硝酸锰对PMN-PZT热释电陶瓷性能的影响

Effect of Manganese Nitrate Doping on the Properties of PMN-PZT Pyroelectric Ceramics

研究了硝酸锰溶液掺杂对富锆铌镁酸铅-锆钛酸铅(PMN-PZT)热释电陶瓷材料的相组成、微观结构、介电性能、热释电性能等方面的影响,并对实验结果作出物理机理的解释。实验结果表明,以液态硝酸锰的形式进行锰掺杂使锰的加入更容易,有效改善了固态锰掺杂时析出损失和混合不均等问题;适量的硝酸锰溶液掺杂有助于陶瓷晶粒的生长,能有效地降低PMN-PZT陶瓷材料的相对介电常数(rε)和介电损耗(tanδ),并增加其热释电系数(p);在x(Mn)=3.0%时,制备出综合热释电性能良好的PMN-PZT热释电陶瓷,即室温时rε=197,tanδ=0.15%,p=3.5×10-8C/cm2℃,探测优值FD=8.7×10-5Pa-1/2,低温铁电相-高温铁电相(FRL-FRH)相变温度时rε=300,tanδ=0.45%,pmax=35×10-8C/cm2℃,FD=40.5×10-5Pa-1/2,符合制作热释电红外探测器的要求。

The effect of manganese nitrate solution doping on the phase composition, microcosmic configuration, dielectric properties and pyroelectric properties of Zr-rich PMN-PZT ceramics was investigated in details, and the physical mechanism aiming at the results of the experiments was explained. The results showed that manganese doping in form of manganese nitrate solution made it more easily to add manganese into ceramics and solved the problem of manganese precipitation and non-uniform mixing when manganese was doped in form of solid state. The roper amount of manganese nitrate solution doping not only contributed to the growth of ceramic grain, but also reduced dielectric constant and dielectric lossed and increased pyroelectric coefficient of PMN-PZT ceramics effectively;When the amount of manganese nitrate solution doping was 3.0 %, we developed the PMN-PZT ceramics with good inte- grated properties：in room temperature,εr=197 ,tan δ=0. 15% ,p=3.5×10^-8C/cm^2 ℃ and FD =8. 7×10^-5 Pa^-1/2 ; during the FRL-FRH transition,εr = 300, tan δ= 0.45 % , Pmax = 35 ×10^-8 C/cm^2 ℃ and FD = 40.5 ×10^-5 Pa^-1/2. These parameters could well met the demand for making pyroelectric infrared detection.