Ultrahigh-Power Pseudocapacitors Based on Ordered Porous Heterostructures of Electron-Correlated Oxides.

Xing‐You Lang,Zi Wen,Bo‐Tian Liu,Qing Jiang,Xiang‐Mei Shi,Ying‐Qi Li

doi:10.1002/advs.201500319

Xing‐You Lang, Zi Wen + Show 4 more

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https://doi.org/10.1002/advs.201500319

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Abstract

Nanostructured transition‐metal oxides can store high‐density energy in fast surface redox reactions, but their poor conductivity causes remarkable reductions in the energy storage of most pseudocapacitors at high power delivery (fast charge/discharge rates). Here it is shown that electron‐correlated oxide hybrid electrodes made of nanocrystalline vanadium sesquioxide and manganese dioxide with 3D and bicontinuous nanoporous architecture (NP V2O3/MnO2) have enhanced conductivity because of metallization of electron‐correlated V2O3 skeleton via insulator‐to‐metal transition. The conductive V2O3 skeleton at ambient temperature enables fast electron and ion transports in the entire electrode and facilitates charge transfer at abundant V2O3/MnO2 interface. These merits significantly improve the pseudocapacitive behavior and rate capability of the constituent MnO2. Symmetric pseudocapacitors assembled with binder‐free NP V2O3/MnO2 electrodes deliver ultrahigh electrical powers (up to ≈422 W cm23) while maintaining the high volumetric energy of thin‐film lithium battery with excellent stability.

Highlights

Nanostructured transition-metal oxides can store high-density energy in fast advantageous features enlist pseudosurface redox reactions, but their poor conductivity causes remarkable reductions in the energy storage of most pseudocapacitors at high power delivery
We report a classic strongly correlated TMO, vanadium sesquioxide (V2O3), with a 3D bicontinuous nanoporous architecture (NP V2O3) as a conductive network penetrating in all-ceramic hybrid electrodes of V2O3/MnO2 (NP V2O3/MnO2) for high-performance pseudocapacitors
Our strategy to fabricate porous electrodes of heterostructured electron-correlated oxides makes use of periodic opal and inverse opal templates,[24,40] on which vanadium and manganese oxides are consecutively electrodeposited to produce 3D bicontinuous NP V2O3/MnO2 electrodes

Summary

Introduction

Nanostructured transition-metal oxides can store high-density energy in fast advantageous features enlist pseudosurface redox reactions, but their poor conductivity causes remarkable reductions in the energy storage of most pseudocapacitors at high power delivery (fast charge/discharge rates). The conductive V2O3 skeleton at ambient temperature enables fast electron and ion transports in the entire electrode and facilitates charge transfer at abundant V2O3/MnO2 interface. These merits significantly improve the pseudocapacitive behavior from state-of-the-art electrode materials, typically transition-metal oxides (TMOs) such as MnO2,[5,15,19,20] TiO2,[6,16] and Co3O4,[19,21] often exhibit much lower power capability than EDLCs due to their intrinsically poor conductivity.[15,21] It and rate capability of the constituent MnO2. With fast-growing demands for energy storage devices that can TMO-based composite electrodes,[1,6,17,23,25] wherein various store/deliver high-density energy at rapid charge/discharge conductive materials, including nanostructured carbons (such as rates,[1,2] enormous research interest has recently been stimu- porous carbon,[14,26] carbon nanotubes,[27,28,29,30] and graphene [31,32])

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