Effect of photoelectrochemical electrolyte additives on the photoconversion efficiency of tungsten trioxide loaded titania nanotubes prepared via electrodeposition

Abstract

This study aims to investigate the effect of additives (sulfuric acid and ethanol) in sodium sulfate as photoelectrochemical (PEC) electrolyte on the photoconversion efficiency of tungsten trioxide loaded titania nanotubes (WTNT). Titania nanotubes (TNT) were first fabricated via anodization while the deposition of tungsten trioxide onto the titania nanotubes (WTNT) were successfully carried out via electrodeposition at various potentials. Assessing the PEC performance of WTNT fabricated at pH 1.5 in solely sodium sulfate was not adequate to enhance the PEC performance of WTNT compared to blank TNT. A similar result was obtained when sulfuric acid was added or when fabricating WTNT at pH 0.8. Adding ethanol into sodium sulfate electrolyte has successfully improved the PEC performance of WTNT with observable inclining photoconversion efficiency trend upon increasing electrodeposition potentials of WTNT from −0.45 V to −0.75 V.