Morphology variation of nanofibers from controlling matter diffusion in calcination processes / Yunshi Liu, Ping Yang, Jia Li, Katarzyna Matras-Postolek, Yunlong Yue // Materials Chemistry and Physics ... więcej

Morphology variation of nanofibers from controlling matter diffusion in calcination processes / Yunshi Liu, Ping Yang, Jia Li, Katarzyna Matras-Postolek, Yunlong Yue // Materials Chemistry and Physics [Dokument elektroniczny]. – 2017, Vol. 186, s. 312-316 : rys., tab., wykr. – Tryb dostępu: http://www.sciencedirect.com/science/article/pii/S0254058416308124. – Bibliogr. 29 poz., Abstr. – doi: 10.1016/j.matchemphys.2016.11.001. – ISSN 0254-0584

One dimensional metal oxide materials with verious morphologies were successfully fabricated via a single nozzle electrospinning method and subsequent calcination process. The matter diffusion in calcination ... więcej

One dimensional metal oxide materials with verious morphologies were successfully fabricated via a single nozzle electrospinning method and subsequent calcination process. The matter diffusion in calcination process plays an important role for the morphology. With low heating rate of 1 or 5 degrees C/min, SnO2 samples tended to form solid nanofibers consisted of small nanoparticles with uniform size. Using same conditions, CeO2 samples preferred to form belt morphology while Co3O4 tended to form a chain. This is ascribed to the difference of diffusion of these metal oxides during calcination. To fabricate hollow fibers, a two-step calcination route was used. A heating rate of 1 degrees C/min was used at less than 300 degrees C to create dense solid fiber. Low heating rate at low temperature could be beneficial to enhancing Kirkendall effect remarkably. A heating rate of 15 degrees C/min was used during temperature rising from 300 to 550 degrees C, in which the quick decomposition of poly(vinylpyrrolidone) occurred. Such quick decomposition resulted in the fast diffusion of metal oxides to the surface layer of fibers. SnO2, CeO2, and SnO2/CeO2 hollow fibers were successfully fabricated through the two-step calcination. In addition, SnO2 and Co3O4 tended to form on SnO2/CeO2 and Co3O4/CeO2 composite structure during calcination process.