Abstract:

A new carbon-coated SnO₂ hollow fiber was successfully prepared by coaxial electrospinning, and its supercapacitor properties were well studied. The surface morphology and structure were examined using X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and the Brunauer-Emmett-Teller (BET) method. The results showed hollow fibers of average diameter 1 μm and carbon-coated SnO₂ particles of average size 3-15 nm uniformly distributed on the fiber shell. The surface area was 565 m²·g^-1. In a three-electrode system, the electrode achieved a respectable specific capacitance of 397.5 F·g^-1 at 0.25 A·g^-1, and the capacitance retained ratio was still 88% of the initial value after 3000 cycles at 1.0 A·g^-1. In the case of a symmetrical two-electrode system, the electrode achieved a specific capacitance of 162.0 F·g^-1 at 0.25 A·g^-1 current density, and the capacitance retained ratio was 84% of the initial value after 3000 cycles at 1.0 A·g^-1.

Key words: Coaxial electrospinning, Carbon-coated nano-SnO₂, Hollow structure, Supercapacitor