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The ionic conduction mechanism in M2+-doped (M: Mg, Ca, Zn, and Sr) lanthanum oxybromide (LaOBr) was investigated theoretically and experimentally. Formation energy calculations of point defects revealed that Br− ion vacancies and substitutional M2+ ions were the major point defects in M2+-doped LaOBr, while Br− ion vacancies and antisite O2− ions at Br sites were the major defect types in pure LaOBr. In the relaxed point defect models, doped Mg2+ and Zn2+ ions were displaced from the initial positions of the La3+ ions, and this was experimentally supported by crystal structural analysis. These significant atomic shifts were probably due to the strong interactions between Br− and the dopant ions. First-principles calculations and experimental analyses using X-ray photoelectron spectroscopy and X-ray absorption fine-structure spectroscopy also suggested the existence of strong interactions. The migration energy of Br− ions was calculated to be 0.53 eV, while the migration energy of O2− ions was 0.92 eV, implying that Br− ion migration via a vacancy system was more probable than O2− ion migration. The calculated association energies between MLa and VBr were 0.4–0.6 eV, suggesting that the association needed to be disrupted for Br− ion conduction. The sum of the association and migration energies was comparable to the experimental association energies of M2+-doped LaOBr. [ABSTRACT FROM AUTHOR]

Pt/La1−xBixOF/SBA-16 (SBA-16: Santa Barbara Amorphous no. 16) catalysts were prepared to produce dihydroxyacetone (DHA) from glycerol under moderate conditions. By using 7 wt% Pt/16 wt% La0.95Bi0.05OF/SBA-16, the DHA yield reached up to 78.4% (glycerol conversion: 100%) after reacting for 6 h at 30 °C in an atmospheric open-air system. [ABSTRACT FROM AUTHOR]

Novel ZrSn1−xCoxO4−δ catalysts for the direct decomposition of nitrous oxide (N2O) were synthesized using a co‐precipitation method. Metastable ZrSnO4 with an α‐PbO2‐type structure was used as the mother solid because of its interstitial open spaces derived from its lattice distortion that may be effective for N2O adsorption. The doping of Co2+/3+ into the ZrSnO4 lattice improved the N2O decomposition activity, likely owing to the enhancement of the redox properties and the increase in the number of oxygen vacancies. Among the prepared catalysts, Zr1.17Sn0.73Co0.10O4−δ exhibited the highest activity decomposing N2O completely decomposed at 550°C. In addition, the Zr1.17Sn0.73Co0.10O4−δ catalyst showed high durability in the presence of CO2, O2, and H2O vapor. [ABSTRACT FROM AUTHOR]