Abstract

Electrochromic (EC) behaviours of nickel oxide (NiOx) thin films, grown by chemical process in a nickel ammine complex solution [Ni(NH3)x2+] after electrolysis of this solution (EL–C method), were investigated using various alkaline electrolyte solutions; potassium borate buffer (pH 12), KOH (pH 12.9), (CH3)4NOH and (C2H5)4NOH. The fully oxidized films in all adopted electrolytes commonly showed broadened UV–VIS spectra in the visible and near IR region. However, voltammetry studies associated with photoabsorption of the films revealed an apparent difference in the EC dynamics among the electrolytes caused by the variation of cation sizes and electrolyte solution pH. Characterization of as-prepared, oxidized and reduced films in the electrolytes by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were performed to explain the mechanism of the films based on the conversion between layered α-Ni(OH)2 and γ2-2NiO2·NiOOH. A model according to the extraction/insertion of cations or water molecules from/into the interlayer was proposed.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.