Fabrication of heterostructured β-Bi_2O_3-TiO_2 nanotube array composite film for photoelectrochemical cathodic protection applications

摘要

An ordered TiO2 nanotube array (NTA) film was first fabricated on a Ti substrate by anodization, beta-Bi2O3 nanoparticles were then electrodeposited on the film for obtaining a heterostructured beta-Bi2O3-TiO2 NTA composite film with enhanced photocathodic protection performances. Compared to the bare TiO2 NTA film, the composite film showed a wider light absorption region and higher charge carrier separation efficiency. Under white light illumination, the composite film as a photoanode made the potential of 403 stainless steel in a 0.5 M NaCl solution decrease by 450 mV relative to its corrosion potential, showing an effective photoelectrochemical cathodic protection effect.