Nishimura, A.Inoue, T.Sakakibara, Y.Hirota, M.Koshio, A.Kokai, F.Hu, E.2019-10-272019-10-272019AIMS Materials Science, 2019; 6(4):464-4832372-04842372-0484http://hdl.handle.net/2440/121697This study investigated the optimum moral ratio of CO₂ and reductants H₂O and H₂ to obtain high CO₂ reduction performance of Pd/TiO₂ photocatalyst. The Pd/TiO₂ film photocatalyst is prepared by sol-gel and dip-coating process to form TiO₂ film and by pulse arc plasma method to dope Pd. The prepared Pd/TiO₂ film was characterized by SEM, EPMA and EELS. The impact of overlapping two Pd/TiO₂ films on CO₂ reduction performance was also investigated to utilize the light and prepared photocatalyst more effectively. Moreover, this study investigated the characteristics of Pd/TiO₂ film to reduce CO₂ under the illumination condition of Xe lamp with or without ultraviolet (UV) light. It is found when the moral ratio of CO₂/H₂/H₂O is set at 1:0.5:0.5, the best CO₂ reduction performance has been obtained under the illumination conditions of Xe lamp with and without UV light. It is revealed that the moral quantity of CH₄ per weight of photocatalyst for overlapped Pd/TiO₂ film is 8.14 μmol/g for the moral ratio of CO₂/H₂/H₂O of 1:0.5:0.5 under the illumination condition of Xe lamp with UV light, which is approximately 1.1 times larger than that for one Pd/TiO₂ film. It can be concluded that the optimum moral ratio of CO₂/H₂/H₂O, for the CO₂ reduction reaction, is 1:0.5:0.5.en© 2019 the Author(s), licensee AIMS Press. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0)Pd/TiO₂ photocatalyst; CO₂ reduction; overlapping effect; reductantJournal article003012486010.3934/matersci.2019.4.4642-s2.0-85068553960481047Hu, E. [0000-0002-7390-0961]