Mn掺杂BST陶瓷的本征热释电性能研究

Study on intrinsic pyroelectric property of Mn doped BST ceramics

采用柠檬酸溶胶-凝胶法制备了不同锰掺杂含量的BST陶瓷。研究表明,利用柠檬酸溶胶-凝胶法制备BST陶瓷粉末可以降低BST陶瓷的烧结温度至1250℃,Mn掺杂能明显降低BST陶瓷的铁电性,适量掺杂Mn可以获得具有介电常数适中、介电损耗较小,且室温下具有良好热释电性和探测率优值的BST陶瓷。1%Mn掺杂的BST陶瓷在室温下本征热释电系数γint=610nC/(cm2.K),低频下的探测率优值Fd=88.4×10-6Pa-1/2,可以满足制作热释电探测器的要求。

Mn-doped BST ceramics were prepared by citric acid sol-gel method.Using this method,the sintering temperature of BST-based ceramics could be decrease to 1250℃.The obvious degradation of ferroelectric property of BST-based ceramics was found as Mn bringing in however,with proper content of Mn doping,favor dielectric constant,low dielectric loss,favor pyroelectric property and figure of merit of BST-based ceramics were obtained at room temperature.The intrinsic pyroelectric coefficient γint of 1% Mn-doped BST ceramics reaches 610nC/（cm^2·K）,and the figure of merit Fd of 1% Mn-doped BST ceramics measured at low frequency was 88.4×10^-6Pa-1/2,which can completely meet the need of pyroelectric detectors.In addition,the mechanism of domain switching was discussed during the study.