新的溶胶-凝胶法制备Ge/SiO_2量子点玻璃

Preparation of Quantum-dot Ge Doped SiO_2 Glass by a New Sol-gel Process

以 3-三氯锗丙酸和正硅酸乙酯为原料 ,通过水解、缩聚凝胶热处理及氢气反应 ,在 Si O2 凝胶玻璃中析出立方相 Ge纳米晶 ,当 x=30时 ,凝胶玻璃中除了析出立方相 Ge纳米晶外 ,还析出六方相 Ge O2 .利用XRD测试了 Ge纳米晶的大小 ,发现随着掺杂量的增加 ,纳米颗粒粒径从 1 nm增大到 1 0 nm.电子衍射表明镶嵌在 Si O2 凝胶玻璃中的

Ge nanocrystals embedded in SiO\-2 gel\|glasses were prepared by a sol\|gel method. The gels synthesized through the hydrolysis of a complex solution of Si(OC\-2H\-5)\-4 and Cl\-3GeCH\-2CH\-2COOH were heated at 600 ℃ in air, and then heated from 500 to 700 ℃ in H\-2, in which Ge\+\{4+\} ions were reduced to precipitate Ge cubic crystals. However,Ge cubic as well as GeO\-2 hexagonal crystals were formed in SiO\-2 matrix when \%n\%(GeO\-2)/\%n\%(SiO\-2)=0\^30. The size of Ge nanocrystals, determined from the line broadening of X\|ray diffraction pattern, increases from 1 to 10 nm in diameter with molar ratios of GeO\-2/SiO\-2 increasing. The Ge nanocrystals were found to be polycrystalline in the SiO\-2 gel\|glasses by electron diffraction pattern.