N-doped bimetallic NiFeP nanocubic clusters derived from Prussian blue analogues as a high-efficiency and durable water splitting electrocatalyst

The design and preparation of high-efficiency and durable non-precious metal electrocatalysts are critical to the realization of large-scale water splitting. In this work, nano cubic clusters of Ni and Fe bimetallic phos-phides (NiFeP@NC/NF) grown on NF substrates were synthesized through a simple secondary hydrothermal reaction and low-temperature phosphating. By exploring the phosphating temperature, the optimized NiFeP@NC/NF material shows excellent oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) properties in 1.0 M KOH electrolyte. It has a small initial overpotential of 286 and 242 mV and low Tafel slope of 69 and 126 mV dec(-1 )at current density of 20 mA cm(-2), which is attributed to the synergistic effect of NC@ NiFeP nanocubic clusters and NF framework, NiFeP@NC nanocubic clusters not only provide more active specific surface area but also the interlaced structure is more stable. The introduction of miscella-neous elements can accelerate the mass transfer in the reaction. The results show that NiFeP@NC/NF is an excellent dual-function electrocatalyst for water splitting and a promising candidate for electrocatalytic water splitting.