**Abstract**

Soot has been the cause of global warming since the dawn of diesel engines. Soot oxidation in the diesel particulate filters fixated at the exhaust of the engine has been a boon to reduce the particulate matter from entering the atmosphere. Here we have attempted to synthesize the smooth powder of supported and macro-porous perovskite LaFeO3 and its doped variant with 5, 10, 20, and 30% copper on B site. Subsequent catalysts, termed as LFO and LFCO- (5, 10, 20, 30) with formula LaFe1 xCuxO3, were investigated as catalysts for soot oxidation reaction. The structural and physical and chemical attributes of LaFe1-xCuxO3 and LaFeO3 are characterized by XRD patterns, FESEM, BET, particle size analysis measurements. Undoped LaFeO3 with desired textural structures were successfully prepared, employing the citric-acid auto combustion method, and the porous sample exhibits the best activity towards redox reactions, pointing out the enriched activity at redox sites of fabrication of porous perovskite for the responses. By correlating with the catalytic activities and the physical and chemical properties, of both doped and undoped samples, it is inferred that the best activity obtained from the porous LaFe0.9Cu0.10O3 is attributed to its extensive surface area corresponding to least particle size, precious active lattice oxygen, high oxygen storage capacity and vigorous surface activity.

**Keywords:** heterogeneous catalysis, green chemistry, perovskite-type oxides, soot oxidation, sustainability, green and clean synthesis, global warming, greenhouse effect

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