Hollow FeOOH nanorods decorated with MnO2 nanosheets as electrode materials for high-performance asymmetric supercapacitors

Nano core–shell structured materials have different or better properties than single components, which can realize the design and optimization of nanoscale particle structure and properties. Additionally, hollow core–shell materials have the advantages of large specific surface area, abundant active sites, low density, short mass transfer path, and wide cavity structure, which are widely used in the fields of electrochemistry, biomedicine, and environmental protection. Herein, hollow core–shell FeOOH@MnO 2 nanorod composites were prepared by easiest hydrothermal method. Due to the synergy and versatility between the hollow FeOOH nanorods core and the MnO 2 nanosheets shell, the FeOOH@MnO 2 composite exhibits outstanding electrochemical characteristic as an electrode material with specific capacitance of 924 F g −1 at 1 A g −1 , admirable rate capability (capacitance retention of 75.9% from 1 to 10 A g −1 ), and remarkable cycling stability (91.2% of initial capacity retained after 5000 charge/discharge cycles). Notably, the assembled FeOOH@MnO 2 //activated carbon (AC) asymmetric supercapacitor facility possessed an energy density of 53.4 Wh kg −1 and a power density of 722 W kg −1 , indicating that the hollow core–shell FeOOH@MnO 2 nanorod nanocomposite is a viable electrode material that can be used in supercapacitors.