壳-芯结构Gd^(3+)掺杂BaTiO_3/网状PPy吸波材料的性能研究

Absorbing properties of core-shell structure Gd^(3+)-doped BaTiO_3/net structure polypyrole

采用溶胶-凝胶法(sol-gel)制备了Gd3+掺杂钛酸钡纳米粉体,借助XRD、SEM及矢量网络分析仪等分析测试手段对试样晶相、颗粒粒径、表面形貌及吸波特性进行了研究。结果表明:煅烧温度为1 150℃可获得Gd3+掺杂钛酸钡,是顺电相与铁电相的混合相,Gd3+掺杂钛酸钡可产生间隙杂质能级及电偶极子畴壁共振和弛豫共振的改变,影响吸收特性;网状结构的PPy微观具有更大的离域空间,利于形成导电链和局部导电网络,提高导电率,促进电磁波损耗;Gd3+掺杂BaTO3/PPy复合材料,在5.25 GHz左右有最大回损-32 dB,小于-5 dB的频宽达到1.70 GHz。

Nano-particles of Gd^3＋ doped BaTiO3 were prepared by sol-gel method. The microstructure, and absorption properties of the materials were characterized by using X-ray diffraction （XRD）, Scanning Electron Microscope （SEM） and vector network analyzer. The results show that the optimum calcining temperature of Gd^3＋ doped BaTiO3 is 1150 ℃. A mixed phase composed of paraelectric phase and ferroelectric phase can be obtained, and the absorption characteristics can be affected by generating transformation of interstitial impurity level, electric dipole domain wall resonance as well as relaxation resonance. Net structure polypyrole＇ s tremendous delocalization space is conducive to the formation of the conductive chain and the local electric network, and improvement of the conductivity and promotion of the electromagnetic wave loss. The Gd^3＋ doped BaTiO3/PPy composites＇s maximum return loss is -32 dB at 5.25 GHz, and the frequency width is less than -5 dB up to 1.70 GHz.