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 band-gap photoexcitation,and to revert back to the initial conditions upon storage in dark.