کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
56140 47074 2011 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Preparation and characterization of silica-supported, group IB–Pd bimetallic catalysts prepared by electroless deposition methods
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی کاتالیزور
پیش نمایش صفحه اول مقاله
Preparation and characterization of silica-supported, group IB–Pd bimetallic catalysts prepared by electroless deposition methods
چکیده انگلیسی

Electroless deposition has been used to synthesize a series of Au–, Ag–, and Cu–Pd/SiO2 bimetallic catalysts having incremental surface coverages and compositions of each group IB metal. Thermodynamically unstable, yet kinetically stable, electroless bath(s) were developed using metal bis-cyano salts of the group 1B metal and N2H4 (for Au and Ag) or DMAB (for Cu) as reducing agents. The times (∼1–2 h) and profiles (1st order in group 1B metal concentration) observed for complete deposition indicate good kinetic control of the electroless deposition process. The bimetallic catalysts have been characterized using selective chemisorption, atomic absorption spectroscopy (AAS), Fourier transform infrared spectroscopy (FTIR) of adsorbed CO, and X-ray photoelectron spectroscopy (XPS) techniques. Decreases in Pd surface sites with addition of IB metals confirm deposition onto the supported Pd nanoparticle surfaces. FTIR studies suggest that deposition of Cu and Ag are selective towards Pd(1 1 1) sites, while Au deposits non-discriminately on all Pd sites. Finally, XPS measurements for each family of bimetallic catalysts suggest a net electron transfer from the Pd to the deposited metal.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Catalysis Today - Volume 160, Issue 1, 2 February 2011, Pages 170–178
نویسندگان
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