Investigation of electrodeposited NiO films as electrochromic material for counter electrodes in “Smart Windows”
- Central Laboratory of Solar Energy and New Energy Sources, Bulgarian Academy of Sciences, 72 Blvd Tzarigradsko Chaussee, Sofia, Bulgaria
- Received 21 November 2013
- Accepted 28 November 2013
- Available online 6 December 2013
Highlights
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We obtain electrochemically derived NiO to serve as a counter electrode in electrochromic devices such as “Smart Windows".
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We found that the deposited NiO films are amorphous.
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NiO films have good initial transparency of 50–60%, which highly improves after annealing at elevated temperatures, and reaches almost 90%.
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Electrodeposited NiO films are non-stoichiometric.
Abstract
Nickel oxide (NiO) thin films were prepared by electrodeposition onto ITO coated glass substrates in one step deposition at 20 and 40 min deposition time durations. The influence of deposition time on film thickness and the optical characteristics of the films were investigated. The samples were annealed at elevated temperature (400 °C), and all the films were submitted to UV–vis spectrophotometry, FTIR and Raman measurements. The optical transmittance of the annealed film increases significantly, and at the same time, the reflection of the film decreases. The FTIR Spectra of as deposited and annealed samples show typical for NiO absorption bands. Raman spectra reveal peaks, related to phase crystalline modification.