Development of Iron Doped Manganese oxide (Mn_(2-x)Fe_xO_3) Catalysts for Soot Oxidation Applications

摘要

This work deals with the catalytic soot oxidation using pure Manganese (III) oxide and Iron doped Mn_2O_3 catalysts. The compounds Mn_2O_3 and the Iron (Fe) doped oxide series Mn_(2-x)Fe_xO_3 were synthesized using the method of coprecipitation. All the materials fabricated were characterized using XRD, BET, XPS and SEM analysis. XRD analysis has clearly confirmed the formation of solid solution in all the Fe doped catalysts (till x=0.2). Presence of multiple oxidation states in both Mn and Fe was noted in the prepared samples using XPS analysis. This redox ability of both Mn and Fe has increased the number of oxygen vacancies in Mn_(2-x)Fe_xO_3 samples. The Higher amount of adsorbed oxygen is noted in the sample with x=0.2. SEM analysis showed that increase in Fe doping has increased the porosity of the samples. The activity of oxidation of soot by the catalysts was evaluated with instrumental TGA analysis where soot and the synthesized catalyst were in tight contact. Amongst the synthesized catalysts Mn_(1.8)Fe_(0.2)O_3 exhibited better catalytic performance due to good porous structure and surface area along with the presence of higher oxygen vacancies.