Cerium-Doped Iron Oxide Nanorod Arrays for Photoelectrochemical Water Splitting.

In this work, a simple one-step hydrothermal method was employed to prepare the Ce-doped Fe 2 O 3 ordered nanorod arrays (CFT). The Ce doping successfully narrowed the band gap of Fe 2 O 3 , which improved the visible light absorption performance. In addition, with the help of Ce doping, the recombination of electron/hole pairs was significantly inhibited. The external voltage will make the performance of the Ce-doped sample better. Therefore, the Ce-doped Fe 2 O 3 has reached superior photoelectrochemical (PEC) performance with a high photocurrent density of 1.47 mA/cm 2 at 1.6 V vs. RHE (Reversible Hydrogen Electrode), which is 7.3 times higher than that of pristine Fe 2 O 3 nanorod arrays (FT). The Hydrogen (H 2 ) production from PEC water splitting of Fe 2 O 3 was highly improved by Ce doping to achieve an evolution rate of 21 μmol/cm 2 /h.