Erschienen in:
Journal of the American Ceramic Society, 95 (2012) 3, Seite 1042-1047
Sprache:
Englisch
DOI:
10.1111/j.1551-2916.2011.04932.x
ISSN:
1551-2916;
0002-7820
Entstehung:
Anmerkungen:
Beschreibung:
<jats:p>Intense infrared emission of <jats:styled-content style="fixed-case"><jats:roman>Yb<jats:sup>3+</jats:sup></jats:roman></jats:styled-content> is reported for the <jats:styled-content style="fixed-case"><jats:roman>Eu<jats:sup>3+</jats:sup>/Yb<jats:sup>3+</jats:sup></jats:roman></jats:styled-content> co‐doped fluorosilicate glass ceramics. With annealing methods, cubic <jats:styled-content style="fixed-case"><jats:roman>SrF<jats:sub>2</jats:sub></jats:roman></jats:styled-content>:<jats:styled-content style="fixed-case"> <jats:roman>Eu<jats:sup>3+</jats:sup>, Yb<jats:sup>3+</jats:sup></jats:roman></jats:styled-content> nanocrystals are precipitated homogeneously in the glass ceramics. The incorporation of <jats:styled-content style="fixed-case"><jats:roman>Eu<jats:sup>3+</jats:sup></jats:roman></jats:styled-content> and <jats:styled-content style="fixed-case"><jats:roman>Yb<jats:sup>3+</jats:sup></jats:roman></jats:styled-content> in the <jats:styled-content style="fixed-case"><jats:roman>SrF<jats:sub>2</jats:sub></jats:roman></jats:styled-content> nanocrystal was confirmed by <jats:styled-content style="fixed-case">XRD</jats:styled-content> patterns and emission spectra. Deriving from much closer distance between <jats:styled-content style="fixed-case"><jats:roman>Eu<jats:sup>3+</jats:sup></jats:roman></jats:styled-content> and <jats:styled-content style="fixed-case"><jats:roman>Yb<jats:sup>3+</jats:sup></jats:roman></jats:styled-content> ions in the nanocrystals, higher efficient energy transfer of <jats:styled-content style="fixed-case"><jats:roman>Eu<jats:sup>3+</jats:sup></jats:roman></jats:styled-content>→<jats:styled-content style="fixed-case"><jats:roman>Yb<jats:sup>3+</jats:sup></jats:roman></jats:styled-content> (cross relaxation between <jats:styled-content style="fixed-case"><jats:roman>Eu<jats:sup>3+</jats:sup></jats:roman></jats:styled-content>:<jats:sup>5</jats:sup>D<jats:sub>0</jats:sub>→<jats:sup>7</jats:sup>F<jats:sub>6</jats:sub> and<jats:styled-content style="fixed-case"><jats:roman>Yb<jats:sup>3+</jats:sup></jats:roman></jats:styled-content>:<jats:sup>2</jats:sup>F<jats:sub>5/2</jats:sub>→<jats:sup>2</jats:sup>F<jats:sub>7/2</jats:sub> transition or cooperative energy transfer from one <jats:styled-content style="fixed-case"><jats:roman>Eu<jats:sup>3+</jats:sup></jats:roman></jats:styled-content> ion to a couple of <jats:styled-content style="fixed-case"><jats:roman>Yb<jats:sup>3+</jats:sup></jats:roman></jats:styled-content> ions) and intense near infrared emission of <jats:styled-content style="fixed-case"><jats:roman>Yb<jats:sup>3+</jats:sup></jats:roman></jats:styled-content>:<jats:sup>2</jats:sup>F<jats:sub>5/2</jats:sub>→<jats:sup>2</jats:sup>F<jats:sub>7/2</jats:sub> transition are achieved in the glass ceramics. Both the quantum yield (<jats:styled-content style="fixed-case">QY</jats:styled-content>) and the <jats:styled-content style="fixed-case">NIR</jats:styled-content> emission intensity of the glass ceramics are enhanced, when compared with the precursor glasses. The maximum <jats:styled-content style="fixed-case">ET</jats:styled-content> efficiency of <jats:styled-content style="fixed-case"><jats:roman>Eu<jats:sup>3+</jats:sup></jats:roman></jats:styled-content>→<jats:styled-content style="fixed-case"><jats:roman>Yb<jats:sup>3+</jats:sup></jats:roman></jats:styled-content> is close to 60%, and the measured maximum <jats:styled-content style="fixed-case">QY</jats:styled-content> of 980 nm emissions is 13%. It demonstrates the potential application of <jats:styled-content style="fixed-case"><jats:roman>Eu<jats:sup>3+</jats:sup>/Yb<jats:sup>3+</jats:sup></jats:roman></jats:styled-content> co‐doped glass ceramics in improving the efficiency of silicon solar cells.</jats:p>