title: Plasma-Assisted Synthesis of NiCoP for Efficient Overall Water Splitting.
abstract: Efficient water splitting requires highly active, earth-abundant, and robust catalysts. Monometallic phosphides such as Ni2P have been shown to be active toward water splitting. Our theoretical analysis has suggested that their performance can be further enhanced by substitution with extrinsic metals, though very little work has been conducted in this area. Here we present for the first time a novel PH3plasma-assisted approach to convert NiCo hydroxides into ternary NiCoP. The obtained NiCoP nanostructure supported on Ni foam shows superior catalytic activity toward the hydrogen evolution reaction (HER) with a low overpotential of 32 mV at -10 mA cm-2in alkaline media. Moreover, it is also capable of catalyzing the oxygen evolution reaction (OER) with high efficiency though the real active sites are surface oxides in situ formed during the catalysis. Specifically, a current density of 10 mA cm-2is achieved at overpotential of 280 mV. These overpotentials are among the best reported values for non-noble metal catalysts. Most importantly, when used as both the cathode and anode for overall water splitting, a current density of 10 mA cm-2is achieved at a cell voltage as low as 1.58 V, making NiCoP among the most efficient earth-abundant catalysts for water splitting. Moreover, our new synthetic approach can serve as a versatile route to synthesize various bimetallic or even more complex phosphides for various applications.
authors.affiliation: Materials Science and Engineering, King Abdullah University of Science and Technology (KAUST) , Thuwal23955-6900, Saudi Arabia.
authors.forename: Hanfeng
authors.initials: H
authors.lastname: Liang
authors.affiliation: Materials Science and Engineering, King Abdullah University of Science and Technology (KAUST) , Thuwal23955-6900, Saudi Arabia.
authors.forename: Appala N
authors.initials: AN
authors.lastname: Gandi
authors.affiliation: Materials Science and Engineering, King Abdullah University of Science and Technology (KAUST) , Thuwal23955-6900, Saudi Arabia.
authors.forename: Dalaver H
authors.initials: DH
authors.lastname: Anjum
authors.affiliation: Materials Science and Engineering, King Abdullah University of Science and Technology (KAUST) , Thuwal23955-6900, Saudi Arabia.
authors.forename: Xianbin
authors.initials: X
authors.lastname: Wang
authors.affiliation: Materials Science and Engineering, King Abdullah University of Science and Technology (KAUST) , Thuwal23955-6900, Saudi Arabia.
authors.forename: Udo
authors.initials: U
authors.lastname: Schwingenschlögl
authors.affiliation: Materials Science and Engineering, King Abdullah University of Science and Technology (KAUST) , Thuwal23955-6900, Saudi Arabia.
authors.forename: Husam N
authors.initials: HN
authors.lastname: Alshareef
keywords: DFT; HER; NiCoP; OER; electrocatalysis; plasma synthesis