Novel synthesis method of ZnO nanorods by ion complex transformed PVA-assisted nucleation

A novel process for preparing ZnO nanorods on a Si (1 1 1) or (1 0 0) substrate by ion complex transformed PVA-assisted nucleation is presented in this paper. This process involves two steps: highly regular Zn(OH)2 on a Si substrate were first synthesized via OH groups on the PVA chains complexed with some of zinc ions in a mixed aqueous solution containing Zn(OOCCH3)2 or ZnCl2 and then the synthesized Zn(OH)2 decomposed into ZnO nanoseeds at temperature of about 125 °C which grew gradually up into ZnO nanorods on the substrate in zinc and oxygen vapors at temperature of 400–600 °C. The results of XRD, FE-SEM indicate that the ZnO nanorods are rather evenly distributed on the substrate and possess a single crystal hexagonal wurtzite structure with preferred c-axis orientation. The room temperature PL spectra of the ZnO nanorods exhibit a strong UV emission of about 386 nm and a weak green emission of around 506 nm. The structural and optical characteristics indicate that the ZnO nanorods by this processing are of high crystal quality.