標題: Tunable Spectrum Selectivity for Multiphoton Absorption with Enhanced Visible Light Trapping in ZnO Nanorods
作者: Tan, Kok Hong
Lim, Fang Sheng
Toh, Alfred Zhen Yang
Zheng, Xia-Xi
Dee, Chang Fu
Majlis, Burhanuddin Yeop
Chai, Siang-Piao
Chang, Wei Sea
材料科學與工程學系
Department of Materials Science and Engineering
關鍵字: light absorption ability;light trapping;multiphoton absorption;photoelectrochemical (PEC);zinc oxide nanorods
公開日期: 17-May-2018
摘要: Observation of visible light trapping in zinc oxide (ZnO) nanorods (NRs) correlated to the optical and photoelectrochemical properties is reported. In this study, ZnO NR diameter and c-axis length respond primarily at two different regions, UV and visible light, respectively. ZnO NR diameter exhibits UV absorption where large ZnO NR diameter area increases light absorption ability leading to high efficient electron-hole pair separation. On the other hand, ZnO NR c-axis length has a dominant effect in visible light resulting from a multiphoton absorption mechanism due to light reflection and trapping behavior in the free space between adjacent ZnO NRs. Furthermore, oxygen vacancies and defects in ZnO NRs are associated with the broad visible emission band of different energy levels also highlighting the possibility of the multiphoton absorption mechanism. It is demonstrated that the minimum average of ZnO NR c-axis length must satisfy the linear regression model of Z(p,min) = 6.31d to initiate the multiphoton absorption mechanism under visible light. This work indicates the broadening of absorption spectrum from UV to visible light region by incorporating a controllable diameter and c-axis length on vertically aligned ZnO NRs, which is important in optimizing the design and functionality of electronic devices based on light absorption mechanism.
URI: http://dx.doi.org/10.1002/smll.201704053
http://hdl.handle.net/11536/145078
ISSN: 1613-6810
DOI: 10.1002/smll.201704053
期刊: SMALL
Volume: 14
Appears in Collections:Articles