Investigation on Ce-doped TiO2-coated BDD composite electrode with high photoelectrocatalytic activity under visible light irradiation

Ce-doped titania nanoparticles, which prepared at low temperature, were deposited onto a boron-doped diamond (BDD) film via a dip-coating method. The sample was characterized by X-ray diffraction analysis, scanning electron microscopy and UV–vis diffusion reflection spectrum. The photoelectrochemical measurement of the as-prepared composite electrode showed a clear improvement in the photocurrent under visible light irradiation. Furthermore, the composite electrode was applied in the degradation of a typical azo dye X-3B via photocatalysis, electro-oxidation and photoelectrocatalysis processes. Results showed that the degradation rate in the photoelectrocatalysis process was larger than the sum of photocatalysis and electro-oxidation processes, and the synergetic factor reached 1.5.

► Ce-doped TiO2-coated BDD composite electrode was designed for the first time.
► The composite electrode shows high activity for dye degradation.
► The composite electrode can be excited by visible light.
► The recombination rate of photo-induced charge pairs can be decreased.
► It exhibits a synergetic factor of 1.5 for dye degradation.