Na+-induced in situ reconstitution of metal phosphate enabling efficient electrochemical water oxidation in neutral and alkaline media

Exploring highly activity and stable electrocatalysts for oxygen evolution reaction (OER) is of vital importance for sustainable energy conversion processes. Herein, a facile strategy is developed to synthesize Ni-doped CoOOH nanosheets with poor crystallinity and 3D mesh structure, which is in situ derived from the Na+-induced spontaneous reconstitution of polymetallic phosphate precursors during OER process. The resulted Ni-CoOOH/NF with a large number of active sites exhibits a highly efficient OER catalytic activity outperforming the commercial RuO2 catalysts, indicated by low overpotentials of only 265 and 410 mV at a current density of 10 mA cm−2 in alkaline and neutral media, respectively. This Na+-induced in situ conversion strategy opens up a new way for the design and synthesis of electrocatalysis towards various energy systems.