We report exploiting effective Sn incorporation to enhance the photoelectrochemical activity of WO3plate films, applied as photoanodes for photoelectrocatalytic (PEC) CO2reduction into formic acid (HCOOH). The in situ Sn-doped WO3films were prepared on a fluorine-doped tin oxide (FTO) substrates by a hydrothermal method with adding Na2SnO3as the Sn precursor. Sn dopants were confirmed with an X-ray photoelectron spectroscopy (XPS), which enlarged the growth density and crystallinity of WO3plate films. Comparing the PEC properties, Sn-doped WO3anode exhibits a photocurrent density of 1.11 ...
