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

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.

Improvement of physicochemical properties of Fe2O3/MgO nanomaterials by hydrothermal treatment for dye removal from industrial wastewater

“…The sample was prepared by impregnation of a known amount of finely powdered magnesium hydroxide, which was prepared previously [26], with an aqueous solution containing a known amount of iron nitrate dissolved in the least amount of bi-distilled water necessary to make a paste. The resulting paste was dried at 110°C and then calcined at 500°C for 4 h. The composition of the sample prepared was nominated as FeMgO IM .…”

“…1(a) and Table 1. It was clearly noticed that the XRD diffractogram of the FeMgO IM sample contained peaks due to MgO phase (periclase) (JCPDS 4-829) with a moderate degree of ordering [26]. The XRD diffractogram of FeMgO Co sample contained peaks of MgO phase with very low degree of crystallinity.…”

INFLUENCE OF Cu2+-DOPED FeMgO NANOMATERIALS ON THE DEHYDROGENATION AND DEHYDRATION OF ETHANOL

“…The surface texture of FeMgO catalysts were previously investigated by two of authors [11] and the most important results were reported as followings: i) the addition of a small amount of Fe2O3 to the MgO support followed by calcination at 500 o C resulted in an increase in SBET of hematite. The increase in the Fe2O3 molar content to 10 mol% is accompanied by a limited decrease in SBET.…”

The Effect of Transition Metal Oxide Dopants on the Structure, Morphology, Surface Texture and Catalytic Properties of FeMgO Nanomaterials Towards Dehydrogenation and Aldol Condensation Reactions

“…Therefore, supporting iron oxide usually results in modification of its textural, structural, and catalytic properties [4]. It is known that the activity and selectivity of a large variety of catalysts can be modified by loading them on a fine support and doping them with certain foreign oxides [6].…”

“…It has been reported that Fe 2 O 3 /MgO nano-composite prepared by impregnation, coprecipitation and hydrothermal have biomedical, catalytic and magnetic applications [4,11]. It was reported that doping the catalytic system with certain foreign oxides is accompanied by significant modifications in its thermal stability, surface, and catalytic properties [6]. It has been reported that doping the magnetite with chromium ions has a remarkable effect on its crystallinity, surface area, porosity and magnetic properties.…”