Activity engineering of cobalt-based oxide materials for high performance supercapacitors: from morphology regulation to structural optimization

Abstract

Supercapacitors (SCs) have been considered as promising energy storage devices owing to their high power density, short charge–discharge time and long cycle life. Benefiting from high specific capacitance, cobalt-based oxides, as advanced electrode materials, are expected to improve the electrochemical properties of SCs. In view of their poor electrical conductivity and serious agglomeration during the reaction, many effective strategies have been developed to solve these issues, thus improving the electrochemical properties. Herein, recent advances in activity engineering of cobalt-based oxide materials are summarized in two aspects: regulation of morphology by synthesis methods and structural optimization by compositing with other materials to form composites. Particularly, the influence of synthesis methods and composite types on the morphology and structure is discussed in detail to reveal the morphology–structure–performance relationship. Finally, the future challenges and perspectives of cobalt-based oxides for SCs are provided.