Super-robust self-healing superhydrophobic coating with triboelectrification induced liquid self-repellency

Superhydrophobic surfaces integrated with liquid self-repelling property have great application potential, nevertheless, it remains a major challenge for simultaneously achieving super-robust feature and extreme superhydrophobicity. In this work, a super-robust self-healing superhydrophobic coating containing cyclic olefin copolymer (COC), fluorinated alkyl silane (FAS) and polytetrafluoroethylene (PTFE) nanoparticles, is prepared by a convenient one-step wet-chemical coating method. The treated fabric has water contact angle of 168˚and sliding angle of 3˚. The coating demonstrates excellent endurance to various severe damages, e.g., repeated washing, abrasion, boiling water, strong UV irradiation, extremely high and low temperature. It also shows self-healing capability from physical/chemcial damages. Benefitting from the triboelectric negative features of COC and PTFE, this coating shows triboelectrification induced water self-repellence after rubbing with a polyamide (Nylon) fabric, water droplets can jump/move off the tribo-charged area. Moreover, this self-repelling feature works with many different aqueous liquids, such as NaCl, strong acid and alkali. Such a robust superhydrophobic coating can be applied onto many other substrates, such as cotton fabric, glass and cotton, and the treated substrates also exhibited liquid self-repellent properties after rubbing with a Nylon fabric. This triboelectrification enhanced superhydrophobic coating might shed light on developing energy-efficient liquid self-removing surfaces for various applications.