Enhanced energy storage properties in La(Mg1/2Ti1/2)O-3-modified BiFeO3-BaTiO3 lead-free relaxor ferroelectric ceramics within a wide temperature range

摘要

A new ternary lead-free (0.67-x)BiFeO3-0.33BaTiO(3)-xLa(Mg1/2Ti1/2)O-3 ferroelectric ceramic exhibited an obvious evolution of dielectric relaxation behavior. A significantly enhanced energy-storage property was observed at room temperature, showing a good energy-storage density of 1.66 J/cm(3) at 13kV/mm and a relatively high energy-storage efficiency of 82% at x=0.06. This was basically ascribed to the formation of a slim polarization-electric field hysteresis loop, in which a high saturated polarization P-max and a rather small remnant polarization P-r were simultaneously obtained. Particularly, its energy storage properties were found to depend weakly on frequency (0.2 Hz-100 Hz), and also to exhibit a good stability against temperature (25 degrees C-180 degrees C). The achievement of these characteristics was attributed to both a rapid response of the electric field induced reversible ergodic relaxor to long-range ferroelectric phase transition and a typical diffuse phase transformation process in the dielectric maxima. (C) 2016 Elsevier Ltd. All rights reserved.