Enhancing the Robustness of Superhydrophobic Coatings via the Addition of Sulfide.

Micro/nano hierarchical structures with special wettability impart a wide spectrum of unique properties to the superhydrophobic surfaces that are applicable in different potential fields. Therefore, it is necessary to develop advanced superhydrophobic materials with excellent wear-resistance properties. In this study, PDMS-based robust superhydrophobic coatings, which used MoS or WS as a solid lubricant, PDMS as a binder, and SiO as a filler, were prepared on glass substrate by the one-step air spaying method. Lamellar MoS and WS with high crystallinity had intrinsic hydrophobic properties. The MoS@SiO-PDMS (MSP) and WS@SiO-PDMS (WSP) coatings with very rough textures showed good water-repellent behavior with water contact angles of 167.8 and 166.2°, respectively. The results demonstrated that the addition of microsized MoS or WS could easily format micro/nano second-level hierarchical structures, thus realizing the superhydrophobic properties. The friction coefficient decreased gradually with the increasing in MoS or WS. A 4:1 ratio of SiO to MoS/WS could cause the samples to preserve their superhydrophobic properties even after 100 cycles on the abraser. As a result, superhydrophobic coatings with excellent wear resistance will be good candidates for water-repellent surfaces to meet practical emerging needs in industry applications.