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采用静电纺丝法结合溶胶-凝胶技术制备了钙钛矿型La_(0.67)Ba_(0.33)MnO_3微纳米纤维,并利用差示扫描量热-热失重分析(DSC-TGA)、X射线衍射(XRD)、傅里叶变换红外光谱(FTIR)和扫描电子显微镜(SEM)等技术对产物进行了表征,利用IR-2红外发射率测试仪测试了La_(0.67)Ba_(0.33)MnO_3在280~370 K范围内的红外发射率.结果表明,La_(0.67)Ba_(0.33)MnO_3在600℃时已形成钙钛矿结构.随着煅烧温度的升高,La_(0.67)Ba_(0.33)MnO_3的形貌由纤维状向三维网络状转变,并最终失去纤维形态.在280~370 K范围内,La_(0.67)Ba_(0.33)MnO_3微纳米纤维的红外发射率随温度升高而升高,由0.564增加至0.689.利用钙钛矿材料双交换理论解释了这一现象,并进一步探讨了其在红外发射率可变材料中的应用前景.
The perovskite type La 0.67 Ba 0.18 MnO 3 micro / nanofibers were prepared by electrospinning and sol-gel technique. The microstructure and mechanical properties were characterized by differential scanning calorimetry-thermogravimetric analysis (DSC-TGA), X-ray diffraction The products were characterized by XRD, FTIR and SEM. The emission spectra of La_ (0.67) Ba_ (0.33) MnO_3 at 280 ~ 370 K. The results show that the perovskite structure of La 0.67 Ba 0.33 MnO 3 has been formed at 600 ℃ with the increase of calcination temperature and the La 0.67 Ba 0.33 MnO 3 The morphology of the nanowires changes from fibrous to three-dimensional networks and finally loses the fiber morphology.The infrared emissivity of La 0.67 Ba 0.33 MnO 3 micro / nanofibers increases with increasing temperature in the range of 280-370 K, From 0.564 to 0.689. This phenomenon is explained by the double-exchange theory of perovskite materials and its application prospect in the variable material of infrared emissivity is further discussed.