Fabrication of one-dimension ZnSe and ZnO nanostructures via anodic alumina template assisted vapor–liquid–solid growth process

Abstract

One-dimension ZnSe and ZnO nanostructures with controlled diameters from 10 to 80nm and lengths from 30nm to micrometers were grown via the vapor–liquid–solid growth process using Au nanoparticles as catalysts fabricated by anodic aluminum oxide template assisted vapor deposition. The dependence of the growth on Au nanoparticle (NP) diameters and vapor stoichiometry during growth was investigated. Statistical analysis of the dimensions of nanostructures showed that large Au NPs led to thick and long nanorods (NRs) or nanowires (NWs) within the initial growth phase, but resulted in a slow growth rate as the NRs elongate. The diameter ratio of NRs to Au NPs, or R (Dnanorod/DAu), decreases from 0.45 to 0.32 as the mean length of NRs increases from 30nm to 230nm. The composition changes as the NRs elongate, as identified by energy dispersive X-ray analysis, indicate that the stoichiometry of ZnSe NWs can be controlled from Zn-rich to Se-rich; however, for ZnO NRs and NWs, their stoichiometry maintains Zn-rich throughout the growth process. These results are significant for the controlled fabrication of one-dimension nanostructures since their optoelectronic properties are directly determined by their dimensions and composition stoichiometry.