fig5

Figure 5. Polarization-electric field hysteresis loops (P-E) of (A) 4-SNO and (B) 5-SNGO measured at 150 °C, 10 Hz frequency, under different electric fields. Polarization-electric field (P-E) hysteresis loops and charging current density-electric field (I-E) curves for (C) 4-SNO and (D) 5-SGNO samples at 150 °C, 10 Hz frequency.