TiO2 nano-coating with superhydrophobic surface was initially prepared through depositing TiO2 nanoparticles on the surface of porous Al2O3 microfiltration membrane by multi-layer assembly technology,then followed by a fluorination surface treatment with 1H,1H,2H,2H-perfluorodecyltriethoxysilane (PFDS).X-ray diffractometer (XRD),fourier transform infrared spectroscope (FTIR),atomic force microscope (AFM),water contact angle measurements (WCA) and scanning electron microscope (SEM) were used for membrane characterization.The crystalline structure of TiO2 nano-coating was analysed.The relationship among TiO2 nanoparticles deposition time,surface roughness and hydrophobicity was discussed.The influence of grafting time on the morphology and hydrophobicity was also researched.The result shows that with TiO2 nano-coating anatase structure is fabricated by annealing at 600℃ for 1h,With the increase of TiO2 nanoparticles deposition time,the surface becomes rougher,and the state of water droplets on it transforms from Wenzel to Cassie contact.When the TiO2 nanoparticles deposition time is 50 min and the TiO2 coating is grafted for three times,an ideal superhydrophobic surface of micro-nanometer morphology is obtained with water contact angle of 174.5°.%采用多层自组装技术在Al2O3微滤膜表面制备TiO2纳米涂层,并利用1H,1H,2H,2H-全氟辛基乙基三乙氧基硅烷(PFDS)对其表面进行氟化处理,获得超疏水改性膜.通过X射线衍射仪,傅立叶变换红外光谱仪,原子力显微镜,水接触角测试仪和扫描电子显微镜对改性膜进行表征.分析了TiO2纳米涂层的晶型结构,探讨了TiO2沉积时间与改性膜表面粗糙度和疏水性之间的关系,研究了PFDS改性次数对膜表面形貌和疏水性能的影响规律.结果表明:在600℃退火1h后,获得锐钛矿结构的TiO2纳米涂层.随TiO2沉积时间的延长,膜表面粗糙度增大,水滴在膜表面的接触由Wenzel状态转变为Cassie状态;当TiO2沉积时间为50 min,PFDS改性3次时,获得理想的微纳米二级超疏水表面形貌,水接触角达到174.5°.
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