Ortiz-Soto Lorna B, Alexeev Oleg S, Amiridis Michael D
Department of Chemical Engineering, University of South Carolina, Columbia, South Carolina 29208, USA.
Langmuir. 2006 Mar 28;22(7):3112-7. doi: 10.1021/la052358k.
The structural and catalytic properties of SiO2- and TiO2 -supported Pt-Au bimetallic catalysts prepared by coimpregnation were compared with those of samples of similar composition synthesized from a Pt2Au4(C{triple bond}CBut)8 cluster precursor. The smallest metal particles were formed when the bimetallic cluster was used as a precursor and TiO2 as the support. FTIR data indicate that highly dispersed Au crystallites in these samples, presumably located in close proximity to Pt, are capable of linearly coordinating CO molecules with a characteristic vibration observed at 2111 cm(-1). The cluster-derived Pt2Au4/TiO2 samples were the only ones exhibiting low-temperature CO oxidation activity, indicating that both the high dispersion of Au and the nature of the support are important factors affecting the catalytic activity for this system.
通过共浸渍法制备的SiO₂负载和TiO₂负载的Pt-Au双金属催化剂的结构和催化性能，与由Pt₂Au₄(C≡CBut)₈簇前驱体制备的组成相似的样品进行了比较。当使用双金属簇作为前驱体且TiO₂作为载体时，形成了最小的金属颗粒。傅里叶变换红外光谱(FTIR)数据表明，这些样品中高度分散的Au微晶，可能位于靠近Pt的位置，能够以在2111 cm⁻¹处观察到的特征振动线性配位CO分子。源自簇的Pt₂Au₄/TiO₂样品是唯一表现出低温CO氧化活性的样品，表明Au的高分散性和载体的性质都是影响该体系催化活性的重要因素。
