BaTiO_(3)-Bi(Zn_(3/4)W_(1/4))O_(3)无铅弛豫铁电陶瓷的制备及其储能性能的研究

BaTiO_(3)-Bi(Zn_(3/4)W_(1/4))O_(3) Lead-free Relaxor Ferroelectric Ceramics with Improved Energy Storage Properties

采用固相反应法制备了(1-x)BaTiO_(3-x)Bi(Zn_(3/4)W_(1/4))O_(3)[简称(1-x)BT-x BZW]无铅陶瓷电容器。X射线衍射结果表明,所制得的陶瓷均为钙钛矿结构,没有发现第二相的生成。随着BZW的引入使得BaTiO 3陶瓷的晶相结构由四方相转变为伪立方相。采用SEM观察样品的晶粒尺寸和陶瓷表面的致密度,并对晶粒尺寸进行统计分析,陶瓷的平均晶粒尺寸从x=0.05时的2.36μm逐渐增大到x=0.20时的5.93μm。根据P-E曲线(电滞回线)可以观察到,添加适当量的BZW是调节BT弛豫行为的有效方法,能够有效提高陶瓷的储能性能。当掺杂量为x=0.15时,陶瓷具有最佳的储能特性,0.85BT-0.15BZW陶瓷的储能密度W rec为1.14 J/cm^(3),储能效率η可达92.60%,同时具有优异的温度和频率稳定性。因此,(1-x)BT-x BZW陶瓷有望成为制造高稳定性的储能设备的潜在候选材料。

(1-x)BaTiO_(3-x)Bi(Zn_(3/4)W_(1/4))O_(3)[(1-x)BT-x BZW]lead-free ceramics were prepared via solid-state reaction method.X-ray characterization indicated that the as-obtained ceramics show perovskite structure without the formation of a second phase,the tetragonal phase of BaTiO_(3)(BT)transformed into a pseudo-cubic phase via introduction of BZW.The grain size and surface density of the samples were observed by SEM,average grain size of the ceramics gradually increased from~2.36μm at x=0.05 to~5.93μm at x=0.20.It was observed from P-E hysteresis loops that modification with appropriate amount of BZW was an effective approach to modulate relaxation behavior of BT,and its energy-storage performance was promoted significantly.Improved energy-storage performance of W rec~1.14 J cm^(-3) andη~92.60%can be achieved in the 0.85BT-0.15BZW ceramics,accompanied with excellent temperature and frequency stabilities.(1-x)BT-x BZW ceramics are expected to be a potential candidate for energy-storage equipment with high stability.