## 3 Results and Discussion
### Antiferroelectricity of La\({}_{0.75}\)Ba\({}_{0.25}\)Fe\({}_{12}\)O\({}_{19}\) Ceramics
The inset is the measured double electrical polarization loop for a different sample, which is also the data source for the energy storage density map. Thus, it can be shown that the AFE feature of La\({}_{0.75}\)Ba\({}_{0.25}\)Fe\({}_{12}\)O\({}_{19}\) is repeatable and reliable. Figure 6: Recoverable energy density of La\({}_{0.75}\)Ba\({}_{0.25}\)Fe\({}_{12}\)O\({}_{19}\) ceramics under different electric fields; the inset shows one more double \(P\)–\(E\) hysteresis loop obtained from a different La\({}_{0.75}\)Ba\({}_{0.25}\)Fe\({}_{12}\)O\({}_{19}\) ceramic specimen. Dielectric Relaxation Behavior of La\({}_{0.75}\)Ba\({}_{0.25}\)Fe\({}_{12}\)O\({}_{19}\) Ceramics  
Figure 7 depicts the temperature-dependent dielectric loss spectrum of La\({}_{0.75}\)Ba\({}_{0.25}\)Fe\({}_{12}\)O\({}_{19}\) ceramics within a wide temperature range from \(-200\)\({}^{\circ}\)C to \(400\)\({}^{\circ}\)C. The frequency spans from 50 kHz to 900 kHz in the low temperature region while it changes from 50 kHz to 200 kHz in the high temperature region. It can be seen from Figure 7 that there appear dielectric anomalous peaks in both the low temperature and high temperature regions, suggesting that La\({}_{0.75}\)Ba\({}_{0.25}\)Fe\({}_{12}\)O\({}_{19}\) ceramic undergoes two phase transitions in both the low and high temperature regions. For the dielectric anomaly peaks at low temperatures, it can be clearly seen that the dielectric anomaly peak shifted to the higher temperature side with increasing frequency, showing a dielectric relaxation behavior. These anomalous peaks were corresponding to the phase transition from ferroelectric (FE) to antiferroelectric (AFE). In this FE-AFE phase transition, when the frequency lifted, the switch duration of the electric field was shortened, and the relaxation time corresponding to it should have also been reduced accordingly. Therefore, the temperature region of relaxation polarization appeared, and the temperature of the dielectric loss peak also increased accordingly. Therefore, the dielectric relaxation behavior in the low temperature part was consistent with the FE-AFE phase transition process. On the other hand, the dielectric anomaly peak in the high temperature region was located within the range of 200-250 \({}^{\circ}\)C, above which the AFE phase changed to the paraelectric phase (PE). La\({}_{0.75}\)Ba\({}_{0.25}\)Fe\({}_{12}\)O\({}_{19}\) behaved as an antiferroelectric, while BaFe\({}_{12}\)O\({}_{19}\) behaved ferroelectric at room temperature (RT). The FE-AFE transition temperature and AFE-PE transition temperature of La\({}_{0.75}\)Ba\({}_{0.25}\)Fe\({}_{12}\)O\({}_{19}\) were shifted to lower temperatures by about 400 \({}^{\circ}\)C and 200 \({}^{\circ}\)C, respectively, compared with the FE-AFE and AFE-PE transition temperatures of BaFe\({}_{12}\)O\({}_{19}\) in previous studies [28]. Thus, it can be seen that the doping of lanthanum has an important effect on the FE-AFE and AFE-PE transitions of BaFe\({}_{12}\)O\({}_{19}\), as the doping could switch it from FE to AFE at RT. Figure 7: Temperature-dependent dielectric loss spectrum of La\({}_{0.75}\)Ba\({}_{0.25}\)Fe\({}_{12}\)O\({}_{19}\) ceramics in the range of \(-190\)\({}^{\circ}\)C to \(400\)\({}^{\circ}\)C (frequency changes from 50 kHz to 900 kHz in the low temperature region, while it varies from 50 kHz to 200 kHz only in the high-temperature region). Magnetic Semiconducting Performance of La\({}_{0.75}\)Ba\({}_{0.25}\)Fe\({}_{12}\)O\({}_{19}\) Ceramics  
UV-vis optical spectrum is usually used to identify the semiconducting performance of solid materials. A Lambda 750 UV-Vis-NIR spectrometer was used to measure the UV-vis-NIR absorption spectrum of the solid La\({}_{0.75}\)Ba\({}_{0.25}\)Fe\({}_{12}\)O\({}_{19}\) ceramics. Figure 8A shows the UV-VIS-NIR absorption spectrum of the La\({}_{0.75}\)Ba\({}_{0.25}\)Fe\({}_{12}\)O\({}_{19}\) ceramic specimen measured by this instrument.