TiO2 nanotube photonic crystal fabricated by two-step anodization method for enhanced photoelectrochemical water splitting

TiO2 nanotube photonic crystal (TiO2 TSANTPC) is successfully fabricated via a facile two-step anodization method. The TiO2 TSANTPC exhibits a strong light absorption over a broad visible range. When it was used as a photoanode in photoelectrochemical (PEC) water splitting, the photocurrent density of the TiO2 TASNTPC was identified to be 1.1 mA/cm2 at 0.22 V vs. Ag/AgCl electrode with Faradic efficiency of 100%, which is approximately 4.8-fold enhanced over pristine TiO2 nanotube. These findings contribute to further enhancement of the PEC performance of TiO2-based photoelectrode.