Nonmetal P-doped hematite photoanode with enhanced electron mobility and high water oxidation activity

Abstract

Nonmetal P-doped hematite photoanodes synthesized by a simple impregnation method during the hydrothermal preparation showed remarkable photocurrent densities of 2.3 mA cm⁻² and 2.7 mA cm⁻² at 1.23 V_RHE, for electrodes annealed at 650 °C and 750 °C, respectively. After “Co–Pi” cocatalyst modification, a photocurrent density of over 3 mA cm⁻² at 1.23 V_RHE could be achieved. The high activity can be attributed to enhanced electron mobility, as verified by DFT + U calculations, electrochemical impedance spectroscopy and structural characterizations.