|a英文題名:Prepared Pd-Au/TiO2-WO3 Nanoparticle Applied in Photoreduction of CO2 into CO and CH4
|a本研究使用水熱法和溶膠凝膠兩種方法製備Pd-Au/TiO2-WO3納米顆粒作為光還原二氧化碳的光觸媒。使用X光繞射儀(XRD)，描式電子顯微鏡(SEM)，穿透式電子顯微鏡(TEM)，X光光電子能譜儀(XPS)，BET，UV-vis，光致發光光譜儀（PL）對製備的鑑定。與市售TiO2(P25)相比，在TiO2-WO3複合材料加入適量的Pd和Au會有較高的光還原活性。CH4產率(39.1 μmol g-1 h-1)是TiO2 (P25)的100倍；除此之外，還產出有大量的CO (271.3 μmol g-1 h-1)是TiO2 (P25)的300倍。光催化活性的大幅提高可能來自比表面積的增加(72.9 m2 g-1)，及在可見光吸收的增加。摻入Pd-Au於TiO2也提高了太陽能的利用率及減少Pd-Au/TiO2-WO3複合材料電子電洞對再結合的機會而提高光還原活性。CH4產量的量子產率計算為(1.05 %)。最後在Pd-Au / TiO2-WO3的光還原反應中提出了CO2的還原反應機構，而本研究可以為TiO2應用於太陽能轉換和儲存等帶來新的發展。|uThis study presents Pd-Au/TiO2-WO3 nanoparticle prepared by a hydrothermal and sol-gel method as a CO2 conversion photocatalysts. The catalysts were characterized by X-ray diffraction (XRD), Scan electron microscope (SEM), Tunneling electron microscope (TEM), XPS, BET, UV-visible and Photoluminescence (PL) instruments. The appropriate amounts of Pd and Au on TiO2-WO3 composites exhibited enhanced photocatalytic activity for CO2 reduction compared with commercial TiO2 (P25). It showed the photocatalytic CH4 production rate (39.1 μmol g-1 h-1) was 100 fold that of TiO2 (P25); moreover, a large amount of CO was produced (at a rate of 271.3 μmol g-1 h-1) was 300 fold that of TiO2 (P25). The significantly improved photocatalytic activity was not only due to the increased specific surface area (72.9 m2g-1) but also UV-vis showed a remarkable enhancement of light absorption. It owes to the incorporation Pd-Au with TiO2 the visiblelight active the UV light-responsive for increased solar energy utilization. Furthermore, PL spectra revealed that the Pd-Au content can influence the charge transfer efficiency of the Pd-Au/TiO2-WO3 composites. The quantum yield of CH4 production was calculated as 1.05 %. A CO2 reduction reaction mechanism was proposed on Pd-Au/TiO2-WO3. This study can bring new insights into designing TiO2 nanostructures for applications such as solar energy conversion and storage.
|aPrepared Pd-Au/TiO2-WO3 Nanoparticle Applied in Photoreduction of CO2 into CO and CH4