Suppressing the visible emission in ZnO photoluminescence

Abstract

Photoluminescence of ZnO was widely contentious field of study due to the multitude of competing sources for the different emission peaks, both UV and visible. Different growth methods and sample size also contributes to the variation in peak features obtained. This paper reports an observed suppression in visible emission of ZnO under orientation modification. ZnO bulk single crystals from hydrothermal growth method and ZnO microribbons grown by carbothermal reduction were investigated. Strong visible emission was observed for the microribbon due to its small sample size, while strong suppression of visible emission was observed for the bulk sample. Sharper band-edge emission was also observed for both samples with drastic increase for the microribbon sample.