Controlled growth of ZnO nanostructures prepared by catalytic-immersion method

This paper presents an efficient method to prepare ZnO nanostructure via immersion of Si substrate with catalyst assistance (gold) (Au/Si) in the mixture of zinc nitrate hexahydrate (Zn(NO₃)₂.6H₂O) and urea (CH₄N₂O). The effect of precursor concentration ranging from 0.01 to 0.6 (molar ratio 1:1) was evaluated in this study. Solution-immersion method was adopted with the intention to develop a large area deposition at low-temperature. As concentration increase, the morphologies changed from rod (diameter ~208 nm and length ~ 920) to accumulated nano-sheets that consist of many pores. The structural, morphology and photoluminescence effect of changing the precursor concentration on the synthesization of ZnO films were investigated by X-ray diffractometer (XRD), field emission scanning electron microscope (FESEM) and room temperature photoluminescence (PL) measurement, respectively. A unique development of size and growth orientation is seemingly affected by the change of the precursor concentration.