Effects of glass additives on microstructure, dielectric and ferroelectric properties of BaTiO3–BiYbO3 based ceramics

Abstract

(100–x) wt% (0.95BT–0.05BY)–x wt% (0.5MgO–0.5SiO2) (x = 0, 1, 2, 4, 8) ceramics were fabricated by using a solid-state synthesis method. The effects of the MgO–SiO2 doping on the microstructure, the ferroelectric, and the dielectric properties of BT–BY ceramics were investigated in detail. The results show that the relative permittivity initially decreases and then increases again upon the increase in the MgO–SiO2 content. The addition of the MgO–SiO2 glass oxide dopant enhances the frequency and the temperature stability of the relative permittivity of BT–BY ceramics. Moreover, the coercive field and the remnant polarization increase and then decrease with increasing MgO–SiO2 dopant content, while the slim P–E loops are observed when x ≥ 2. The largest values for the remanent polarization (1.2 μC cm−2) and the coercive field (9.18 kV cm−1) are obtained at x = 1. The addition of MgO–SiO2 can induce a small leakage current in the BT–BY ceramic when x ≥ 2. The breakdown strength increases with decreasing grain size when MgO–SiO2 is added moderately. Its value increases from 80 kV cm−1 up to 100 kV cm−1 when x changes from 0 to 8. The energy storage density and efficiency of the (100–x) wt% (0.95BT–0.05BY)–x wt% (0.5MgO–0.5SiO2) ceramics decrease and then increase with increasing x. The maximum values of the electrical energy storage density (0.24 J cm−3) and energy efficiency (85.77%) are obtained when x = 8.