Synthesis, microstructure and thermal properties of photoluminescent hydrogenated amorphous silicon oxide nanopowders

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 (Si3–Si–H) dispersed in amorphous silica matrix (OSi2–Si–H, O2Si–Si–H) in the presence of silanol groups (Si–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 650 °C and formed a single crystal at 1000 °C.