WANG Xinkun, ZHAO Fang, TANG Xiangjun, Duan Rongxia, WANG Jianjiang
(Army Engineering University Shijiazhuang Campus, Shijiazhuang 050003, Heibei, China)

Abstract: SnO₂ hollow nanofibers doped with different concentrations of La³⁺ were prepared by electrospinning combined with heat treatment. The samples were characterized by TGA-DSC, XRD and SEM. The resistivity and infrared emissivity of the products were tested using a ST2258C digital four-probe tester and an IR-2 infrared emissivity tester. Results show that the precursor fiber has a smooth surface with an average diameter of about 200 nm. After calcination of the precursor fiber at 600 °C, La³⁺-doped SnO₂ nanofibers with rutile structure were formed, indicating that the doping of La³⁺ did not change the crystal structure of SnO₂ fiber. The surface of the single fiber is formed by the deposition of La³⁺-doped SnO₂ particles with an average diameter of about 90 nm. The morphology of the fiber is hollow. In addition, the infrared emissivity of the product changes with the doping concentration of La³⁺，which is consistent with the change in resistivity. When the doping ratio of La³⁺ is 0.3mol%, the lowest infrared emissivity is 0.72. This makes La³⁺-doped SnO₂ hollow nanofibers have potential applications in infrared emissivity nanomaterials.
Key words: La³⁺-doping; hollow nanofibers; morphology and structure; infrared emissivity