Hydrogenated amorphous silicon oxide photoluminescent nanopowders have been synthesized using a simple solution method involving the reaction of lithium with trichlorosilane in tetrahydrofuran at room temperature. The powders exhibited maximum luminescent peak at 1.1 eV and had an average composition of SiO0.92H0.53. They possess inhomogeneous microstructures that contain a-Si clusters (Si-3-Si-H) dispersed in amorphous silica matrix (OSi2-Si-H, O2Si-Si-H) in the presence of silanol groups (equivalent toSi-OH). DTA, TGA and FTIR analyses showed that the Si-H bond was broken at 150 C and the hydrogen desorption reached a maximum around 300 C. The a-Si clusters started to crystallize at 650degreesC and formed a single crystal at 1000 degreesC. (C) 2002 Elsevier Science B.V. All rights reserved.