Silica-Supported Au Nanoparticles Decorated by TiO2: Formation, Morphology, and CO Oxidation Activity

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• 作者：Anita Horv&aacute ; th ; Andrea Beck ; Antal S&aacute ; rk&aacute ; ny ; Gyö ; rgyi Stefler ; Zsolt Varga ; Olga Geszti ; Lajos Tó ; th ; L&aacute ; szló ; Guczi
• 刊名：Journal of Physical Chemistry B
• 出版年：2006
• 出版时间：August 10, 2006
• 年：2006
• 卷：110
• 期：31
• 页码：15417 - 15425
• 全文大小：1060K
• 年卷期：v.110,no.31(August 10, 2006)
• ISSN：1520-5207

文摘

Au-TiO₂ interface on silica support was aimed to be produced in a controlled way by use of Au hydrosol.In method A, the Au colloids were modified by hydrolysis of the water-soluble Ti(IV) bis(ammoniumlactato)dihydroxide (TALH) precursor and then adsorbed on Aerosil SiO₂ surface. In method B, Au sol was firstdeposited onto the SiO₂ surface and then TALH was adsorbed on it. Regular and high-resolution transmissionelectron microscopy (TEM and HRTEM) and energy dispersive spectrometry (EDS) analysis allowed us toconclude that, in method A, gold particles were able to retain the precursor of TiO₂ at 1.5 wt % TiO₂ loading,but at 4 wt % TiO₂ content the promoter oxide appeared over the silica surface as well. With method B,titania was detected on silica at each TiO₂ concentration. In Au-TiO₂/SiO₂ samples, the stability of Auparticles against sintering was much higher than in Au/TiO₂. The formation of an active Au-TiO₂ perimeterwas proven by the greatly increased CO oxidation activity compared to that of the reference Au/SiO₂.