CoFeP nanocube-arrays based on Prussian blue analogues for accelerated oxygen evolution electrocatalysis

Exploring the replacement of novel metal-based electrocatalysts based on non-precious metal is still a challenge. Transition metal-based phosphides as a kind of highly efficient oxygen reaction (OER) catalyst is considered as a judicious select for renewable energy conversion and storage. In this work, CoFeP nanocube-arrays (NCAs) composite is successfully fabricated on a 3D porous conductive substrate (nickel foam), namely as CoFeP/NF. The CoFeP/NF material exhibits exciting electrocatalytic performance with extremely low overpotentials of 253 and 290 mV at the current density of 10 and 50 mA cm −2 in 1 M KOH, respectively. Especially, remarkable durability for 100 h can be observed, which is a key parameter for practical application. CoFeP/NF||Pt/C/NF as a two-electrode system is applied into overall water splitting. A series of outstanding electrocatalytic results are obtained, including a very low voltage of 1.54 V for achieving the current density of 10 mA cm −2 with remarkable stability in 1 M KOH. These performances have far superior to commercial noble metal of IrO 2 /NF||Pt/C/NF. Therefore, this work not only provides some practical electrocatalyst materials, more importantly, it opens a feasible and universal strategy for constructing well-defined nanocube-array electrocatalysts for energy storage and conversion. • Two-step synthetic strategies are designed and applied. • Self-supporting CoFeP/NF nanocube-arrays are successfully obtained. • CoFeP/NF exhibits excellent OER electro-catalytic performance. • Excellent chemical and structural stability after 100 h can be observed. • CoFeP/NF‖CoFeP/NF cell shows high activity towards water splitting.