POLYCRYSTALLINE ZnO NANOWIRES OBTAINED BY PYROLIZING ZINC OXALATE-BASED NANOWIRES FROM TEMPLATE-ASSISTED SOLUTIONS
Abstract
Polycrystalline ZnO nanowires composed of nanosized grains were produced by pyrolizing one-dimensional (1D) zinc oxalate-based nanowires at 450°C. The oxalate-based nanowires were synthesized at 25°C–100°C in an aqueous solution with the aid of a hexamethyleneamide (HMA) template and catalytic ammonia. Due to its low solubility in aqueous solution, zinc oxalate was not the popular reactant for the synthesis of ZnO. With a fixed ammonia concentration and a HMA/[ZnC2O4 ⋅ H2O] molar ratio of 1, the growth of zinc oxalate-based wires was investigated by changing growth temperature and growth duration. Different growth behaviors were observed and explained based upon the decomposition rate of 
complex and the interaction between zinc oxalate molecules and surfactants. The best growth condition was at 80°C for less than 1 h. After low-temperature calcination at 450°C, zinc oxalate-based nanowires were pyrolized into polycrystalline ZnO nanowires. This synthesis provides a simple route to prepare nanoparticle-covered ZnO nanowires.
