Yu Yangyang, Cui Wen, Song Lei, Liao Qingdian, Ma Kui, Zhong Shan, Yue Hairong, Liang Bin
Low-Carbon Technology and Chemical Reaction Engineering Laboratory, School of Chemical Engineering, Sichuan University, Chengdu 610065, China.
Yangtze Delta Region Institute (Huzhou) & Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Huzhou 313001, China.
ACS Appl Mater Interfaces. 2022 Feb 23;14(7):9864-9872. doi: 10.1021/acsami.1c24083. Epub 2022 Feb 9.
Superhydrophobic TiO with great application potential is mainly obtained by surface modification with low surface energy organics, which is easily degraded under sunlight irradiation, which results in the loss of superhydrophobic properties. Herein, we developed a room-temperature pulsed chemical vapor deposition (pulsed CVD) method to develop amorphous TiO-deposited TiO nanoparticles. The ultraviolet stability/ultraviolet-induced reversible wettability switch had been simultaneously realized by different and controllable deposition cycles of amorphous TiO. The superhydrophobic properties of the organic-free TiO were determined by the micrometer-nanometer-sub-nanometer multiscale structure, the multiscale pore structure, and the large Young's contact angle resulting from carboxylic acid adsorption. Also, we found that the adsorption rate and adsorption stability of oxygen and water at the surface oxygen vacancies were the key to facilitate the reversible switching between superhydrophilic and superhydrophobic states, which was well demonstrated by experimental characterization and theoretical simulation. In addition, we also found that the resistance of dense amorphous TiO films on the TiO surface to the migration of photogenerated electrons and holes was the key to maintain the stable superhydrophobic properties of superhydrophobic TiO under ultraviolet illumination. The powders were strongly ground and the coating surface was rubbed on the surface of the sandpaper, which still maintained superhydrophobic properties, providing favorable conditions for the application of superhydrophobic TiO. This work modulates the ultraviolet stability and dark/ultraviolet-induced switchable superhydrophobicity/superhydrophilicity of coated TiO by simply adjusting the number of deposition times in a pulsed CVD process for the first time, thus contributing to the development of organic-free superhydrophobic TiO.
具有巨大应用潜力的超疏水二氧化钛主要通过用低表面能有机物进行表面改性获得，但其在阳光照射下容易降解，导致超疏水性能丧失。在此，我们开发了一种室温脉冲化学气相沉积（脉冲CVD）方法来制备非晶态TiO沉积的TiO纳米颗粒。通过不同且可控的非晶态TiO沉积循环，同时实现了紫外稳定性/紫外诱导的可逆润湿性切换。无有机成分的TiO的超疏水性能由微米-纳米-亚纳米多尺度结构、多尺度孔结构以及羧酸吸附导致的大杨氏接触角决定。此外，我们发现表面氧空位处氧和水的吸附速率及吸附稳定性是促进超亲水和超疏水状态之间可逆切换的关键，实验表征和理论模拟很好地证明了这一点。另外，我们还发现TiO表面致密的非晶态TiO薄膜对光生电子和空穴迁移的阻碍是维持超疏水TiO在紫外光照下稳定超疏水性能的关键。将粉末大力研磨并在砂纸表面摩擦涂层表面后，其仍保持超疏水性能，为超疏水TiO的应用提供了有利条件。这项工作首次通过在脉冲CVD过程中简单调节沉积次数来调控涂覆TiO的紫外稳定性以及黑暗/紫外诱导的可切换超疏水性/超亲水性，从而有助于无有机成分超疏水TiO的发展。
