OBJECTIVE The ability to deposit surfaces with switchable wettability assumes an actively pursued research area in materials science due to its implications in disparate technological fields.The reversible wetting behavior has been extensively researched for their potential applications in self-cleaning surfaces,intelligent microfluidic devices,lab-on-a-chip systems,and so on.During the numerous switchable wettability pathways,a more powerful strategy relies on the modifiable capability of some transition-metal oxides,namely TiO2,to increase their hydrophilicity under bandgap photoexcitation,and to revert back to the initial conditions upon storage in dark.To prepare a functional surface with UV-switchable wettability on cotton fabric by hybrid coating,the hybrid sol containing TiO2 and silane coupling agent,such as Triethoxyoctylsilane,Dodecyl triethoxy silane,Hexadecyltrimethoxysilane and 1H,1H,2H,2H-perfluorooctyltrimethoxysilane via sol-gel technology.The maximum contact angles of cotton fabric coated with functional TiO2 hybrid sol were more than 150°,respectively.With irradiation under UV light,the decay of the contact angle from superhydrophobicity to superhydrophilicity on the irradiated fabric treated with functionial TiO2 hybrid sol was rapid,and in the black environment,the superhydrophilic fabric was recover to superhydrophobic state.