Core -shell magnetic nanoparticles for substrate -Independent super- amphiphobic surfaces and mechanochemically robust liquid marbles

Super-amphiphobic surfaces are limited either by the specific micro-morphologies which are difficult to fabricate on particular substrates, or by the liquid-repellent ability which is confined to liquids with surface tension (gamma) higher than about 24 mN m(-1). To resolve this problem, a facile method was developed by introducing low surface energy building blocks to a surface for the purpose of realizing the combination between low surface energy and hierarchical structures with reentrant-like geometry. Magnetic nanoparticles with typical core-shell structure were synthesized through one-pot graft polymerization with amino silane and fluorosilane surfactant. By spraying or dip-coating method, a super-amphiphobic surface can be prepared on various substrates which can repel n-heptane (gamma = 19.68 mN m(-1)) with sliding angle no more than 5 degrees. The micro-morphology and chemical composition were optimized to achieve desired surface wettability. Thanks to the high super-amphiphobicity of the nanoparticles, the liquid marbles (LMs) with organic solvents have been obtained by using the core shell nanoparticles as the building blocks. The formed LMs can act as microdroplet carriers with the ability of repeatable tip opening-closing and magnetic-driven directed movements. Chromogenic reaction was realized in the LMs, which demonstrated the LMs can act as a desirable miniature reactor. Details of impact-resistance, motion stability, anti-corrosion properties and thermal stability for LMs have been investigated, which are of interest in applications of microfluidic system and microreactors.