Short-range nanoregions and nanosized defects in LiFeO2 compound deduced from Mössbauer spectroscopy and Rietveld analysis

• Published in: Journal of materials research 2024-06, Vol.39 (11), p.1686-1700
• Main Authors: Panagopoulos, V., Devlin, E., Sanakis, Y., Psycharis, V., Pissas, M.
• Format: Article
• Language: English
• Subjects: Applied and Technical Physics; Biomaterials; Chemistry and Materials Science; Inorganic Chemistry; Materials Engineering; Materials Science; Nanotechnology
• ISSN: 0884-2914; 2044-5326
• DOI: 10.1557/s43578-024-01338-0

We examined the crystal and magnetic properties of the polymorphic LiFeO 2 compound using Mössbauer spectra (MS), X-ray diffraction data (XRD), and magnetic measurements. X-ray diffraction analysis of α -LiFeO 2 and β ′ -LiFeO 2 phases reveals that short-range ordering observed in the α -LiFeO 2 phase is potentially linked to the β ′ -LiFeO 2 phase nanoregions. Low-temperature MS of the α -LiFeO 2 phase reveal a complicated disordered magnetic state below 90 K. Rietveld analysis of the XRD data of the γ -LiFeO 2 phase reveals a defect microstructure. These defects produce a complicated distribution of the hyperfine magnetic field estimated from MS. While it is not possible to produce the β ′ -LiFeO 2 phase in pure form, extended annealing of the α -LiFeO 2 phase at 400 ∘ C yields a nanocomposite material comprising nanoregions of both β ′ -LiFeO 2 and γ -LiFeO 2 phases. Graphical abstract