Tuning Optoelectrical Properties of ZnO Nanorods with Excitonic Defects via Submerged Illumination

• DOI: 10.1021/acs.nanolett.7b00324
• Publication Date: 2017-02-03T18:04:34Z
• Authors: Melbert Jeem; Lihua Zhang; Junya Ishioka; Tamaki Shibayama; Tomio Iwasaki; Takahiko Kato; Seiichi Watanabe
• Keywords: Nanorod; Cathodoluminescence; Ultraviolet; Ultrapure water

When applied in optoelectronic devices, a ZnO semiconductor dominantly absorbs or emits ultraviolet light because of its direct electron transition through wide energy bandgap. On the contrary, crystal defects and nanostructure morphology are chief key factors for indirect, interband transitions devices visible range. By illumination ultrapure water, we demonstrate here conceptually unique approach to tune shape nanorods from tapered capped-end via apical surface control. We show that oxygen vacancy point activated by excitonic effects near tip-edge nanorod serve as an optoelectrical hotspot light-driven formation tunability properties. A double increase absorption on band edge was observed nanorod. The explanation rivals conventional electrostatics, impurity control, alkaline pH control-associated mechanisms. Thus, it highlights new perspective understanding pure neutral water.