Fig. 1. X-ray diffraction patterns of BFM_0.02–xT_0.02+x-BT ceramics with different x content (0 ≤ x ≤ 0.02) in a selected 2θ range of 20°—70° (a), 38°—40° and 43.5°—46.5° (b). BFM_0.02–xT_0.02+x-BT (0 ≤ x ≤ 0.02)基陶瓷的XRD图谱　(a) 20°—70°; (b) 38°—40°, 43.5°—46.5°

Fig. 2. SEM images of the fracture surface for BFM_0.02–xT_0.02+x-BT ceramics with different x content (0 ≤ x ≤ 0.02). BFM_0.02–xT_0.02+x-BT陶瓷样品的SEM形貌图

Fig. 3. Ferroelectric hysteresis loops (a), the variation of polarization (P_r) and electric field (E_C) (b), leakage current density (I)-electric field (E) (c), as well as the piezoelectric coefficient d₃₃, planar mode eletromechanical coupling coefficient k_p (d) as a function of x for BFM_0.02–xT_0.02+x-BT (0 ≤ x ≤ 0.02). BFM_0.02–xT_0.02+x-BT陶瓷样品的(a)电滞回线, (b)剩余极化P_r和矫顽场E_C随含量x的变化, (c)漏电流I-E曲线, 以及(d)压电性能d₃₃和k_p随含量x的变化

Fig. 4. UV-vis-NIR absorption spectra of the BFM_0.02–xT_0.02+x-BT ceramics with different x content (0 ≤ x ≤ 0.02). BFM_0.02–xT_0.02+x-BT铁电陶瓷的光吸收谱图

Fig. 5. Plots of (αhν)^1/2 versus hν for the BFM_0.02–xT_0.02+x-BT ceramics with different x content: (a) x= 0; (b) x = 0.005; (c) x = 0.01; (d) x = 0.02. BFM_0.02–xT_0.02+x-BT铁电陶瓷的(αhν)^1/2-(hν)曲线　(a) x = 0; (b) x = 0.005; (c) x = 0.01; (d) x = 0.02

Fig. 6. J-t characteristics of BFMT-BT ceramics, which are polarized at different voltage: (I) V = 0 kV; (II) V = 1 kV; (III) V = 2 kV; (IV) V = 3 kV. BFMT-BT铁电陶瓷的光电流密度-时间(J-t)曲线图, 其中(I)区为未极化; (II)区为1 kV下极化; (III)区为2 kV下极化; (IV)区为3 kV下极化

Fig. 7. J-V characteristics of BFM_0.02–xT_0.02+x-BT ceramics with different x content: (a) x = 0; (b) x = 0.005; (c) x = 0.01; (d) x = 0.02 BFM_0.02–xT_0.02+x-BT铁电陶瓷的光电流密度-电压(J-V)曲线图　(a) x = 0; (b) x = 0.005; (c) x = 0.01; (d) x = 0.02

Fig. 8. Schematic diagram of photovoltaic effect for BFM_0.02–xT_0.02+x-BT ceramics, non-polarization and dark condition (a), non-polarization and light condition (b), polarization and dark condition (c), as well as polarization and light condition (d), respectively. BFM_0.02–xT_0.02+x-BT铁电陶瓷光伏效应原理图　(a)未极化、无光条件; (b)未极化、有光条件; (c)极化、无光条件; (d)极化、光照条件