Electrochemical energy storage performance of heterostructured SnO2@MnO2 nanoflakes

In this work, we report synthesis of SnO2@MnO2 nanoflakes grown on nickel foam through a facile two-step hydrothermal route. The as-obtained products are characterized by series of techniques such as scanning electron microscopy (SEM), X-ray diffraction spectroscopy (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The as-obtained SnO2@MnO2 nanoflakes are directly used as supercapacitor electrode materials. The results show that the electrode possesses a high discharge areal capacitance of 1231.6 mF cm−2 at 1 mA cm−2 and benign cycling stability with 67.2% of initial areal capacitance retention when the current density is 10 mA cm−2 after 6000 cycles. Moreover, the heterostructured electrode shows 41.1% retention of the initial capacitance when the current densities change from 1 to 10 mA cm−2, which reveals good rate capability. SnO2@MnO2 nanoflakes products which possess excellent electrochemical properties might be used as potential electrode materials for supercapacitor applications.