Phytic acid-modified NiFe-PBA stacked by π-π force for reinforcement electrocatalytic water oxidation

Prussian blue analogues (PBAs) with unique three-dimensional (3D) open metal framework structure and easily adjustable composition have been widely used in oxygen evolution reaction (OER) under alkaline conditions. Herein, disintegrative PA-tPBA/NF (d-PA-tPBA/NF) was prepared by ion-exchange reaction, phytic acid (PA) etching and mild thermal activation using Ni(OH)2 layered nanosheets loaded on nickel foam (NF) as precursor. Due to the optimization of the NiFe-PBA@Ni(OH)2 heterostructure and π-π stacking force on the electron transfer structure, a stable high-speed charge transfer channel has been successfully constructed. Therefore, the OER overpotential required to transport 10 mA cm-2 is only 250 mV, especially with a significant Tafel slope of 47.9 mV dec-1. Furthermore, the d-PA-tPBA/NF||d-PA-tPBA/NF system achieved a current density of 10 mA cm-2 with a cell voltage of only 1.55 V. This study provides a promising strategy for exploring efficient OER electrocatalysts derived from PBA.