Structural, morphological and optical properties of barium doped bismuth ferrite thin films deposited by spray pyrolysis

Abstract

In the area of material science and technology, fabrication and characterization of nano-materials play an important role since it leads to the development of devices with interesting performance and potential applications in electronics, magnetics, optics, and photonics. Among the materials perovskite materials are gaining prominence. In this investigation, thin films of bismuth ferrite have been prepared and the impact of co–substitution of barium on their structural, morphological and optical properties have been studied. The spray pyrolysis procedure was used to prepare the thin films of bismuth ferrite with medium thickness by doping barium with concentrations of 1%, 3%, 5% and 10%. Various characterization techniques were employed to study the films. The presence of barium, bismuth and iron in the samples was confirmed by EDAX spectra. X-Ray diffraction studies confirmed the polycrystalline nature of the films having a rhombohedrally distorted pervoskite crystal structure fitting to space group R3c. The Scherrer rule was applied to obtain the crystallite size which was found to be small. Surface morphology studies carried out using field emission scanning electron microscopy revealed that the grain size and roughness of the films are modified with increase in doping concentration. The measurement results of optical absorption showed an increase in optical band gap with doping with barium. The results of structural, morphological and optical parameters with the increasing doping concentration indicate that these films are promising candidate for applications in opto-electronics, photovoltaics and gas sensors.