Gwóźdź Paulina, Łącz Agnieszka, Górecka Sylwia, Pacultová Kateřina, Górecki Kamil, Obalová Lucie, Drożdż Ewa
Department of Inorganic Chemistry, Faculty of Materials Science and Ceramics, AGH University of Krakow, al. A. Mickiewicza 30, 30-059 Krakow, Poland.
Institute of Environmental Technology, Centre for Energy and Environmental Technologies, VSB-Technical University of Ostrava, 17. Listopadu 2172/15, 708 00 Ostrava-Porub, Czech Republic.
Molecules. 2024 Nov 27;29(23):5603. doi: 10.3390/molecules29235603.
Perovskite materials in the CaTiO-SrTiO system doped with different amounts of iron (1, 2 and 5 mol.%) and various Ca/Sr ratios were prepared by the modified citrate method. Additionally, the materials with 0.05 deficiency in strontium/calcium sublattice and 5 mol.% of Fe were also synthesised. The materials were subjected to structural (XRD, XANES) and microstructural (SEM) characterisation, as well as the analysis of susceptibility to reduction/oxidation processes. The structural analysis indicates a lack of iron-containing phases; thus, an incorporation of Fe into the perovskite structure was postulated. Additionally, the oxidation state of iron in the perovskite structure changes with the dopant amount. The temperature-programmed reduction measurements showed partial reversibility of the reduction processes. For the materials with the highest iron amount, the catalytic tests in NH-SCO and NH-SCR reactions were carried out. The materials showed high catalytic activity and high selectivity to N in the NH-SCR process; however, they were inactive in NH-SCO.
采用改进的柠檬酸盐法制备了CaTiO-SrTiO体系中掺杂不同铁含量（1%、2%和5%摩尔）以及不同Ca/Sr比的钙钛矿材料。此外，还合成了锶/钙亚晶格中存在0.05缺陷且铁含量为5%摩尔的材料。对这些材料进行了结构表征（XRD、XANES）和微观结构表征（SEM），以及对还原/氧化过程的敏感性分析。结构分析表明不存在含铁相；因此，推测铁已掺入钙钛矿结构中。此外，钙钛矿结构中铁的氧化态随掺杂量而变化。程序升温还原测量表明还原过程具有部分可逆性。对于铁含量最高的材料，进行了NH-SCO和NH-SCR反应的催化测试。这些材料在NH-SCR过程中表现出高催化活性和对N的高选择性；然而，它们在NH-SCO中无活性。
