Coupling Ti-doping and oxygen vacancies in hematite nanostructures for solar water oxidation with high efficiency

Abstract

By coupling Ti-doping and oxygen vacancies in hematite nanostructures, an efficient photoelectrode for solar water oxidation was prepared which showed a high photocurrent of 2.25 mA cm⁻² at 1.23 V vs. RHE and a remarkable maximum value of 4.56 mA cm⁻² at 1.6 V vs. RHE at a relatively low activation temperature of 550 °C. In addition, the partial oxygen pressure range suitable to produce oxygen vacancies in Ti-doped hematite could be expanded to a wide region compared to that in undoped hematite, which was critical to the photoelectrode production in practical applications. The facile way by coupling independently developed methods with the cumulative effect stands for an effective strategy for efficient solar water oxidation.