Synthesis and Characterization of γ-Alumina-Supported Cobalt and Iron Nanocatalysts

Abstract:

The present work deals with the synthesis of cobalt monometallic and bimetallic Co/Fe nanocatalysts supported on alumina. The nanocatalysts were prepared by a wet impregnation method. The samples were characterized in terms of reducibility, dispersion, metal particle size, textural characteristics and crystallinity. These characteristics were revealed using hydrogen temperature-programmed reduction (TPR), CO-chemisorption, transmission electron microscopy (TEM), X-ray diffraction (XRD) and nitrogen adsorption analysis. H₂-TPR analysis of Co/Al₂O₃ indicated three temperature regions at 507 ^◦C (low temperature), 650 ^◦C (medium temperature) and 731 ^◦C (high temperature) while characteristic peaks of Fe/ Al₂O₃ appeared at 454 ^◦C, 635 ^◦C and 716 ^◦C, respectively. Bimetallic nanocatalysts exhibited different physicochemical properties than those of the monometallic nanocatalysts. The incorporation of iron into cobalt nanocatalysts up to 50% of the total metal loaded enhanced the reducibility, increased the CO and H₂ chemisorbed and degree of reduction (DRT) while surface area decreased, further increase in the iron content resulted in a decrease in the crystallinity, increase in the average metal particle size and shift in the reduction towards higher temperatures.

• Periodical: Advanced Materials Research (Volume 545)
• Pages: 129-136
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.545.129
• Online since: July 2012
• Authors: Sardar Ali, Noor Asmawati Mohd Zabidi, Duvvuri Subbarao
• Keywords: Bimetallic Nanoparticles, Cobalt, Iron

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