Blue light emission in mesoporous SiOx nano-structure

Mesoporous silicon oxide (SiOx) nano-structure has been synthesized from tetraethyl orthosilicate (TEOS) with a two-step method: sol-gel with the hydrolysis of TEOS and solvent-thermal process. Observations using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) show that the mesoporous nano-materials are sponge-like and meshes of them have a uniform diameter of about 15 nm. High-resolution transmission electron microscopy (HRTEM) reveals that the sample has two states: crystal silicon and amorphous SiOx. Energy dispersed X-ray spectrometry (EDAX) indicates that this structure is composed of Si and O elements and atomic ratio of Si:O is about 1:1.4. The photoluminescence (PL) measurements were carried out and show that the SiOx mesoporous structure has a stable and intensive blue emission. This nano-structure may have potential applications in future integrated optical devices. (C) 2007 Published by Elsevier Inc.