SnO2 nanospheres and V2O5/SnO2 nanoparticles with mesoporous structures for flexible asymmetric supercapacitors

Carbon fibers' textile (CFT)-based flexible electrodes containing a large number of SnO2 nanospheres and V2O5/SnO2 nanoparticles were obtained by a facile one-pot template method. The homogeneously distributed SnO2 and V2O5/SnO2 exhibit an optimized worm-like mesoporous skeleton and an ideal pore size distribution with a highest surface area of around 295.5 m(2)center dot g(-1) and 198.0 m(2)center dot 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 V2O5/SnO2@CFT as the positive electrode and SnO2@CFT as the negative electrode with well-widened voltage windows. Benefiting from the 3D controllable mesoporous architecture of electroactive species, the assembled supercapacitors delivered a high specific capacitance of 151.3 F center dot g(-1) at 1 A center dot g(-1), and good rate stability with 70.9% capacitance retention at a higher current density of 5 A center dot g(-1). Notably, the device can operate in a wide voltage window (0 similar to 1.6 V), which enhance substantially the energy density to 193.6 Wh center dot kg(-1) at a power density of 2880 W center dot kg(-1). These encouraging results are 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.

Automated summary

Carbon fibers' textile (CFT)-based flexible electrodes with SnO2 nanospheres and V2O5/SnO2 nanoparticles were prepared. The electrodes exhibited optimized mesoporous structure and high surface area. A solid-state flexible asymmetric supercapacitor was fabricated using these electrodes and showed high specific capacitance and good rate stability.