Novel Process to Conductive Silver Nanowires Film via Simple Evaporative Crystallization of Silver Acetate/Polymer Solution on Substrates

摘要

Evaporative crystallization is a simple and widely used technique to obtain crystals. However, this is not well matching with preparation of nano scale crystals. In this study, a new method is established of self-controlled evaporative crystallization of silver acetate in aqueous solution into crystalline silver acetate nanowire, which can conduct to the fabrication of conductive AgNWs films without presynthesis of metallic silver and printing equipment. In this method, the most important concept is to self-control the anisotropic crystallization of metal ion by designed amphiphilic polyethyleneimine-block-polyphenyloxazoline (PEI-b-PPOZ) copolymers. Only casting an aqueous solution of silver acetate (AgOAc) containing PEI-b-PPOZ copolymers on substrate made silver acetate to grow spontaneously up towards networked crystalline nanowires (with high aspect ratio over 3000) film. This is completely directed by PEI-b-PPOZ block copolymers with water evaporation at ambient conditions. Heating of the crystalline AgOAc nanowires film at 200 degrees C yields metallic silver nanowires films which exhibit low sheet resistance of 20 omega per sq indicating that the crystalline AgOAc nanowires can self-template the thermal decomposition of AgOAc to give metallic nanowires.