3D re-entrant nanograss on microcones for durable superamphiphobic surfaces via laser-chemical hybrid method

The potential applications of superamphiphobic surfaces are widespread and attractive. The design of re-entrant structures is crucial to superamphiphobic surfaces. However, both the existing two strategies to design re-entrant structures face problems. Here a creative strategy to design 3D re-entrant nanostructures on ordered micro-structures is proposed. A novel "Top-down" and "Bottom-up" hybrid method consisting of ultrafast laser ablation and chemical bath processing is used to fabricate hierarchical surfaces with 3D re-entrant CuO nanograss on Cu microcones. Thanks to the low surface energy from modification with perfluorodecyltrimethoxysilane and plenty of re-entrant geometries provided by the 3D distributed nanograss structures, the hierarchical surfaces show outstanding superamphiphobicity with water and low surface tension liquid like dodecane. The influence of the nanograss types and the microcone distribution on the superamphiphobicity are systematically studied. Besides, the microcones/nanograss hierarchical superamphiphobic surfaces show excellent long-term durability, high temperature durability and comprehensive mechanical durability, are promising for practically applications.