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Item Studies on the Solid Oxide Cell Perovskite Electrode Materials for Soot Oxidation Activity(Springer, 2019) Shenoy, C.S.; Patil, S.S.; Govardhan, P.; Shourya, A.; Prasad Dasari, H.P.; Saidutta, M.B.; Harshini, H.Solid oxide cell (SOC) perovskite electrode materials (BSCF (Ba0.5Sr0.5Co0.8Fe0.2O3-?), LSCF (La0.6Sr0.4Co0.2Fe0.8O3-?) and LSCM (La0.75Sr0.25Cr0.5Mn0.5O3-?)) were synthesised using microwave-assisted reverse-strike co-precipitation method and tested for soot oxidation activity. The calcined perovskite materials were characterized using FT-IR, XRD, SEM and BSE, BET and BJH and XPS analysis. The mean activation energy for soot oxidation was calculated from Ozawa plots at various heating rates (5, 10, 15 and 20 K/min) at different levels of soot conversions (T10 to T90) for BSCF, LSCM and LSCF perovskite materials and was around 133 ± 11.5, 138 ± 9.9 and 152 ± 7.2 kJ/mol, respectively. Irrespective of the heating rates, BSCF material showed the lowest T50 temperature than compared to other samples, and it is correlated to the presence of Fe3O4 as a secondary phase. © 2019, Springer Nature Switzerland AG.Item Manganese doped Ceria (Ce1−xMnxO2−δ (x = 0–0.3)) catalysts synthesized by EDTA–Citrate method for soot oxidation activity(Springer Science and Business Media Deutschland GmbH, 2022) Shourya, A.; Prasad Dasari, H.P.Ceria–Manganese oxide catalysts (Ce1−xMnxO2−δ where x = 0, 0.05, 0.1, 0.2, and 0.3, termed CM0, CM5, CM10, CM20, and CM30, respectively) were synthesized by EDTA–Citrate method, calcined at 600 °C/5 h, and checked for soot oxidation activity. The XRD spectra exhibited the cubic fluorite phase formation and complete solubility of Mn in Ceria lattice up to CM30. BET and BJH analysis showed that the surface area and pore volume had an appreciable influence on the soot oxidation activity, as seen in the case of CM5, which had superior BET surface area (50 m2/g) as well as pore volume (0.128 cc/g). The Raman spectra revealed secondary phase formation of Mn3O4 peak in CM20 and CM30. FESEM analysis was carried out for all the CMX samples. TEM images displayed the decrease in the particle size of CM5 with the inclusion of Manganese ions into the Ceria lattice. SAED analysis provided evidence for the polycrystalline nature of CM5 compared to CM0. Soot oxidation activity was carried out in tight contact conditions and an air atmosphere. CM5 with a T50 of 360 °C had the least among the CMX catalysts. Ozawa and KAS methods were used to determine the soot oxidation activation energy. CM5 had the least activation energy with 118 kJ/mol (Ozawa) and 114 kJ/mol (KAS). High specific surface area, pore-volume, relatively higher exposed (220) and (200) planes, the lower activation energy for soot oxidation activity, high synergy, and robust interactions between Ceria and Manganese oxides were pivotal in the decrease in soot combustion temperature of the CM5 catalyst. Graphical abstract: [Figure not available: see fulltext.] © 2022, Institute of Chemistry, Slovak Academy of Sciences.Item Formation of nano-rod structures in manganese-rich ceria–manganese mixed oxides and their soot oxidation activity(Elsevier B.V., 2023) Shourya, A.; Prasad Dasari, H.P.EDTA-citrate synthesized manganese-rich ceria–manganese oxide catalysts (Ce1−xMnxO2−δ; where x = 1 to 0.6, termed CM100, CM90, CM80, CM70, CM60, CM50 and CM40 respectively) were obtained after calcination at 600 °C/5 h, characterized and tested for soot oxidation activity. Mn3O4 and Mn2O3 phases were observed in the XRD spectra; with the increase in the ceria concentration, cubic fluorite phase formation was observed from CM80 to CM40. BET and BJH analyses revealed that the pore diameter and volume had a meaningful impact on the soot oxidation activity, as seen for CM80 which had a BET surface area of 31 m2/g, pore diameter of 21.119 nm, and a pore volume of 0.1637 cc/g. The formation of the Mn3O4 peak in all the synthesized catalysts and ceria's cubic fluorite F2g peak (452 cm −1) were observed from CM80 to CM40 from Raman spectral analysis. FESEM analysis of all the CMX samples revealed an intriguing aspect, the appearance of nano-rods. These nano-rods were observed in the HRTEM imaging as well. The high-resolution imaging and SAED analysis proved that the nano-rod structures were primarily due to the α-MnO 2 phase. The mixture of agglomerates and nano-rods profoundly affected the soot oxidation activity of the synthesized samples. CM70 had a minimum T50 of 389 °C among the CMX catalysts. The activation energy was reckoned with the Ozawa and KAS methods. CM50, with 131 kJ/mol for Ozawa and 127 kJ/mol for the KAS method, had the lowest values among the chosen catalysts. Synergistic interactions between ceria and the manganese oxides, considerable specific surface area, pore diameter, pore volume, substantially higher exposed (220) and (200) planes and the formation of the nano-rods helped to lower the activation energy for soot oxidation activity and consequently a reduction in the soot oxidation temperature of CM50 to CM70. The concentration of the nano-rods rendered a considerable role in reducing the T50 temperatures of the CMX catalysts. © 2023 Elsevier B.V.