Study of photoreduction of CO 2 on yttrium and copper co-doped TiO 2 nanoparticles

Yttrium and copper co-doped TiO 2 catalysts were prepared by sol-gel method. The photocatalysts were characterized by means of XRD. By co-doping of Y 3 and Cu 2 not only could restrain the growth in size and aggregation of the nanoparticles, but also could effectively inhibit phase transformation from anatase phase to rutile. The reduction of CO 2 showed that the nano Y-Cu/TiO 2 obtained obvious photocatalytic reduction activity compared with bare TiO 2. When the addition of yttrium to TiO 2 reached 0.1wt.%, it got the highest activity, producing 126.60mol/gcat. of formaldehyde during 6 h reaction under the irradiation of 365nm UV light. However, the reduction efficiency of CO 2 on Y-Cu/TiO 2 was lower compared with Cu/TiO 2 and Y/TiO 2 catalysts because of resistance effects. Mechanism of CO 2 photocatalytic reduction on Y-Cu/TiO 2 catalyst was proposed. © 2011 IEEE.