TY - JOUR AU - Boychuk, V. M. AU - Zapukhlyak, R.I. AU - Abaszade, R.G. AU - Kotsyubynsky, V.O. AU - Hodlevsky, M.A. AU - Rachiy, B.I. AU - Turovska, L.V. AU - Dmytriv, A.M. AU - Fedorchenko, S.V. PY - 2022/12/24 Y2 - 2024/03/28 TI - Solution combustion synthesized NiFe2O4 / reduced graphene oxide composite nanomaterials: morphology and electrical conductivity: Array JF - Physics and Chemistry of Solid State JA - Phys. Chem. Sol. State VL - 23 IS - 4 SE - Scientific articles (Physics) DO - 10.15330/pcss.23.4.815-824 UR - https://scijournals.pnu.edu.ua/index.php/pcss/article/view/6407 SP - 815-824 AB - <p>Ultrafine NiFe<sub>2</sub>O<sub>4</sub> (T0) and NiFe<sub>2</sub>O<sub>4</sub>&nbsp;/&nbsp;rGO composites have been synthesized by solution combustion method. The presence of rGO in the composite (33 wt.% (T1) or 66 wt.% (T2)) causes a decrease in the average particle size of the oxide phase from 16 to 10-11 nm with their transition to superparamagnetic with a decrease in the mixed spinel inversion degree. The S<sub>BET</sub> values for T1 and T2 are 180 and 315 m<sup>2</sup>/g, respectively, decreasing to 78 and 169&nbsp;m<sup>2</sup>/g after annealing in the temperature range of 200-800°C. Both micro- and small mesopores (size of 2.0-4.5 nm) have been observed for samples T2, while samples T0 and T1 are mainly mesopores. The small polaron mechanism of electrical conductivity is observed for pure spinel, when the electron hopping charge transport prevails for NiFe<sub>2</sub>O<sub>4</sub>&nbsp;/ rGO composites. It can be assumed that the GO com­po­nent lowers the combustion reaction temperature and prevents particle agglomeration.</p> ER -