Yi C-W, Luo K, Wei T, Goodman D W
Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, USA.
J Phys Chem B. 2005 Oct 6;109(39):18535-40. doi: 10.1021/jp053515r.
Pd, Au, and Pd-Au mixtures were deposited via physical vapor deposition onto a Mo(110) substrate, and the surface concentration and morphology of the Pd-Au mixtures were determined by low-energy ion scattering spectroscopy (LEISS), infrared absorption spectroscopy (IRAS), temperature-programmed desorption (TPD), and X-ray photoelectron spectroscopy (XPS). Pd-Au mixtures form a stable alloy between 700 and 1000 K with substantial enrichment in Au compared to the bulk composition. Annealing a 1:1 Pd-Au mixture at 800 K leads to the formation of a surface alloy with a composition Au(0.8)Pd(0.2) where Pd is predominantly surrounded by Au. The surface concentration of this isolated Pd site can be systematically controlled by altering the bulk Pd-Au alloy concentration.
通过物理气相沉积法将钯（Pd）、金（Au）以及钯 - 金混合物沉积到钼（Mo）（110）衬底上，并用低能离子散射光谱（LEISS）、红外吸收光谱（IRAS）、程序升温脱附（TPD）和X射线光电子能谱（XPS）来测定钯 - 金混合物的表面浓度和形态。钯 - 金混合物在700至1000K之间形成一种稳定合金，与整体成分相比，金有显著富集。在800K下对1:1的钯 - 金混合物进行退火处理会导致形成一种表面合金，其组成为Au(0.8)Pd(0.2)，其中钯主要被金包围。通过改变整体钯 - 金合金浓度，可以系统地控制这种孤立钯位点的表面浓度。
