A dandelion-like carbon microsphere/MnO2 nanosheets composite for supercapacitors

This article reported the electrochemical performance of a novel cabon microsphere/MnO2 nanosheets (CMS/MnO2) composite prepared by a in situ self-limiting deposition method under hydrothermal condition. The results of scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed that MnO2 nanosheets homogeneously grew onto the surface of CMS to form a loose-packed and dandelion-like core/shell microstructure. The unique microstructure plays a basic role in electrochemical accessibility of electrolyte to MnO2 active material and a fast diffusion rate within the redox phase. The results of cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectrometry indicated that the prepared CMS/MnO2 composite presented high capacitance of 181 F·g−1 and long cycle life of 61% capacity retention after 2000 charge/discharge cycles in 1 mol/L Na2SO4 solution, which show strong promise for high-rate electrochemical capacitive energy storage applications.

Graphical AbstractA dandelion-like carbon microsphere/MnO2 nanosheet composite was prepared by a situ self-limiting deposition method under hydrothermal condition and a maximum specific capacitance of 187 F/g was obtained in 1 mol/L Na2SO4 aqueous solution.Figure optionsDownload as PowerPoint slide