Modulating the geometrical sites of cobalt phosphates by autologous pyrolysis for electrocatalytic water oxidation

Abstract

Herein, we report two autologous phosphates for electrocatalytic water oxidation. Although they have many similarities, the four-coordinated Co sites in Co₃(PO₄)₂ showed higher activity than the six-coordinated Co sites in Co₃(OH)₂(HPO₄)₂. This was because the four-coordination Co^II possessed a high turnover frequency and could be easily transformed into high-valent active cobalt (hydr)oxide species.