Gradient Titanium Oxide Nanowire Film: a Multifunctional Solar Energy Utilization Platform for High-Salinity Organic Sewage Treatment
Pengchao Si, Qinhuan Wang, Haoran Kong, Yuting Li, Yu Wang
Abstract
The treatment of high salt organic sewage is considered to be a high energy consumption process, and it is difficult to degrade organic matter and separate salt and water simultaneously. In this study, a gradient structure titanium oxide nanowire film is developed, which can realize the thorough treatment of sewage under sunlight. Among the film, part TiO2–x has enhanced photocatalytic properties and can completely degrade 0.02 g·L–1 methylene blue in 90 min under 2 sun. Part TinO2n–1 has excellent photothermal conversion efficiency and can achieve 1.833 kg·m–2·h–1 water evaporation rate at 1 sun. Through the special structure design, salt positioning crystallization can be realized to ensure the film’s stable operation for a long time. The gradient hydrophilicity of the film ensures adequate and rapid water transfer, while the water flow can induce a significant hydrovoltaic effect. The measured VOC is positively correlated with light intensity and photothermal area and corresponds to the water evaporation rate.