In situ electrochemical surface derivation of cobalt phosphate from a Co(CO3)0.5(OH)·0.11H2O nanoarray for efficient water oxidation in neutral aqueous solution.

In this Communication, cobalt phosphate (Co-Pi) has been successfully developed on a Co(CO3)0.5(OH)·0.11H2O nanoarray (CCH NA) on Ti mesh in neutral phosphate-buffered solution (PBS) via in situ electrochemical surface derivation. The resulting core@shell structured CCH@Co-Pi NA/Ti exhibits remarkable activity toward water oxidation with the need of an overpotential of 460 mV to achieve a geometrical catalytic current density of 10 mA cm-2 in 0.1 M PBS, with a high turnover frequency of and long-term electrochemical stability.