A facile route for wettability regulation by modifying the submicron/nanoscale physical topography of porous films

作者:Liu, Fang; Wan, Long; Zhou, Wuyi; Li, Hui; Qiu, Zhenjie; Zhang, Shiying*; Shen, Jie*
来源:Surface and Coatings Technology, 2017, 321: 90-96.
DOI:10.1016/j.surfcoat.2017.04.047

摘要

Porous anatase TiO2 films with disparate submicron/nanoscale topographies were fabricated in this study. The wettability of the films could be regulated from super-hydrophilicity to hydrophobicity using a facile soft template route. The surface morphologies of the prepared films were investigated by FESEM and AFM, with the porous structures characterized via BET. The wetting property of the films with micro level morphology was studied by contact angle (CA) measurements. On the above basis, the macroporous surfaces (templated by triblock copolymer P123 or cetyltrimethylammonium tosylate (CTATos)) with superhydrophilicity (CA = 0) and the mesoporous surface (templated by cetyltrimethyl ammonium bromide (CTAB)) with hydrophobic characteristic (CA = 96 degrees) were detected. It is interesting to find that even though the chemical composition is hydrophilic, the hydrophobic surface could still be formed by the mesoporous topography with a possible wetting mechanism based on the Cassie model. Moreover, the morphology dominant hydrophobicity was well maintained after heating at 500 degrees C for 2 h (CA = 91 degrees), bringing the material greater potential under harsh conditions.