Electrical transport properties of the six-layer hexagonal SrMn1−xVxO3−δ (x = 0.02)

• Published in: Journal of alloys and compounds 2021-12, Vol.886, p.1, Article 161232
• Main Authors: Konstantinova, Ekaterina I., Leonidova, Olga N., Markov, Alexey A., Leonidov, Ilia A.
• Format: Article
• Language: English
• Subjects: Ceramics; Combustion synthesis; Disproportionation; Electrical resistivity; Electron spin; Enthalpy; High temperature; Manganese ions; Manganite; Perovskite; Perovskites; Seebeck effect; Strontium oxides; Transport properties
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2021.161232

•Vanadium stabilizes the six-layer hexagonal structure of SrMnO3−δ.•Electrical conductivity and Seebeck coefficient of 6H-SrMn0.98V0.02O3−δ are studied.•Electron transport is carried out by small polarons.•Disproportionation of Mn3+ ions reduces the concentration of charge carriers. In contrast to 6H-SrMnO3 which is usually synthesized using a high-pressure and high-temperature technique, SrMn1−xVxO3 oxides can be prepared via a solution combustion synthesis route with final annealing in air. Doping of SrMnO3 with vanadium allows the formation of the SrMn1−xVxO3 oxide (x = 0.02) which crystallizes in a six-layer hexagonal structure (space group P63/mmc, Z = 6). The specific electrical conductivity (σ) and Seebeck coefficient (S) are measured in the temperature (Т) range 350–1220 K in air. The metallic-like change in S with T is explained employing the model of the motion of small polarons considering the disproportionation of Mn3+ ions to Mn2+ and Mn4+ and the spin direction of t2g-electrons manganese. The enthalpy of disproportionation reaction (130 meV) in 6H-SrMn0.98V0.02O3–δ is higher than in other perovskite-type manganites.