Polarization properties of Na1/2Bi1/2TiO3 system: First-principles calculation and experiment

The polarization properties of Na1/2Bi1/2TiO3 (NBT) lead-free piezoceramics system with the perovskite ABO3 structure are studied by a first-principles-derived approach. The results show that spontaneous polarization exists in the NBT system. The ferroelectric properties are enhanced because of the displacement of the B-site cations. The complex substitution of Ba2+, Sr2+ and Mn4+ cations can reduce the coercive field, and increase the strength of the spontaneous polarization, thus improving the ferroelectric properties. The measured P-E hysteresis loops are in good agreement with results of calculations.