Solid–liquid interfacial growth of copper sulphide nano-crystals on surface modified polyimide surfaces

Abstract

Copper sulphide nano-crystals were grown on polyimide films via an interfacial reaction of copper ions-doped precursors in sodium sulphide solution during which double diffusion and interfacial precipitation reaction occurred between the interfaces of the polyimide films and the aqueous surroundings. The newly formed copper sulphide was amorphous and distributed uniformly on the surfaces of polyimide films, and subsequent thermal treatment in vacuum transformed the amorphous copper sulphide to hexagonal crystals ones. The adhesion properties between the copper sulphide and PI substrates are unique and the mechanical properties of nanocomposite films are similar to their parent films because its inside is intact during the whole processes. This simple strategy might be extended to fabricate other quantum dots on polyimide films, which might show multi-functions based on the various species of the metal sulphides.