Alternative method for preparation of Au/TiO2 with precise Au0/Auδ+. Issue 7 (1st October 2015)

• Record Type: Journal Article
• Authors: Du, Mingming; Huang, Jiale; Jing, Xiaolian; Sun, Daohua; Li, Qingbiao
• Is Part Of: Journal of chemical technology & biotechnology. Volume 91:Issue 7(2016:Jul.)
• Page Start: 2125
• Page End: 2130
• Publication Date: 2015-10-01
• Subjects: Au/TiO2 catalysts -- Au nanoparticles -- Au valence -- CO oxidation; Biotechnology -- Periodicals; Chemistry, Technical -- Periodicals; Chemical engineering -- Periodicals; Industries -- Environmental aspects -- Periodicals; 660
• DOI: 10.1002/jctb.4815
• Languages: English
• ISSNs: 0268-2575

Abstract

Abstract: BACKGROUND: Au valence for Au catalysts has been considered a vital parameter for catalytic activity towards CO oxidation. However, there is no effective method to prepare precise Au 0 /Au δ+ molar ratios with the same Au nanoparticles (NPs) sizes. RESULTS: A series of Au/TiO2 catalysts with tuneable Au 0 /Au δ+ molar ratios were prepared by the combination of a biosynthesis method and a deposition–precipitation (DP) method, and characterized by XPS, TEM, DRUV‐Vis techniques. First, biosynthesized metallic Au NPs were immobilized onto TiO2 supports to obtain Au/TiO2 catalysts with different Au loadings but with the same sized Au NPs. And then positively ionized Au species were supported onto the above Au/TiO2 catalysts by a DP method. The metallic Au and positively ionized Au species could be totally supported on the support. Therefore, the Au 0 /Au δ+ molar ratios could be controlled exactly. Compared with Au/TiO2 catalysts with metallic and positively ionized Au species alone, the catalyst Au/TiO2 ‐1:1 showed the best initial catalytic activity, suggesting enhanced catalytic performance due to the coexistence of Au 0 and Au δ+ . CONCLUSION: This study verifies that Au/TiO2 catalysts with accurate Au 0 /Au δ+ molar ratios can be prepared by a combination of biosynthesis and a DP method. © 2015 Society of Chemical Industry