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.