Pseudocapacitive effect and Li+ diffusion coefficient in three-dimensionally ordered macroporous vanadium oxide for energy storage

• Improved Li-ion Faradic kinetics was important for the high rate capability of 3DOM vanadia.
• Enhanced pseudocapacitive effect was found by cyclic voltammetry.
• Chronoamperometry showed the improved Li+ diffusion coefficient of 2.13 × 10− 10 cm2 s− 1.

In order to act as extrinsic pseudocapacitor materials, nanoscale vanadium oxides are required to simultaneously exhibit a capacitance-based high power density and an intercalation-based high energy density. We have fabricated a three-dimensionally ordered macroporous (3DOM) structure with a wall thickness of 14 nm that fulfills the above requirements. The 3DOM vanadium oxide film exhibits high rate performance with 355 F g− 1 at 0.5 A g− 1 and 125 F g− 1 at 15 A g− 1. The enhanced pesudocapacitive effect and Li-ion diffusion coefficient based on the 3DOM nanostructure, also contributes to the high rate capability of vanadia, which can be confirmed by cyclic voltammetry and chronoamperometry.

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