CdSe/TiO2 nanowire arrays heterojunction enhanced self-driven photoelectrocatalytic degradation of mixed organic pollutants

Abstract

Various pollutants formed by industrial production are difficult to degrade naturally and cause water pollution. This work focuses on the construction of an efficient and stable self-driven photoelectrochemical co-catalytic device for the degradation of mixed organic pollutants. CdSe nanoparticles were grown in situ on TiO₂ nanowire arrays (TNWAs) with high aspect ratios by a successive ionic layer adsorption reaction (SILAR) method, which forms a CdSe/TNWAs heterojunction and improves the PEC performance of the TNWAs. A rolling freestanding layer triboelectric nanogenerator (RFTENG) for photoelectrocatalytic degradation of mixed pollutants (methylene blue, methyl orange, and tetracycline hydrochloride) based on CdSe/TNWAs thin film photoelectrodes was assembled, which shows a greatly enhanced performance compared to the RFTENG based on TNWAs and TNWAs photocatalytic system. In addition, it shows a faster degradation rate for mixed pollutants than that of any single pollutant under the same conditions, and the total degradation efficiency of CdSe/TNWAs-PEC degradation for mixed pollutants reached 99.4 % in 4 h. The results also demonstrated that the developed device has good stability and can be applied to complex working conditions. The combination of TENG and efficient photocatalyst not only improved the photoelectrocatalytic efficiency, but also reduced energy consumption.