Synthesis, thermal and magnetic properties of nanoceramics with a multilayer Aurivillius phase type

•Synthesis conditions of seven- and the eight-layer BFTO nanocrystals.•Structure and morphology of Bi8Fe4Ti3O24 and Bi9Fe5Ti3O27 nanocrystals.•Thermal behavior of multilayer BFTO nanocrystals.•Bi9Fe5Ti3O27 is a promising magnetically ordered nanomaterial at room temperature. We report the co-precipitation synthesis and properties of nanomaterials with multilayerAurivillius phase structures Bim+1Fem-3Ti3O3m+3 (BFTO). This paper discusses the thermal behavior of materials based on seven-layerand eight-layercompounds and presents their magnetic characteristics. The structure and morphology were characterized using PXRD, helium pycnometry, and SEM/EDX. Thermal analyses were conducted using DSC/TG. The sintering behavior was investigated through dilatometry. Mössbauer spectroscopy revealed that varying the synthesis conditions allows control over the iron distribution within the Aurivillius phase structure. Spin-phonon coupling effects were examined using Raman spectroscopy. The magnetic characteristics were assessed using vibrating-sample magnetometry. The magnetic propertieswere analyzed by measuring the temperature dependence of magnetization and magnetic hysteresis loops. The magnetic experiments demonstrated that the composition has a more significant impact on the BFTO magnetic responsethan the size effect. The results of this study suggest that the obtained materials have promising functional applications.