Multifunctional KBiFe2O5 thick film: advances in functional properties

• Published in: Journal of materials science. Materials in electronics 2020-07, Vol.31 (13), p.10234-10240
• Main Authors: Jalaja, M. A., Dutta, Soma
• Format: Article
• Language: English
• Subjects: Antiferromagnetism; Characterization and Evaluation of Materials; Chemistry and Materials Science; Crystal structure; Efficiency; Electric fields; Electromagnetic absorption; Energy gap; Ferroelectric materials; Ferroelectricity; Ferromagnetic materials; Hysteresis loops; Investigations; Laboratories; Light; Materials Science; Optical and Electronic Materials; Optical properties; Photoelectric effect; Photoelectric emission; Polarization; Room temperature; Switching
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-020-03569-3

This paper presents the preparation of KBiFe 2 O 5 thick film and its optical (bandgap), ferroelectric, and photovoltaic properties. The XRD of KBiFe 2 O 5 film reveals orthorhombic crystal structure. The polarization study with an electric field (P–E) shows unsaturated and leaky nature of the hysteresis loop. The film shows fatigue-free polarization till 10 7 switching cycles. A weakly ferromagnetic behavior is observed in the KBFO film at room temperature arising from the canting of G-type antiferromagnetic spins. The film shows spin-frozen behavior below 125 K. The bandgap value of KBiFe 2 O 5 film is found to be 1.67 eV, which is appropriate for visible light absorption. The photovoltaic study on KBiFe 2 O 5 film gives V oc = 1.89 V, J sc =  − 3.04 × 10 4 A/cm 2 , and photovoltaic efficiency 0.11%. The photo-ferroelectric coupling in KBiFe 2 O 5 film is established from the directional change in photocurrent with the polarization switching under forward and reverse fields and also from the enhancement of polarization under light illumination.