MnO2 nanosheets modified CoP/P-C core/shell nanotubes with vertically aligned channels for promoting supercapacitor performances

MnO 2 nanosheets modified CoP/P-C core/shell nanotubes with vertically aligned channels for promoting supercapacitor performances. • MnO 2 nanosheets modified CoP/P-C core/shell nanotube arrays are successfully prepared. • The CoP/P-C/MnO 2 @CC electrode shows the specific capacity of 742 F g −1 at 1 A g −1 . • The electrochemical performance of CoP/P-C@CC can be efficiently enhanced by the growth of MnO 2 nanosheets. • The CoP/P-C/MnO 2 @CC//AC supercapacitor delivers a high energy density of 93.12 Wh kg −1 at power density of 800 W kg −1 . Research into electrode materials that are low-cost, possess high capacity, and exhibit long cycle life is pivotal for the advancement of supercapacitor technology. Herein, a CoP/P-C/MnO 2 @CC composite is synthesized by solution impregnation and high temperature phosphating. The unique combination of nanotubes and MnO 2 nanosheets reduces ion and electron transmission distance and significantly increases active sites. The CoP/P-C/MnO 2 @CC electrode demonstrates a specific capacitance of 742.0 F g −1 at 1 A g −1 , a substantial improvement over the counterpart prior to KMnO 4 immersion (459.4 F g −1 ). Furthermore, an asymmetric supercapacitor based on the CoP/P-C/MnO 2 @CC electrode was assembled, achieving a high energy density of 93.12 Wh kg −1 at a power density of 800 W kg −1 . Meanwhile, the device maintains 77.3 % of its original capacity after 8000 cycles, demonstrating good cycle stability. This study not only presents an attractive electrode material with unique structure, but also provides a referential methodology for developing superior electrodes.