Optical properties from photoelectron energy-loss spectroscopy of low-temperature aqueous chemically synthesized ZnO nanorods grown on Si

Denis David,Clas Persson,Antonio Ferreira Da Silva,Hatim Alnoor,Pascal Bargiela,Victor Mancir Da Silva Santana,Magnus Willander,Omer Nur,Gustavo Baldissera

doi:10.1088/1361-6641/ab0bc4

Abstract

The optical properties of zinc oxide (ZnO) nanorods (NRs) synthesized by the low-temperature aqueous chemical method on top of silicon (Si) substrate have been investigated by means of photoelectron energy loss spectroscopy (PEELS). The ZnO NRs were obtained by the low temperature aqueous chemical synthesis on top of Si substrate. The measured valence band, the dynamical dielectric functions and optical absorption of the material show a reasonable agreement when the trending and shape of the theoretical calculations are considered. A first-principle calculation based on density functional theory (DFT) was performed using the partially self-consistent GW approximation (scGW0) and compared to the experimental results. The application of these two techniques brings a new analysis of the electronic properties of this material. The experimental results regarding the density of states (DOS) obtained for the valence band using x-ray photoelectron spectroscopy (XPS) was found to be consistent with the theoretical calculated value. Due to this consistency, the same wavefunctions was then employed to calculate the dielectric function of the ZnO NRs. The experimentally extracted dielectric function was also consistent with the calculated values.

Highlights

The optical properties of zinc oxide (ZnO) nanorods (NRs) synthesized by the low-temperature aqueous chemical method on top of silicon (Si) substrate have been investigated by means of photoelectron energy loss spectroscopy (PEELS)
We investigated the optical properties of ZnO nanorods obtained by a low temperature aqueous chemical process employing experimental and theoretical methods have presented an optical characterization of the ZnO NRs
We obtained a calculated density of states (DOS) that matches with the experimental measurement of the valence band by x-ray photoelectron spectroscopy (XPS)

Summary

Introduction

ZnO nanorods (NRs) possess an excellent optical properties such as direct wide bandgap (3.7 meV, at room temperature) together with relatively high exciton binding energy (60 m eV) and the presence of the light emitting intrinsic point defects [1,2,3,4]. All these optical properties makes ZnO NRs to have a potential in the development of many functional devices such as ultraviolet (UV) photodetectors [6,7,8], light-emitting diodes (LEDs). To investigate these optical properties in more details and to fulfill the advantage of

Methods

Results

Conclusion