Observation of enhanced multiferroic, magnetoelectric and photocatalytic properties in Sm-Co codoped BiFeO3 nanoparticles

• Published in: Journal of alloys and compounds 2017-11, Vol.723, p.983-994
• Main Authors: Arya, Ghanshyam, Yogiraj, Jyoti, Negi, Nainjeet Singh, Shah, Jyoti, Kotnala, Ravinder Kumar
• Format: Article
• Language: English
• Subjects: Bismuth ferrite; Coupling coefficients; Diffraction patterns; Ferroelectric materials; Ferroelectrics; Lattice vacancies; Leakage current; Light irradiation; Magnetic properties; Magnetic saturation; Methylene blue; Multiferroic materials; Nanoparticles; Photocatalysis; Photocatalytic properties; Samarium; Sol-gel processes; Structural analysis; Studies; Tartaric acid; Transition temperature; UV-Vis study; X ray photoelectron spectroscopy
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2017.06.325

Single phase multiferroics BiFeO3 (BFO), Bi0.99Sm0.01FeO3 (Sm1) and Bi0.99 Sm0.01Fe0.99Co0.01 O3 (Sm1Co1) were successively synthesized by tartaric acid assisted sol-gel method. The X-ray diffraction patterns analyzed through Rietveld refinement method confirmed substitution driven structural distortion, which was further supported by William- Hall plot. The morphological analysis of BFO and Sm1Co1 could be effectively controlled to form nanoparticles, due to the smaller ionic radii of the dopants cations. The co-doping of Sm and Co in BFO lattice significantly enhanced the magnetic properties, with the saturation magnetization being 8.4 emu/g, which is about 20 times larger than that of pure BFO (0.40 emu/g). The decrease of Neel transition temperature and irreversible behavior of FC/ZFC curves also support improved magnetic properties. With the codoping of Sm-Co, the band gap was decreased, while interestingly, the leakage current density was significantly reduced to about 10−7 A cm−2. A reduction of oxygen vacancies was confirmed by XPS analysis in the case of Sm1Co1 sample. The codoping leads to improved ferroelectric properties and significant enhancement of magnetoelectric coupling coefficient (9mV/cmOe). The photocalalytic activity of Sm1Co1 enhanced significantly and about 92% degradation of methylene blue dye was achieved using this catalyst under visible light irradiation. •Change of Structural parameters due to Sm-Co codoping.•Enhanced magnetic properties and decrease of TN with codoping.•Simultaneous decrease of band gap and leakage current density.•Increased Ferroelectric and Magnetoelectric properties at room temperature.•Large photocatalytic action of codoped sample.