Perovskites with cotton-like morphology consisting of nanoparticles and nanorods: Their synthesis by the combustion method and their NOx adsorption behavior

The perovskites La0.8A0.2MnO3 (A = Cs) and La0.8A0.2Mn0.8B0.2O3 (A = Cs and B = Ga) have been synthesized by a solution-combustion method using metal nitrates, urea and glucose as the fuel materials. The structures of the synthesized products were studied by XRD, FT-IR, SEM, and BET analyses. The morphology of La0.8Cs0.2MnO3 (LCM) was cotton-like whereas the product of La0.8Cs0.2Mn0.8Ga0.2O3 (LCMG) was comprised of rather voluminous cotton-like morphology coexisting with nanorods. The nanorods are quite long, straight, and round and have a much smoother surface structure. The perovskite products have been tested as catalysts for NO + NO2 (NOx) adsorption. The formation of various species during the adsorption of NOx, issuing from a synthetic, lean-burn exhaust gas upon LCM and LCMG was studied using FT-IR. Rapid adsorption of NOx by the perovskites with cotton-like morphology consisting of nanoparticles and nanorods was highly effective for NOx removal from the gas phase.