EFFECT OF PHASE-SEPARATION ON PRECIPITATION CHARACTERISTICS OF CUCL QUANTUM DOTS IN THE BOROSILICATE GLASS SYSTEM

Effects of phase separation on the precipitation of CuCl particles in the sodium-borosilicate glass system have been investigated using acid elution measurement, UV/VIS absorption spectroscopy, and scanning and transmission electron microscopy. Compositions of 7.5Na(2)O-40B(2)O(3 )-52.5SiO(2) and 22.5Na(2)O(3)-40B(2)O(2)-37.5SiO(2) (wt%) were chosen as matrix glasses based on their phase separability and the relations hip between the phase separation of the glass matrix and the precipita tion of CuCl particles was studied. The CuCl precipitation occurred on ly in the phase-separable glass matrix and the radius of the CuCl nano crystals increased with heat treatment time. The CuCl crystals were pr ecipitated both in the boron-rich phase and in the silica-rich phase. Larger CuCl particles, with an average size of similar to 3.3 nm, than those in the silica-rich phase, which averaged similar to 1.7 nm, wer e observed to precipitate in the boron-rich phase. The observed CuCl p article size difference and the non-uniform distribution of the partic les are attributed to the fast growth of the CuCl particles due to the lower viscosity of the boron-rich phase compared to that in the silic a-rich phase.