Post annealing immersion: A new technique for studying rare earth ions in porous materials

Autor: A.J. Silversmith, K.R. Hoffman, K. E. Arpino, D.M. Boye
Rok vydání: 2011
Předmět:
Zdroj: Journal of Luminescence. 131:453-456
ISSN: 0022-2313
Popis: A novel technique is introduced for studying how rare earth ions are incorporated into the matrix of porous materials. Tb 3 + -doped silica sol-gel is annealed to form porous glass and immersed in an aqueous Gd(NO 3 ) 3 solution. Re-heating removes the liquid and deposits Gd 3+ ions on the internal pore surfaces. Spectroscopic investigation of Gd 3+ → Tb 3+ energy transfer yields information about the location of Tb 3+ dopant ions relative to pore surfaces. Results from post-annealing immersion experiments indicate that most Tb 3+ dopant ions are close to pore surfaces when sol-gel glass is annealed to 700 °C. The observed energy transfer decreases with higher annealing temperatures, indicating that Tb 3+ dopants in densified regions are isolated from Gd 3+ ions deposited on pore surfaces. Al 3+ co-doping affects both the overall sample density and the degree of Gd 3+ → Tb 3+ interaction in post-annealing immersion samples.
Databáze: OpenAIRE