铈掺杂钛酸钡微粉制备与微波吸收特性研究

Preparation and Microwave Absorption Properties of Ce-doped BaTiO_3

采用溶胶-凝胶法制备了稀土铈掺杂钛酸钡纳米晶粉体,借助XRD、Raman、SEM以及矢量网络分析仪等分析测试手段对样品晶相、晶格常数、粒径、表面形貌及微波吸收特性进行了研究.结果表明:铈掺杂样品均形成四方相钛酸钡微晶,晶粒发育良好.随着铈掺杂量增大,晶粒逐渐细化,晶格常数a变大,晶格常数c减小;与未掺杂钛酸钡相比,在2～18GHz频率范围内,稀土铈掺杂材料(掺杂量0.2%)的反射损耗明显地提高,反射峰发生蓝移,尤其5.8GHz和7GHz处反射损耗分别提高了15dB和30dB,频带拓宽近2倍.由此可见铈掺杂有利于改善钛酸钡材料的微波吸收特性.

Nano-particles of Ce-doped BaTiO3 were prepared by sol-gel method. The structure, micrograph and microwave absorption properties of the materials were characterized by using X-ray diffraction （XRD）, Raman spectroscope, Scanning Electron Microscope （SEM） and vector network analyzer. The BaTiOa powders doped with different Ce contents have the same crystalline tetragonal structure. With the increase of Ce content, the crystal sizes of the BaTiOa powders decrease with lattice constants a enlarges and c decreases. Within the bandwidth of 2-18GHz, the reflection loss of 0.2% Ce-doped BaTiO3 powders is increased and reflection peak has blue shift compared with pure BaTiO3 powders. Reflection losses of 0.2-70 Ce-doped BaTiOa powders are increased by 15dB and 30dB at 5.8OHz and 7GHz, respectively, and the bandwidth is widened two times. The above shows that Ce-doping can greatly improve the microwave absorption properties of the BaTiO3 powders.