ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Effect of Ag-doping of nanosized FeMgO system on its structural, surface, spectral, and catalytic properties

Sahar A. El-Molla, Laila I. Ali, Nabil H. Amin, Anwer A. Ebrahim, and Hala R. Mahmoud

Chemistry Department, Faculty of Education, Ain Shams University, Roxy, 11757 Cairo, Egypt

E-mail: saharelmolla@yahoo.com

Abstract: The effects of Ag-doping on the physico-chemical, spectral, surface, and catalytic properties of the FeMgO system with various Fe₂O₃ loadings were investigated. The dopant (Ag) molar ratio varied between 0.01 % and 0.05 %. The techniques employed for characterisation of catalysts were TG/DTG, XRD, ESR, N₂ adsorption at −196°C, and catalytic decomposition of H₂O₂ at 25–35°C. The results obtained revealed that the investigated catalysts consisted of nanosized MgO as the major phase, apart from the MgFe₂O₄ and/or Fe₃O₄ phases. ESR result of the FeMgO system revealed the presence of paramagnetic species as a result of Ag-doping. The textural properties including SBET, porosity and St were modified by Ag-doping. The doping process with Ag-species improved the catalytic activity of the FeMgO system. Increasing the calcination temperature from 400°C to 800°C increased the catalytic activity (k*_{30 °C}) of 0.05 AgFeMgO in H₂O₂ decomposition by 21.2 times.

Keywords: Fe₂O₃/MgO catalyst – Ag-doping – ESR – surface – paramagnetic – H₂O₂ decomposition

Full paper is available at www.springerlink.com.

DOI: 10.2478/s11696-012-0183-x

Chemical Papers 66 (8) 722–732 (2012)