Preparation, Characterization, And Water-droplet Kinetic Behavior Of Controllable-wetting Inorganic Nanorstructured Surface

With the development of surface science and micro-fluid motion technology, preparationof controllable-wetting surface has received considerable attention in recent years. Inorganicnanostructure materials have potential application in fabrication of controllable-wettingsurface due to their excellent thermal, chemical and mechanical stability. In this thesis, weconstructed inorganic nanostructure surfaces with controlled wettability byintensity-controlled light irradiation and selective modified methods. The kinetic behaviors ofwater droplets on these obtained surfaces were investigated too.Wetting-graded ZnO nanostructure surface （from superhydrophobic to superhydrophilic）was fabricated via intensity-graded UV light irradiation method owing to the uniquesensitivity of ZnO surface wettability to UV light. Surface structure and droplet spreadingbehavior on the sample were investigated. Cu（NO₃）₂solution droplet was asymmetric shapeon the wetting-graded surface and the gradually changed morphology of CuO crystals wereobtained after heat treatment due to the unbalanced inner tension.Wetting-patterned ZnO surface was fabricated by selective photoirradiation method.According to the behavior of droplet on this patterned surface, it found that the dropletbypassed the superhydrophobic region and then moved to the superhydrophilic region in aself-driving way though the latter has a stronger adhesion resistance than the former. Thisnovel behavior is mainly attributed to the surface tension difference on thesuperhydrophobic/superhydrophilic interface.The relative motion and fast combination of two droplets on thesuperhydrophobic-hydrophilic surface were observed, following which the oscillationphenomenon occurred because of the released interface energy during the contact process oftwo droplets. This phenomenon was used to some special chemical reactions. Thecombination of Cu（NO₃）₂and NH₃·H₂O solution droplets led to diversified morphology CuOcrystal after heat treatment. The water generated from the contact of HCl and NaOH solutiondroplets was instant gasified. The reaction of HCl and Na₂CO₃solution produced CO₂gasonly at the side of acid. This fantastic behavior will provide promising application in designand preparation of micro chemical reactor.