Boosting capacitive performance of manganese oxide nanorods by decorating with three-dimensional crushed graphene

This work reports the rational design of MnOx nanorods on 3D crushed reduced graphene oxide (MnOx/C-rGO) by chemical reduction of Ni-incorporated graphene oxide (GO) followed by chemical etching to remove Ni. The resulting MnOx/C-rGO composite synergistically integrates the electronic properties and geometry structure of MnOx and 3D C-rGO. As a result, MnOx/C-rGO shows a significantly higher specific capacitance (C-sp) of 863 F g(-1) than MnOx/2D graphene sheets (MnOx/S-rGO) (373 F g(-1)) and MnOx (200 F g(-1)) at a current density of 0.2 A g(-1). Furthermore, when assembled into symmetric supercapacitors, the MnOx/C-rGO-based device delivers a higher C-sp (288 F g(-1)) than MnOx/S-rGO-based device (75 F g(-1)) at a current density of 0.3 A g(-1). The superior capacitive performance of the MnOx/C-rGO-based symmetric device is attributed to the enlarged accessible surface, reduced lamellar stacking of graphene, and improved ionic transport provided by the 3D architecture of MnOx/C-rGO. In addition, the MnOx/C-rGO-based device exhibits an energy density of 23 Wh kg(-1) at a power density of 113 Wkg(-1), and long-term cycling stability, demonstrating its promising potential for practical application.

Automated summary

This work presents the rational design of MnOx nanorods on 3D crushed reduced graphene oxide (MnOx/C-rGO) through chemical reduction and etching. The resulting composite exhibits enhanced specific capacitance and superior capacitive performance, attributed to the integration of MnOx and 3D C-rGO.