Electrostatic capacitors based on dielectrics with high energy density and efficiency are desired for modern electrical systems owing to their intrinsic fast charging-discharging speed and excellent reliability.The lo...Electrostatic capacitors based on dielectrics with high energy density and efficiency are desired for modern electrical systems owing to their intrinsic fast charging-discharging speed and excellent reliability.The longstanding bottleneck is their relatively small energy density.Herein,we report enhanced energy density and efficiency in the Aurivillius Pb_(2)Bi_(4)Ti_(5)O_(18)films by controlling the post-annealing atmosphere.The results demonstrate that the fabrication atmosphere has significant effects on the film texture and defects.As the increase of the oxygen pressure of annealing atmosphere,the Pb_(2)Bi_(4)Ti_(5)O_(18)films show a preferred growth orientation of(00l)and fewer defects,which leads to a higher polarization and breakdown field for the film annealed in air atmosphere and thus help to achieve an ultrahigh energy density of59.4 J·cm^(-3)and an improved efficiency of 81.2%.Moreover,the film also exhibits excellent cycling reliability and good thermal stability.The Pb_(2)Bi_(4)Ti_(5)O_(18)films show a significant potential application for dielectric capacitors.展开更多
基金financially supported by the National Key Research Program of China (No.2021YFB3800601)the Basic Science Center Project of the National Natural Science Foundation of China (NSFC,No.51788104)。
文摘Electrostatic capacitors based on dielectrics with high energy density and efficiency are desired for modern electrical systems owing to their intrinsic fast charging-discharging speed and excellent reliability.The longstanding bottleneck is their relatively small energy density.Herein,we report enhanced energy density and efficiency in the Aurivillius Pb_(2)Bi_(4)Ti_(5)O_(18)films by controlling the post-annealing atmosphere.The results demonstrate that the fabrication atmosphere has significant effects on the film texture and defects.As the increase of the oxygen pressure of annealing atmosphere,the Pb_(2)Bi_(4)Ti_(5)O_(18)films show a preferred growth orientation of(00l)and fewer defects,which leads to a higher polarization and breakdown field for the film annealed in air atmosphere and thus help to achieve an ultrahigh energy density of59.4 J·cm^(-3)and an improved efficiency of 81.2%.Moreover,the film also exhibits excellent cycling reliability and good thermal stability.The Pb_(2)Bi_(4)Ti_(5)O_(18)films show a significant potential application for dielectric capacitors.
