Electrochromic vanadium pentoxide
- EIC Labs., Inc., Norwood, MA (United States)
Vanadium pentoxide films exhibit a complex electrochromic response. On lithium intercalation the optical absorption edge of V{sub 2}O{sub 5} is shifted to higher energies by 0.2--0.31 eV. The shift in absorption edge results in a yellow to colorless modulation as the films become increasingly transparent in the blue. There is a concurrent decrease in transmittance in the near-infrared which causes the V{sub 2}O{sub 5} film to develop a bluish color at intercalation levels greater than {approximately} 15 mC/cm{sup 2}. The relative contribution of the blue-UV and near-infrared optical modulation depends on the thickness of the film and coloration efficiencies based on a Beer`s law relationship between optical density and charge injection do not accurately describe the electrochromic response. If an appropriate film thickness is chosen, typically around 120 nm, V{sub 2}O{sub 5} exhibits a yellow to colorless modulation on 10--15 mC/cm{sup 2} of lithium insertion. The V{sub 2}O{sub 5} film can therefore act as a counter electrode to WO{sub 3} in a variable transmittance electrochromic device.
- OSTI ID:
- 86088
- Report Number(s):
- CONF-8809123-; ISBN 0-8194-0069-6; TRN: IM9534%%160
- Resource Relation:
- Conference: International congress on optical science and engineering, Hamburg (Germany), 13-23 Sep 1988; Other Information: PBD: 1990; Related Information: Is Part Of Large-area chromogenics: Materials and devices for transmittance control. Volume IS 4; Lampert, C.M. [ed.] [Lawrence Berkeley Lab., CA (United States)]; Granqvist, C.G. [ed.] [Chalmers Univ. of Technology and Univ. of Gothenburg, Gothenburg (Sweden)]; PB: 618 p.
- Country of Publication:
- United States
- Language:
- English
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