Multiferroic and optical studies on the effects of Ba2+ ions in BiFeO3 nanoparticles

作者：Kaur Manpreet; Yadav K L; Uniyal Poonam

来源：Journal of Materials Science: Materials in Electronics , 2016, 27(5): 4475-4482.

DOI：10.1007/s10854-016-4320-0

Single phase Ba2+ ions doped BiFeO3 nanoparticles have been successfully synthesized with varied concentration (0.0 a parts per thousand currency sign x a parts per thousand currency sign 0.2) using the auto combustion method. The structural properties of Bi1-xBaxFeO3 (x-0.0, 0.1 and 0.2) nanoparticles reveal the formation of highly crystalline rhombohedrally distorted perovskites without undergoing any structural phase transformation analyzed via Rietveld refinement. The Pauling's equation confirmed that Ba2+ ions doped BiFeO3 ceramics have much more negative enthalpy of formation (Delta H (f) ) than undoped BiFeO3. A reduction of particle size has been observed up to x = 0.1 and then after increases, whereas the band gap shows a reverse trend. Magnetic and ferroelectric transition temperatures are found to be slightly shifted towards the lower temperature up to x = 0.1 and then higher temperature side which could be attributed to the particle size effect. Ba2+ doped BiFeO3 ceramic with concentration x = 0.2 exhibit larger magnetization as compared to others at room temperature, but these magnetization curves were not saturated. Remnant polarization is found to decrease from 7.693 to 5.141 A mu C/cm(2) along with the doping of Ba2+ ions. The on-site d-to-d crystal field excitations of Fe3+ ions associated with (6)A(1g)-T-4(1g) or (6)A(1g)-T-4(2g) electronic energy levels, Fe(1)3d-Fe(2)3d inter-site electron transfer and inter-atomic O 2p-Fe 3d electronic energy levels are observed by the means of absorption spectroscopy.

• 出版日期2016-5