Sol-gel-derived potassium-based di-ureasils for "smart windows''

• Sol-gel-derived KCF3SO3-doped di-urea cross-linked poly(oxyethylene) (POE)/siloxane (di-ureasil) ormolytes with infinity > n >= 1 (n is the number of oxyethylene units per K+ ion) have been analysed. Samples with n. 40 are thermally stable up to 310 degrees C. At n >= 100, POE crystallites are present. At n = 5, a crystalline POE-KCF3SO3 complex with stoichiometry 1 : 1 is formed. In the xerogel with n = 1 this complex coexists with free salt. The highest ionic conductivity is reached at n = 20. The redox stability domain of this material spans 5.0 V. "Free'' anions and weakly coordinated CF3SO3- ions appear to be the main charge carriers at n = 20. The K+ ions interact with the urea carbonyl oxygen atoms at all salt concentrations. Complexation of the cations by POE occurs at n

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Annan teknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Other Engineering and Technologies (hsv//eng)

Keyword

POLYMER ELECTROLYTES

ENVIRONMENT

SALTS

STATE

TEMPERATURE

FILMS

SPECTRA

ORMOLYTES

TRIFLATE

IONIC-CONDUCTIVITY

Publication and Content Type

art (subject category)

ref (subject category)