Facile fabrication of superhydrophobic ZnO nanoparticle surfaces with erasable and rewritable wettability

In this article, ZnO nanoparticle surfaces have been fabricated successfully by a simple spray-coating method without limitations the shape and size of substrates. After being chemically modified with stearic acid, the wettability of ZnO surfaces changed from superhydrophilicity to superhydrophobicity. Furthermore, the superhydrophobicity could be erased and rewrote by the alternation of plasma or heat treatment and stearic acid coating. The process has been repeated with full reproducibility more than eight times, demonstrating that the ZnO surfaces exhibit good erasable and rewritable superhydrophobicity.