Application of hot press sintering to Na2O-B2O3-SiO2 gels containing quantum dots for lowering of densification temperature

Na2O-B2O3-SiO2 (NBS) gels containing a large amount of CdS quantum-dots (10 wt%) were densified using the hot press (HP) sintering method. By HP treat ment, full-densification temperature could be lowered by about 40 degreesC than that of the normal non-pressing (NP) heat treatment. Exciton absorptio n of CdS quantum-dots in HP-sample showed a large blue shift compared with that in the NP sample, and the size-distribution of CdS dots remained very sharp, with a mean particle diameter d = 3.66 nm and a standard deviation o f sigma = 0.72. HP pressure had a large effect on the reduction of sinterin g temperature and time, resulting in the suppression of the aggregation and growth of CdS quantum-dots in NBS glasses.