Global energy consumption is increasing dramatically. An International Energy Outlook report published in 2009 suggested that energy demand will grow by as much as 44 percent in the period 2006 to 2030 if current policies and laws remain unchanged. With economic recovery anticipated after 2010, a surge in energy demand is expected. So far, this demand could be met, in principle, from conventional energy sources, which are petroleum, coal, and natural gas. However, global supplies of fossil fuels are not limitless, and their combustion is clearly linked with ongoing changes to our planet's climate. Therefore, it is indispensable for us to explore a clean and reproducible energy source to maintain sustainable development of humans. Hydrogen is considered as a suitable alternative for the conventional energy sources since it is non-polluting and has great potential to be used for transportation purposes in fuel cells. Hydrogen is mainly produced today by steam reforming and thermal cracking of natural gas and coal gasification, which cannot alleviate the emission of green house gas. Fujishima and Honda reported that TiO2 photoelectrode can be used to split water under UV-light irradiation in 1972.1 Since this report, hydrogen generation from photocatalytic decomposition of water has attracted significant interest. Various semiconductor metal oxide photocatalysts have been studied during the past decade. Presently, ordered mesoporous materials which possess large internal surface area and long-range ordered mesoscale pores have attracted extensive attention.2-3 In our current project, we have successfully synthesized Ti-MCM-48 and Ti-MCM-41 mesoporous materials at room temperature by post-impregnation method and direct synthesis method, respectively. The physico-chemical properties of the Ti-MCM-48 and Ti-MCM-41 have been investigated using a wide selection of techniques ranging from X-ray Diffraction (XRD), Nitrogen Adsorption, Raman spectroscopy, and Diffuse Reflectance Spectroscopy. We have determined that Ti-MCM-48 and Ti-MCM-41 mesoporous materials can be used as the photocatalysts to generate hydrogen from photocatalytic splitting of water. It is believed that the method of preparation, particle size, crystal phase, and titanium coordination would affect the photocatalytic activity of those mesoporous materials. Currently, our efforts are directed towards understanding the local coordination and geometry of Ti in Ti-MCM-48 and Ti-MCM-41 mesoporous materials.
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