Two-step enhancement of dielectric property in BiFeO3 by barium doping and irradiation

Abstract Bismuth Ferrite (BiFeO 3 ) is a multiferroic material with high dielectric properties which can be improved by various doping such as lanthanum, and yttrium. In this research, Bi 1-x Ba x FeO 3 ceramics (x = 0 and 0.05) were prepared using simple co-precipitation method with calcining temperature at 600 °C. Here, we report the two steps of capacitance enhancement by doping and violet-light irradiation. Firstly, the dielectric constant of BiFeO 3 is observed to increase approximately 60% (from 230 pF to 360 pF at 10 kHz) by doping with barium (x= 0.05); one main cause of this increase is attributed to the larger grain size. Moreover, the capacitance in this Ba-doped sample can be enhanced by approximately 9% at 1 kHz under violet light exposure (comparing to 2% increase in pure BiFeO 3 ). This indicates that Ba doping can help improving the dielectric property of BiFeO 3 not only in the conventional way but at the same time in another property, such as optoelectronic aspect presented in this work.