電析法による微細花状構造を有する酸化亜鉛膜の形成と形態制御

Abstract

A characteristic micro-flower structure of zinc oxide (ZnO) was obtained using cathodic electrodeposition from a zinc chloride solution containing an organic dye (Eosin Y) and a nonionic surfactant (TritonX-100). Cyclic or linear-sweep voltammetry using a rotating-disc electrode was employed to analyze the micro-flower structure formation process. The dye forms a complex with zinc cation (Zn2+) to control the deposition as oxide, which is accompanied by pH change near the cathode. The surfactant concentration and the disc electrode rotation rate are key factors determining the deposit morphology. In the solution containing optimum surfactant concentration, the rate of oxygen reduction reaction is increased to produce ZnO. The size and the shape of the complex of Zn2+-dye-surfactant influence the micro-flower structure of the deposit. This report presents a schematic model for the micro-flower formation mechanism. Using the model, the ZnO micro-flower size was controlled experimentally according to the surfactant molecular weight.