Bio-inspired fabrication of well-oriented ZnO nanorod arrays film and its superhydrophobicity and superhydrophilicity.

A highly oriented ZnO nanorod array film was fabricated on glass substrate by combinations of Sol-Gel and hydrothermal. The film exhibits perfect superhydrophobicity with a contact angle of 155° and a glide angle of 4° after being surface modified by fluoroalkylsilane, which is similar with wings' property and structures of large yellow spots mosquitoes. Interestingly, the ZnO nanorods film were converted from superhydrophobicity into superhydrophilicity under ultraviolet light for 2 h due to the decomposition of fluoroalkyl chain of fluoroalkylsilane and the photosensitivity of ZnO surface. The transition mechanisms of wettability are discussed on the basis of correlated theories. [ABSTRACT FROM AUTHOR]