Formation mechanism of porous hollow SnO2 nanofibers prepared by one-step electrospinning
eXPRESS Polymer Letters
The present study investigates the formation mechanism of hollow SnO 2 nanofibers and the form of nanograin growth in nanofibers. SnO 2 hollow nanofibers were fabricated by directly annealing electrospun polyvinylpyrrolidone (PVP)/Sn precursor composite nanofibers. In this approach, an appropriate proportion of PVP/Sn precursor with co-solvents established a system to form core/shell PVP/Sn precursor structure, and then PVP was decomposed quickly which acted as sacrificial template to keep
... mplate to keep fibrous structure and there existed a Sn precursor/SnO 2 concentration gradient to form hollow SnO 2 nanofibers due to the Kirkendall effect and surface diffusion during the calcination process. This deduction was also confirmed by experimental observations using transmission electron microscopy. The study suggested that surface diffusion and lattice diffusion were both driving force for nanograin growth on the surface of SnO 2 nanofibers. As supporting evidence, the tetragonal rutile SnO 2 hollow nanofibers were also characterized by X-ray diffraction, scanning electron microscopy and Brunauer-Emmett-Teller analysis.