Rose-like Nanocomposite of Fe-Ni Phosphides/Iron Oxide as Efficient Catalyst for Oxygen Evolution Reaction

Chem Asian J. 2019 Aug 1;14(15):2744-2750. doi: 10.1002/asia.201900489. Epub 2019 Jul 3.

Abstract

In order to accelerate the reaction rate of water splitting, it is of immense importance to develop low-cost, stable and efficient catalysts. In this study, the facile synthesis of a novel rose-like nanocomposite catalyst (Ni2 P/Fe2 P/Fe3 O4 ) is reported. The synthesis process includes a solvothermal step and a phosphatization step to combine iron oxides and iron-nickel phosphides. Ni2 P/Fe2 P/Fe3 O4 performs well in catalyzing oxygen evolution reaction, with a very low overpotential of 365 mV to reach 10 mA cm-2 current density. The Tafel slope is as low as 59 mV dec-1 . Ni2 P/Fe2 P/Fe3 O4 has a large double-layer capacitance that contributes to a high electrochemically active area. Moreover, this catalyst is very stable for long-term use. Therefore, the Ni2 P/Fe2 P/Fe3 O4 catalyst has a high potential for use in oxygen evolution reactions.

Keywords: bimetallic catalysts; energy conversion; iron-nickel phosphide; oxygen evolution reaction; water splitting.