Boosting capacitive performance of manganese oxide nanorods by decorating with three-dimensional crushed graphene
Akter Hossain Reaz, Shimul Saha, Chanchal Kumar Roy, Md A. Wahab, Geoffrey Will, Mohammed A. Amin, Yusuke Yamauchi, Shude Liu, Yusuf Valentino Kaneti, Md. Shahriar A. Hossain, Shakhawat H. Firoz
Abstract
Abstract This work reports the rational design of MnO x nanorods on 3D crushed reduced graphene oxide (MnO x /C-rGO) by chemical reduction of Ni-incorporated graphene oxide (GO) followed by chemical etching to remove Ni. The resulting MnO x /C-rGO composite synergistically integrates the electronic properties and geometry structure of MnO x and 3D C-rGO. As a result, MnO x /C-rGO shows a significantly higher specific capacitance ( C sp ) of 863 F g −1 than MnO x /2D graphene sheets (MnO x /S-rGO) (373 F g −1 ) and MnO x (200 F g −1 ) at a current density of 0.2 A g −1 . Furthermore, when assembled into symmetric supercapacitors, the MnO x /C-rGO-based device delivers a higher C sp (288 F g −1 ) than MnO x /S-rGO-based device (75 F g −1 ) at a current density of 0.3 A g −1 . The superior capacitive performance of the MnO x /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 MnO x /C-rGO. In addition, the MnO x /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. Graphical Abstract