Synthesis And Characterization Of Superwettability Materials With Photocatalytic Properties

Wettability and photocatalysis are two extremely important interfacial properties.Recently,inspired by superwetting biologies in nature,materials with different bionic wettability have been extensive reported,such as superhydrophilic,superhydrophobic,patterned wettability,superoleophobic and so on.In the meantime,photocatalysis is a technology that can convert light energy into chemical energy,which has also attracted widespread attention in recent years.At present,the research on the combination of two interface properties,superwetting and photocatalysis,is in the preliminary stage of exploration.Based on this,this thesis mainly expounds the application of two photocatalytic materials with different wettability in environmental chemistry.The main research contents are as follows:（1）Inspired by cactus thorn and desert beetle,a patterned superwetting material with photocatalytic function was prepared,which can capture and purify water from air.Firstiy,six superhydrophilic triangular patterns prepared with P25 Ti O₂ nanoparticles（NPS）were constructed on the candle soot@polydimethylsiloxane（CS@PDMS）superhydrophobic surface.The superhydrophilic region with special shape could not only effectively capture water from the foggy environment,but also the Laplace pressure gradient generated by the triangular shape could accelerate the transfer of water droplets in the superhydrophilic region,which was conducive to fog harvesting.The water collection rate（WCR）of pattern superwetting surface was 14.9±0.2 mg min^-1 cm^-2,which was respectively 5.3 times and 2.5times higher than uniformed superhydrophilic and superhydrophobic surfaces.Due to the existence of photocatalytic P25 NPs in the superhydrophilic region,the pollutants in the harvested water could be degraded under UV light(365 nm,5.0±0.6 m W cm^-2).9 kinds of pesticides were used to simulate wastewater,Ten zebrafish were put into the purified water and observed survived more than 480 hours.Under the same conditions,the same number of fish died within 7 hours in untreated wastewater.This study provides a new idea for the combination of patterned wetting and photocatalysis,aiming to break a new sight for the acquisition and utilization of fresh water.（2）An inorganic-organic superhydrophobic photocatalytic coating was prepared by grafting PDMS with stable chemical properties and excellent mechanical properties onto P25NPs under UV light(365 nm,5.0±0.6 m W cm^-2).The prepared coating was used for fabric modification,which endowd the fabric with superhydrophobic and photocatalytic properties.The modified fabric could be used for the separation of oil-water mixture.The separation efficiency was higher than 99%,showing excellent separation performance.In addition,the fabric also had photocatalytic properties,could degrade organic pollutants in water,realized the self-cleaning function.After 100 times of sandpaper friction,100 hours of high temperature（150℃）,100 hours of low temperature（-20℃）and 100 hours of UV irradiation,the modified fabric still showed stable superhydrophobic properties.The preparation of superhydrophobic photocatalytic fabrics has certain practical value,low instrument cost and simple experimental process,which is conducive to practical production.