Nonequilibrium Ti4+ Doping Significantly Enhances the Performance of Fe2O3 Photoanodes by Quenching

Abstract

AbstractHematite (α‐Fe2O3) is one of the most promising photoanodes for solar water splitting due to its narrow band gap, high photostability and low cost. Though intensive studies have been done on α‐Fe2O3 photoelectrodes in the past decades, the reported record efficiency is still much lower than the theoretical maximum value (about 16 %). High resistance is one of key challenges for high performance. In this work, we used a facile quenching method to realize nonequilibrium Ti4+ doping and decrease resistance of a Fe2O3 photoanode, which indicated much higher performance than that of a sample cooled naturally by conventional methods. To the best of our knowledge, this is the first demonstration of improving the performance of doped Fe2O3 by a quenching method. This method can serve as a reference for other doped photoelectrodes for solar water splitting.