Single-phase Bi (1-x) Ba x FeO 3 (0.00 ⩽ x ⩽ 0.20) thin films are successfully deposited on glass substrates by using a spray pyrolysis method. Rietveld analysis of x-ray diffraction patterns confirms that the films are crystallized in a distorted rhombohedral perovskite structure with an R3c space group. No substantial changes in the structure are observed in the samples within the studied doping concentration. The energy dispersive spectroscopy pattern and morphology of the thin films are examined with field emission scanning electron microscopy. Raman modes confirmed slight structural distortions with the increase in Ba concentration. X-ray photoelectron spectroscopy of the thin films shows the effect of Ba 2+ in the formation of Fe 2+ defects and oxygen vacancies. The room temperature magnetic characterizations of the thin films are measured by using a vibrating sample magnetometer within a range of 10 kOe magnetic field. The values of saturation magnetization and the remnant magnetization are increased with an increase in Ba concentration as compared to the pure bismuth ferrite thin film. The optimum value of field-dependent saturation magnetization (2.4069 emu gm −1 ) and field-dependent remnant magnetization (0.6279 emu gm −1 ) are observed for Ba substituted bismuth ferrite samples with x = 0.10.

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Thin films of Bi(1−x)Sr x FeO3 (X = 0.00, 0.05, 0.10, 0.20, and 0.30) are synthesized on ultra-cleaned glass substrates by simple spray pyrolysis method at 550 °C. The crystal structures of the thin films are investigated by x-ray diffraction (XRD). The Rietveld refinement data for all the thin films are confirmed a single-phase ABO3 type of rhombohedral structure belonging to the R3c space group. The field emission scanning electron microscopy (FESEM) analysis reveals the size of grains from hexagonal to spherical shape with the addition of Sr doping. The vibrational modes are studied by Raman spectroscopy. The x-ray photoelectron spectroscopy (XPS) analysis unravels the influence of Sr2+ in the creation of Fe2+ defects and oxygen vacancies. The room temperature magnetic measurements of the thin films are carried out within a magnetic field range of ±10 kOe. Magnetic hysteresis loop confirms a significant increase in magnetization in Sr modified bismuth ferrite thin films. The composition i.e. X = 0.20 shows maximum enhancement of magnetic properties with saturation and Remanent magnetization values of 5.99 emu g−1 and 1.77 emu g−1, respectively.

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In this work, Bi1−x Ca x FeO3 (for x = 0.00–0.30) single-phase thin films were developed on clean glass substrates via simple spray pyrolysis technique. The microscopic crystal structure and magnetic characteristics of the Ca modified thin films were investigated. X-ray diffraction study confirms the hexagonal structure with the space group R3c for all the prepared thin film samples. The crystallite sizes and lattice strains were computed by using the Williamson–Hall plot. The morphology of the samples was viewed by field emission scanning electron microscopy which shows that the average size of grains systematically decreases with the addition of Ca atom at Bi site. The compositions of samples were confirmed by using energy dispersive spectroscopy. The structural phase transition and the position of different Raman modes were observed by using the Raman spectroscopy technique. The elementary compositions, different oxidation states, and the effect of oxygen vacancies of the elements were observed by x-ray photoelectron spectroscopy. The magnetic field (H) dependence of magnetization (M) (i.e. M–H hysteresis loops) of the pure bismuth ferrite (BFO) and Ca doped BFO thin film samples conducted at room temperature using a vibrating sample magnetometer with an applied magnetic field of ±30 kOe and confirmed that the value of magnetization significantly increases with Ca addition at Bi-site in BFO atom. The maximum value saturation magnetization of 3.8176 emu g−1 and remanent magnetization of 0.1408 emu g−1 obtained for the 25% Ca doped BFO thin films.