Preparation of an Fe-doped visible-light-response TiO2 film electrode and its photoelectrocatalytic activity

• Fe-doped TiO2 film electrodes were prepared by the sol–gel and dip-coating method.
• Their photoelectrocatalytic properties were investigated under UV light and visible light for the degradation of methyl orange and Rhodamine B.
• The Fe-doped TiO2 film electrode enhanced the photocatalytic performance under visible light.
• The decolorization reaction of Rhodamine B under visible light was a pseudo-first-order reaction.

Fe-doped TiO2 film electrodes were prepared by sol–gel and dip-coating methods, and their photoelectrocatalytic properties were investigated under both ultraviolet and visible light through degradation of methyl orange and Rhodamine B. The results showed that the Fe-doped TiO2 film electrodes mainly consisted of anatase TiO2. The Fe-doping effectively restrained the grain growth of TiO2 and the phase transformation of rutile. The modified film substantially extended the photo response from 452 nm to 604 nm and band gap decreased to 2.05 eV. The photocatalytic performance of the Fe-doped TiO2 film electrode was enhanced. The response current of 1% Fe-doped TiO2 film electrode was 30.3 μA while TiO2 film electrode had no response under visible light. The decolorization rate of RhB by 1% Fe-doped TiO2 film electrode was 22% higher than that of undoped electrode, which indicated that the extended responsive wavelength range greatly expanded the application potential of the modified electrode.