Bai Xue, Yang Qing, Li Haoyu, Huo Jinglan, Liang Jie, Hou Xun, Chen Feng
State Key Laboratory for Manufacturing System Engineering and Shaanxi Key Laboratory of Photonics Technology for Information, School of Electronic Science and Engineering, Xi'an Jiaotong University, Xi'an 710049, PR China.
School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an 710049, PR China.
Langmuir. 2022 Apr 19;38(15):4645-4656. doi: 10.1021/acs.langmuir.2c00167. Epub 2022 Apr 4.
Superhydrophobic surfaces have aroused increasing attentions in the fields of self-cleaning, anti-fouling, heat transfer, etc. However, one of the major problems of the artificial superhydrophobic surface in practical applications is the poor durability. Inspired by the self-healing property of nature organism, we developed a sunlight-driven recoverable superhydrophobic surface by femtosecond laser constructing micropillar array on the surface of the photo-responsive shape-memory polymer (SMP). The photo-responsive SMP composite was prepared by adding reduced graphene oxide (RGO) into thermal-responsive SMP matrix. Due to the excellent sunlight-to-heat transformation property of RGO, the temperature of the as-fabricated RGO-SMP composite could be rapidly increased above the shape transformation temperature of the RGO-SMP under one sunlight irradiation. Once the micropillar array of the RGO-SMP composite was deformed by pressing or stretching treatments, the surface would lose superhydrophobicity. Upon sunlight irradiation, the surface morphology and the wettability of the RGO-SMP micropillars could completely recover to the original states. Meanwhile, this reversible morphology and wettability transformation process could be repeated multiple times. We envision that such a sunlight-recoverable superhydrophobic surface will have great applications in the future.
超疏水表面在自清洁、防污、热传递等领域引起了越来越多的关注。然而，人工超疏水表面在实际应用中的一个主要问题是耐久性差。受自然生物体自愈特性的启发，我们通过飞秒激光在光响应形状记忆聚合物（SMP）表面构建微柱阵列，开发了一种阳光驱动的可恢复超疏水表面。通过将还原氧化石墨烯（RGO）添加到热响应SMP基体中制备了光响应SMP复合材料。由于RGO具有优异的阳光到热的转化性能，在一次阳光照射下，制备的RGO-SMP复合材料的温度可以迅速升高到RGO-SMP的形状转变温度以上。一旦RGO-SMP复合材料的微柱阵列通过挤压或拉伸处理而变形，表面将失去超疏水性。在阳光照射下，RGO-SMP微柱的表面形态和润湿性可以完全恢复到原始状态。同时，这种可逆的形态和润湿性转变过程可以重复多次。我们设想，这样一种阳光可恢复的超疏水表面在未来将有很大的应用前景。
