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Kojčinović J, Tatar D, Šarić S, Bartus Pravda C, Mavrič A, Arčon I, Jagličić Z, Mellin M, Einert M, Altomare A, Caliandro R, Kukovecz Á, Hofmann JP, Djerdj I. Resolving a structural issue in cerium-nickel-based oxide: a single compound or a two-phase system? Dalton Trans 2024; 53:2082-2097. [PMID: 38180044 DOI: 10.1039/d3dt03280a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2024]
Abstract
CeNiO3 has been reported in the literature in the last few years as a novel LnNiO3 compound with promising applications in different catalytic fields, but its structure has not been correctly reported so far. In this research, CeNiO3 (RB1), CeO2 and NiO have been synthesized in a nanocrystalline form using a modified citrate aqueous sol-gel route. A direct comparison between the equimolar physical mixture (n(CeO2) : n(NiO) = 1 : 1) and compound RB1 was made. Their structural differences were investigated by laboratory powder X-ray diffraction (PXRD), selected area electron diffraction (SAED), transmission electron microscopy (TEM) with an energy-dispersive X-ray spectroscopy (EDS) detector, and Raman spectroscopy. The surface of the compounds was analyzed by X-ray photoelectron spectroscopy (XPS), while the thermal behaviour was explored by thermogravimetric analysis (TGA). Their magnetic properties were also investigated with the aim of exploring the differences between these two compounds. There were clear differences between the physical mixture of CeO2 + NiO and RB1 presented by all of these employed methods. Synchrotron methods, such as atomic pair distribution function analysis (PDF), X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS), were used to explore the structure of RB1 in more detail. Three different models for the structural solution of RB1 were proposed. One structural solution proposes that RB1 is a single-phase pyrochlore compound (Ce2Ni2O7) while the other two solutions suggest that RB1 is a two-phase system of either CeO2 + NiO or Ce1-xNixO2 and NiO.
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Affiliation(s)
- Jelena Kojčinović
- Department of Chemistry, Josip Juraj Strossmayer University of Osijek, Cara Hadrijana 8/A, 31000 Osijek, Croatia.
| | - Dalibor Tatar
- Department of Chemistry, Josip Juraj Strossmayer University of Osijek, Cara Hadrijana 8/A, 31000 Osijek, Croatia.
| | - Stjepan Šarić
- Department of Chemistry, Josip Juraj Strossmayer University of Osijek, Cara Hadrijana 8/A, 31000 Osijek, Croatia.
| | - Cora Bartus Pravda
- Department of Applied and Environmental Chemistry, University of Szeged, 6720 Szeged, Hungary
| | - Andraž Mavrič
- University of Nova Gorica, Vipavska 13, 5000 Nova Gorica, Slovenia
| | - Iztok Arčon
- University of Nova Gorica, Vipavska 13, 5000 Nova Gorica, Slovenia
- Institute Jožef Stefan, Jamova 39, 1000 Ljubljana, Slovenia
| | - Zvonko Jagličić
- Institute of Mathematics, Physics, and Mechanics, University of Ljubljana, Jamova 2, 1000 Ljubljana, Slovenia
- Faculty of Civil & Geodetic Engineering, University of Ljubljana, Jadranska 19, 1000 Ljubljana, Slovenia
| | - Maximilian Mellin
- Surface Science Laboratory, Department of Materials and Earth Sciences, Technical University of Darmstadt, Otto-Berndt-Strasse 3, 64287 Darmstadt, Germany
| | - Marcus Einert
- Surface Science Laboratory, Department of Materials and Earth Sciences, Technical University of Darmstadt, Otto-Berndt-Strasse 3, 64287 Darmstadt, Germany
| | - Angela Altomare
- Institute of Crystallography, CNR, via Amendola 122/o, Bari 70126, Italy
| | - Rocco Caliandro
- Institute of Crystallography, CNR, via Amendola 122/o, Bari 70126, Italy
| | - Ákos Kukovecz
- Department of Applied and Environmental Chemistry, University of Szeged, 6720 Szeged, Hungary
| | - Jan Philipp Hofmann
- Surface Science Laboratory, Department of Materials and Earth Sciences, Technical University of Darmstadt, Otto-Berndt-Strasse 3, 64287 Darmstadt, Germany
| | - Igor Djerdj
- Department of Chemistry, Josip Juraj Strossmayer University of Osijek, Cara Hadrijana 8/A, 31000 Osijek, Croatia.
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