Mechanistic Insights into Formation of SnO2 Nanotubes: Asynchronous Decomposition of Poly(vinylpyrrolidone) in Electrospun Fibers during Calcining Process

The formation mechanism of SnO2 nanotubes (NTs) fabricated by generic electrospinning and calcining was revealed by systematically investigating the structural evolution of calcined fibers, product composition, and released volatile byproducts. The structural evolution of the fibers proceeded sequentially from dense fiber to wire-in-tube to nanotube. This remarkable structural evolution indicated a disparate thermal decomposition of poly­(vinylpyrrolidone) (PVP) in the interior and the surface of the fibers. PVP on the surface of the outer fibers decomposed completely at a lower temperature (