Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
74624 | Microporous and Mesoporous Materials | 2011 | 6 Pages |
In this study, mesoporous titania with high surface area and pore volume was simply and eco-friendly synthesized from titania nanosphere–sucrose nanocomposites without any kinds of surfactant templates, and we first report that environmentally friendly sucrose plays an important role as a nonsurfactant template for synthesis of mesoporous titania. The amorphous titania nanosphere–sucrose nanocomposites were formed by simply dissolving sucrose in the 8 nm-sized titania sol at room temperature and drying the sol. After calcination of the nanocomposites, the mesoporous titania with three-dimensionally interconnected wormhole mesostructure was successfully obtained along with formation of nanocrystal framework. The pore size of the mesoporous titania was easily controlled from 3.3 nm up to 7.1 nm by simply changing the sucrose concentration in the nanocomposite sol. In addition, we investigated effect of a pre-calcination process under vacuum on the thermal stability of the mesoporous titania. The pre-calcination was conducted prior to a calcination process in air for elimination of templates, and nonporous titania-carbon nanocomposites were formed during the pre-calcination process under vacuum. As a result, mesostructure of the mesoporous titania prepared without the pre-calcination process totally collapsed at 700 °C, whereas the mesoporous titania synthesized with the pre-calcination process maintained its mesostructure up to 800 °C. The improved thermal stability is attributed to the titania nanocrystal framework preformed among rigid carbon template networks during the pre-calcination process, leading to mild crystalline growth and slow anatase–rutile transformation during the calcination process for template removal.
Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideResearch highlights► Mesoporous titania was simply synthesized from titania nanosphere–sucrose nanocomposites. ► Sucrose plays an important role as a nonsurfactant template for synthesis of mesoporous titania. ► The pore size of the mesoporous titania was easily controlled from 3.3 nm up to 7.1 nm. ► The improved thermal stability is attributed to the titania nanocrystal framework preformed during the pre-calcination.