Impact of Pd Loading on CO(2) Reduction Performance over Pd/TiO(2) with H(2) and H(2)O

This study investigated the impact of molar ratio of CO(2) to reductants H(2)O and H(2), as well as Pd loading weight on CO(2) reduction performance with Pd/TiO(2) as the photocatalyst. The Pd/TiO(2) film photocatalyst is prepared by the sol-gel and dip-coating process to prepare TiO(2) film and the pulse arc plasma method is used to dope Pd on TiO(2) film. The prepared Pd/TiO(2) film was characterized by SEM, EPMA, STEM, EDS, and EELS. This study also investigated the performance of CO(2) reduction under the illumination condition of Xe lamp with or without ultraviolet (UV) light. As a result, it is revealed that when the molar ratio of CO(2)/H(2)/H(2)O is set at 1:0.5:0.5, the best CO(2) reduction performance has been obtained under the illumination condition of Xe lamp with and without UV light. In addition, it is found that the optimum Pd loading weight is 3.90 wt%. The maximum molar quantities of CO and CH(4) produced per unit weight of photocatalyst are 30.3 μmol/g and 22.1 μmol/g, respectively, for the molar ratio of CO(2)/H(2)/H(2)O = 1:0.5:0.5 under the condition of Xe lamp illumination with UV light. With UV light, C(2)H(4) and C(2)H(6), as well as CO and CH(4) are also produced by the Pd/TiO(2) film photocatalyst prepared in this study.