Study of a TiO2/Ti4O7-coated plastic optic fiber photo-anode for advanced oxidation processes

Using the dip-coating technique, a photo-anode based on a plastic optical fiber (POF) was coated with a mixture of titanium oxide nanoparticles (TiO2:Ti4O7). The semiconductor-coated material was prepared so that UV radiation fed into the fiber would escape along its path, photo-exciting the electrically polarized semiconductor film and producing oxidant species capable of degrading pollutant chemicals in aqueous solution. The photoelectrode was developed to evaluate the potential degradation of organic pollutants in aqueous solutions, and for this purpose, methyl red was used to assess the photo-anode performance under photocatalysis, electrocatalysis, and photo-electrocatalysis processes. The results revealed that, as expected from the specific properties of TiO2 and Ti4O7, the TiO2:Ti4O7-coated POF substrates showed a synergistic effect when UV light and electrical polarization are applied. The main purpose of using POFs instead of conventional SiO2 fibers is that the former implies substantially lower cost and mechanical flexibility, which will result in the future novel photo-electrochemical arrangements for water treatment.