PREPARATION OF ND-DOPED SILICA GLASSES BY THE SOL-GEL METHOD

Monolithic NdAl co-doped silica glasses were prepared by the sol-gel method with double metal alkoxide of neodymium and aluminum, and their fluorescence properties were evaluated and compared with those of Nd-doped silica glasses. The dispersibility of Nd3+ in the NdAl co-doped silica glasses increases significantly because the structure of the double metal alkoxide is maintained until the final glassy state, with a higher Nd concentration of up to 4 mol% as Nd2O3. It was found that concentration quenching caused by clustering of Nd3+, as shown in the case of glasses with a relatively higher Nd concentration, was controlled. Aerogel prepared with a CO2 extractor had the merit of removing the OH groups. Because of the large pore size and the resultant higher densification temperature, a relatively longer fluorescent lifetime was observed. © 1990.