Facile Construction of Sno2 Nanospheres and V2o5/Sno2 Nano Particles with Mesoporous Structures for Superior-Performances Flexible Asymmetric Supercapacitors

Abstract

Carbon fibers textile (CFT) based flexible electrodes containing a large number of SnO 2 nanospheres and V 2 O 5 /SnO 2 nanoparticles were obtained by a facile one-pot template method. The homogeneously distributed SnO 2 and V 2 O 5 /SnO 2 exhibit an optimized wormlike mesoporous skeleton and an ideal pore size distribution with a high surface area of around 295.5 m 2 ·g -1 and 198.0 m 2 ·g -1 , respectively. Using the mesoporous transition/mixed transition metal oxide nanomaterials simultaneously as both positive and negative electrodes, a solid-state flexible asymmetric supercapacitor was fabricated with the V 2 O 5 /SnO 2 @CFT as the positive electrode and SnO 2 @CFT as the negative electrode with well-widened voltage windows. Benefiting from the 3D controllable mesoporous architecture of electroative species, the assembled supercapacitors delivered a high specific capacitance of 187.5 F·g -1 at 1 A·g -1 , and good rate stability with 63.4 % capacitance retention at a higher current density of 5 A·g -1 . Notably, the device can operate in a wide voltage window (-1.0~0.6 V), which enhance substantially the energy density to 240.0 Wh·kg -1 at a power density of 2880 W·kg -1 . These encouraging results is expected to open up a possibility of designing and fabricating the other metal oxide nanomaterials with mesoporous structure and uniform morphology for high-performance supercapacitors and other energy storage devices application.

Keywords: Mesoporous structure, V2O5/SnO2, SnO2, Flexible asymmetric supercapacitors