Temperature programmed desorption of co from reduced perovskite oxides LnCoO3−x (Ln=La, Sm)

Energetics of lanthanide cobalt perovskites: LnCoO3−δ (Ln = La, Nd, Sm, Gd)

“…The observed trend on energetics of lanthanide cobaltite perovskites in the present work compares well with energies of the reduction reaction; LnCoO 3 / 0.5Ln 2 O 3 + CoO + 1/2O 2 (g), observed by Lago et al 38 and Arakawa et al 39 The reduction reactions were assumed to be thermodynamically controlled. Among the considered series, LaCoO 3 , with highest thermodynamic stability, reduces at the highest temperatures.…”

Integrated Experimental–Theoretical Approach To Determine Reliable Molecular Reaction Mechanisms on Transition-Metal Oxide Surfaces

“…Following the surface construction, CO oxidation was modeled on all three perovskites, LaFeO 3 , LaMnO 3 , and SmCoO 3 , and compared to the CO/CO 2 TPD reported in the literature to demonstrate the reliability of this method. CO oxidation was chosen for perovskite oxides due to the abundance of data on this reaction mechanism that can be found in the literature. − LaFeO 3 has a CO 2 peak at 150 °C . Reduced LaMnO 3 , at 300 °C, showed a CO peak at 102 and 625 °C and fresh LaMnO 3 had a CO 2 peak at 341 °C. , Lastly, SmCoO 3 reduced at 500 °C has been reported to have a CO peak at 575 °C .…”

“…CO oxidation was chosen for perovskite oxides due to the abundance of data on this reaction mechanism that can be found in the literature. − LaFeO 3 has a CO 2 peak at 150 °C . Reduced LaMnO 3 , at 300 °C, showed a CO peak at 102 and 625 °C and fresh LaMnO 3 had a CO 2 peak at 341 °C. , Lastly, SmCoO 3 reduced at 500 °C has been reported to have a CO peak at 575 °C . Since all reduction temperatures were below the threshold for surface reconstruction for each material, a reduced surface can be made and modeled using DFT.…”

“…CO oxidation was chosen for perovskite oxides due to the abundance of data on this reaction mechanism that can be found in literature. [22][23][24][25] LaFeO3 has a CO2 peak at 150 °C. 22 Reduced LaMnO3, at 300 °C, showed a CO peak at 102 and 625 °C and fresh LaMnO3 had a CO2 peak at 341 °C.…”

“…23,24 Lastly, SmCoO3 reduced at 500 °C has been reported to have a CO peak at 575 °C. 25 Since all the reduction temperatures were below the threshold for surface reconstruction for each material, a reduced surface can be made and modeled using DFT. Using the surfaces created with oxygen TPD, a reduced surface can easily be made by removing unfavorable surface oxygen atoms.…”