Rare earth element-doped Bi_0.5Na_0.5TiO₃–BaTiO₃ (BNT–BT–RE) polycrystalline thin films were processed on a platinized substrate by chemical solution deposition. The microstructure, dielectric, and ferroelectric properties were investigated for all prepared films. It was found that the incorporation of rare earth elements into the BNT–BT matrix increases both the dielectric constant and the breakdown strength while maintaining low dielectric losses, leading to an enhancement of the energy storage density to W_rec = 12 and 16 J/cm³ under an effective field of E = 2500 kV/cm, for Nd- and Dy-based films, respectively. The optical properties of films containing the lanthanide element were investigated and the obtained results bear interest for luminescence applications. The simultaneous appearance of ferroelectric and optical properties in the system under investigation is very promising for advanced optoelectronic devices.

Bismuth sodium titanate (BNT) thin films were deposited on Pt/SiN substrates by Sol-Gel spin coating technique and annealed under O₂ atmosphere. The microstructural, structural, and electrical properties of the obtained film were investigated. Electron microscopy scans and atomic force microscopy micrographs were used to analyze the microstructure of the films. Furthermore, energy-dispersive X-ray spectroscopy (EDX) analysis revealed a Na-deficient composition for the obtained film. X-ray diffraction and Raman spectroscopy allowed the identification of a pure perovskite BNT phase. Dielectric, ferroelectric, and leakage current measurements revealed good frequency stability of the dielectric constant and dielectric losses for BNT thin film. The results are discussed in terms of Na deficiency effects on the defect structure of BNT. Further, the film showed attractive electrostatic energy storage properties with energy density that exceeds 1.04 J/cm³ under E = 630 kV/cm.

Bismuth sodium titanate thin films (BNT) were deposited on Pt/SiN substrates by Sol-Gel spin coating technique under O2 atmosphere. Microstructural, structural, and electrical properties of the obtained film were investigated. Scanning electron microscopy and atomic force microscopy micrographs were used to analyze the microstructure of the films. Furthermore, EDX analysis revealed a Na-deficient composition for the obtained film. X-ray diffraction and Raman spectroscopy allowed the identification of a pure perovskite BNT phase. Dielectric, ferroelectric, and leakage current measurements revealed good frequency stability of the dielectric constant and dielectric losses for BNT thin film. The results are discussed in terms of Na-deficiency effects on the defect structure of BNT. Further, the film showed attractive electrostatic energy storage properties with energy density that exceeds 1.04 J/cm3 under E = 630 kV/cm.