CeO2-clay composites for ultra-long cycle life electrochemical capacitive energy storage application

Abstract

The lattice expansion caused by the reduction of Ce(IV) to Ce(III) impeded the development of the CeO2 as an effective electrode material for electrochemical supercapacitors. Herein, we prepared CeO2-clay composites through a one-step hydrothermal method. The interlayer structures of clays efficiently accommodate volume changes induced by crystal lattice expansion to achieve ultra-long cycle stability. After 60000 charge–discharge cycles, the capacitance retention rate of the assembled asymmetric supercapacitors is as high as ∼100%. The key findings of this work reveal the potential application of clays in achieving ultralong cycle stability of the CeO2 electrode material, paving the way for further application of the CeO2 in electrochemical energy storage.