Improved electrochromic performance of a radio frequency magnetron sputtered NiO thin film with high optical switching speed

A nickel oxide (NiO) thin film with better reversibility, high optical modulation, and enhanced coloration efficiency with fast switching time was prepared using radio frequency (rf) magnetron sputtering technique. A cubic phase and spherical shaped crystal grain morphology of the NiO film have been...

Full description

Saved in:
Bibliographic Details
Published in:RSC advances 2016-01, Vol.6 (83), p.79668-7968
Main Authors: Usha, K. S, Sivakumar, R, Sanjeeviraja, C, Sathe, Vasant, Ganesan, V, Wang, T. Y
Format: Article
Language:English
Subjects:
Electrochromism
Lithium
Magnetron sputtering
Modulation
Nickel
Radio frequencies
Switching
Thin films
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:A nickel oxide (NiO) thin film with better reversibility, high optical modulation, and enhanced coloration efficiency with fast switching time was prepared using radio frequency (rf) magnetron sputtering technique. A cubic phase and spherical shaped crystal grain morphology of the NiO film have been determined from structural and surface morphological studies. A micro-Raman study showed two bands around 570 cm −1 and 1100 cm −1 corresponding to the vibrations of Ni-O. An X-ray photoelectron spectroscopic study confirmed the compositional purity and the presence of Ni 2+ and Ni 3+ ions in the film. In addition, the observed transmission threshold at about 368 nm revealed the presence of Ni vacancies or the presence of Ni 3+ ions along with Ni 2+ ions in the deposited film. The photoluminescence peak located at 368 nm in the UV region is attributed to band-edge emission, which may be due to the transition of Ni 2+ ions from the top of the 3d 8 valence band to the bottom of the 3d 8 conduction band. The electrochromic studies reveal an excellent performance with a highest coloration efficiency of 235 cm 2 C −1 , reversibility of 64%, optical modulation of 58%, coloration time of 1.2 s and bleaching time of 1.1 s. An electrochemical impedance measurement indicates fast lithium ion transfer with fast switching time, which facilitates the improved electrochromic behavior. A nickel oxide (NiO) thin film with better reversibility, high optical modulation, and enhanced coloration efficiency with fast switching time was prepared using radio frequency (rf) magnetron sputtering technique.
ISSN:2046-2069
2046-2069
DOI:10.1039/c5ra27099e