CO2 Photocatalytic Reduction by H2O On Pt/TiO2 Nonacomposite Catalyst

The CO₂ conversion to chemically valuable species is important in developing alternative fuels and various raw materials for different industries. It also aids in preventing the continuous rise in global temperature due to the green house effect of CO₂. In this paper a brief overview of the CO₂ chemical reduction is presented. Further, a gas-solid heterogeneous system (as shown in Figure 1) for solar-chemical energy conversion of CO₂-SCR (Selective Catalytic Reduction) with H₂O on various nanostructure photocatalysts is discussed, in which, the H₂O serves as hydrogen resource (or reducing agent) and CO₂ as carbon resource (or oxidant), UV/Visible light provides the reaction energy and the prorous semiconductor provides the active centers for such a photocatalysis process to ultilize the solar energy through chemical conversion or storage process. Last, various crystal phase (rutile or anatase) and size (2-20 nm) of low dementional nano-TiO₂ (particle, ribbon or tube) and Pt supported/composite photocatalysts are synthesized via the sol-gel and high temperature hydrothermal methods. The catalysts are characterized with powder X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), selected-area electron diffraction (SAED), photoluminescence and the photocatalytic reduction of CO₂ with H₂O to produce chemically valuable compound such as CH₄ or CH₃OH are among the most desirable and challenging goals.