Construction of a self-floating fabric based on CVD-assisted coating and its application in interfacial evaporation

Abstract

The discharge of industrial wastewater and the shortage of fresh water resources are increasingly endangering human daily life. In this experiment, bismuth oxychloride with oxygen vacancies was attached to a fabric surface using the solution deposition method, and then perfluoro-trichlorosilane was grafted on the surface to prepare a multifunctional superhydrophobic fabric. After mechanical stability testing, the fabric retained a water contact angle that consistently exceeded 150°, which could realize the selective adsorption of insoluble oil such as cyclohexane. Through a capture experiment of active species, the conclusion drawn was that holes (h⁺) and superoxide free radicals (·O₂⁻) were primary active species for the photocatalytic degradation process. After 4 cycles of photodegradation, the degradation efficiency could still reach 92.8 %, showing excellent cyclic degradation stability. An interfacial solar steam generator (ISSG) was assembled using the superhydrophobic fabric as the support layer and a polypyrrole sponge as the photothermal layer, whose evaporation efficiency under one sun reached 2.8376 kg·m⁻²·h⁻¹, with a photothermal conversion efficiency of 92.255 %. This ISSG demonstrates excellent wastewater purification capabilities. Interfacial evaporation devices show promising prospects in solar-powered wastewater purification, which further expand the use of interfacial evaporation to solve the problem of water scarcity.