Fe(III) doped and grafted PbTiO3 film photocathode with enhanced photoactivity for hydrogen production

The photoelectrochemical activity of the PbTiO3 film photocathode deposited on indium tin oxide-coated quartz substrate was significantly improved through modifying the film surface by both the Fe(III) doping and grafting. Doping the PbTiO3 with Fe(III) ions narrows its band gap thus increases the visible light utilization, while the surface-grafted Fe(III) ions on the doped PbTiO3 surface are helpful to improve the charge transfer on the photocathode/electrolyte interface. Consequently, the photocurrent was increased from 38 μA/cm2 to 220 μA/cm2 under the irradiation of 100 mW/cm2 Xe lamp by using 0.1M Na2SO4 as an electrolyte and zero-potential versus saturated calomel as a reference electrode. The corresponding increase in open circuit voltage was 0.95–1.11 V.