Post-Synthesis of Ti-SBA-15 in Supercritical CO2-Ethanol Solution

Ti-SBA-15 materials with Ti incorporated into the framework of SBA-15 and controllable Ti contents were successfully prepared via a post-treatment route in supercritical CO 2 -ethanol solution, followed by calcination. The resultant Ti-SBA-15 materials were characterized by means of different techniques including X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, IR analysis, and N 2 orption analysis. It was demonstrated that the resultant materials retained a structure similar to that of the parent SBA-15, and Ti was incorporated into the framework of SBA-15. At high Ti content, i.e, Si/Ti = 5:1, a TiO 2 phase formed and was coated onto the inner surface of SBA-15 in addition to the incorporation of the Ti in the framework. The BET surface areas of the Ti-SBA-15 samples decreased with increasing Ti content. The presence of small amounts of H 2 0 in the reaction medium may have resulted in some TiO 2 nanoparticles being uniformly distributed in the pores of the SBA-15 accompanying the incorporation ofTi in the SBA-15 framework.