Improved solar water splitting performance of BiVO4 photoanode by the synergistic effect of Zr-Mo co-doping and FeOOH Co-catalyst layer

Abstract

In this work, Zr-Mo co-doping was successfully employed on electrochemically deposited BiVO4 photoanodes, and tested for photoelectrochemical (PEC) water oxidation. Zr doping induced the formation of relatively smaller morphological features resulting in improved light absorption and PEC activity. Mo doping resulted in structural damage that enhanced the charge carrier separation and increased free carrier density. The synergetic effect of both dopants resulted in ∼5-fold enhancement of the PEC performance. When a FeOOH layer is hydrothermally grown on the Zr-Mo co-doped BiVO4 electrode, the photocurrent density was enhanced by ∼13-fold achieving 3.34 mA/cm2 at 1.23 VRHE. In addition, the onset potential was remarkably reduced from ∼0.45 V to <0.1 V.