摘要
The mesoporous titanium oxides- and carbide-carbon nanocomposites (Ti-C nanocomposites) with different morphologies at various Ti/C mass ratios were directly synthesized via supramolecular self-assembly with in situ crystallization process. The microstructures including surface area, morphology, and crystallinity were characterized by surface area analyzer, TEM, and SAXS/ XRD, respectively. The specific BET surface areas (178-639 m 2 g -1 ), micropore surface areas (6.3-47.3%), and total pore volumes (0.18-0.46 cm 3 g -1 ) increase with the increase in calcination temperatures and Ti/C mass ratios. The calcination temperature and carbon content have significant effect, on the thermal stability of titanium-based nanomaterials. The crystallinity changes from anatase, rutile, Magneli phases, and. then to TiC when the carbon content is lower than 35 wt %, while the crystal phase of Ti-C composites at 50 wt % changes directly from anatase to TiC. However, Mageli products lose the mesostructures. The sizes Of TiO 2 nanocrystals are in the range 2.6-9.7 nm, and. increase with increasing temperature to slightly distort the ordered mesostructured regularity up to 800 °C, and low distorted octahedrons with 6-fold coordinated titanium carbide are formed at 1000 °C. In addition, the graphitized carbons, determined by sp 2 - and sp 3 -bonded carbon contents from XAS spectra, increased upon increasing calcination temperature, depicting the increase in graphitization after calcination. Results obtained in this study allow us to elucidate the micro-structural changes of titanium-based materials inside the highly ordered mesoporous carbon matrices and open an avenue to the design and synthesis of a multitude of cooperatively functional organic-inorganic materials with attractive novel properties. © 2010 American Chemical Society.