline solution. The codoping of phosphorus and aluminum into\nnickel oxide nanosheets leads to an optimum balance among surface\nchemical state, electrochemically active surface area, and density\nof active sites. As a result, it can afford a current density of 100\nmA cm^–2 at the overpotential of 310 mV for oxygen\nevolution reaction (OER) and a current density of 10 mA cm^–2 at the overpotential of 138 mV for hydrogen evolution reaction (HER)\nin 1 M KOH. When it was used as a bifunctional catalyst in a two-electrode\nwater-splitting device, a potential of 1.56 V was achieved at the\ncurrent density of 10 mA cm^–2.