Electrochromism in some thinhyphen;film transitionhyphen;metal oxides characterized by xhyphen;ray electron spectroscopy

摘要

Qualitative results of an xhyphen;ray photoelectron and optical investigation of three thinhyphen;film transitionhyphen;metal oxides, namely, WO3, MoO3, and V2O5are reported. Data were obtained on films that werenotcoloredandcoloredby an electrochromic process. The particular electrochromic coloration process used is electrolytic in nature and employs a sandwichhyphen;structure electrochromic cell and electrolyte pool. The optical spectra show increased absorption in the visible (red) and nearhyphen;infrared spectral regions upon coloration. The photoelectron spectra forcoloredfilms exhibit a small band near the Fermi level and asymmetric band shapes for metal corehyphen;level bands which are absent in films that arenotcolored. The new band and the asymmetric band shapes are attributed to the presence of a reducedhyphen;state species caused by the presence of trapped electrons and metal bronze formation. Results from coloration with different electrolyte pools, i.e., H+, Li+, Na+, K+, Cs+, and Mg2+electrolytes, are reported.