TiO2 nanorod arrays decorated with exfoliated WS2 nanosheets for enhanced photoelectrochemical water oxidation

A novel three-dimensional (3D) photoanode consisting of TiO(2 )nanorod arrays (TiO2 NAs) coated by exfoliated WS2 nanosheets was fabricated for enhanced photoelectrochemical water oxidation. Mixed phase WS(2 )nanosheets with 1 T percentage of 55% were exfoliated by the lithium insertion, which were then coated on the top of TiO2 NAs by a drop-casting method. By optimizing the loading amount of WS2, a maximum photocurrent of similar to 1.8 mA/cm(2) could be obtained at +1.8 V vs. RHE under AM 1.5 irradiation (100 mW/cm(2)), which is 2.3 times higher compared to the pure TiO2 NAs (0.8 mA/cm(2)). The enhanced photo-activity should be attributed to the presence of the mixed phase WS2 nanosheets, which have excellent charge transport ability and can accept photogenerated holes for water oxidation. (C) 2019 Published by Elsevier Inc.