This article reported the electrochemical performance of a novel cabon microsphere/MnO2nanosheets(CMS/MnO2) composite prepared by a in situ self-limiting deposition method under hydrothermal condition. The results of ...This article reported the electrochemical performance of a novel cabon microsphere/MnO2nanosheets(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 MnO2nanosheets 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 MnO2active 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/MnO2composite presented high capacitance of 181 F g-1and long cycle life of 61% capacity retention after 2000 charge/discharge cycles in 1 mol/L Na2SO4solution, which show strong promise for high-rate electrochemical capacitive energy storage applications.展开更多
Microflowers made of interconnected MnO2 nanosheets have been successfully synthesized in a microwave reactor through a hydrothermal reduction of KMnO4 with aqueous HCI at elevated temperatures in the presence of supe...Microflowers made of interconnected MnO2 nanosheets have been successfully synthesized in a microwave reactor through a hydrothermal reduction of KMnO4 with aqueous HCI at elevated temperatures in the presence of superparamagnetic Fe3O4SiO2 core-shell nanoparticles.Due to the chemical compatibility between SiO2 and MnO2,the heterogeneous reaction leads to the spontaneous encapsulation of the Fe3O4@SiO2 core-shell nanoparticles in the MnO2 microflowers.The resulting hybrid particles exhibit multiple properties including high surface area associated with the MnO2nanosheets and superparamagnetism originated from the Fe3O4@SiO2 core-shell nanoparticles.which are beneficial for applications requiring both high surface area and magnetic separation.展开更多
基金supported by the National Natural Science Foundation of China(No.51363014,51362018,51203071 and 21163010)the Key Project of Chinese Ministry of Education(No.212183)the Natural Science Funds for Distinguished Young Scholars of Gansu Province(No1111RJDA012)
文摘This article reported the electrochemical performance of a novel cabon microsphere/MnO2nanosheets(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 MnO2nanosheets 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 MnO2active 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/MnO2composite presented high capacitance of 181 F g-1and long cycle life of 61% capacity retention after 2000 charge/discharge cycles in 1 mol/L Na2SO4solution, which show strong promise for high-rate electrochemical capacitive energy storage applications.
基金supported by the U.S.Department of Energy,Office of Science,Office of Basic Energy Sciences,under Contract No.DE-AC02-06CH11357
文摘Microflowers made of interconnected MnO2 nanosheets have been successfully synthesized in a microwave reactor through a hydrothermal reduction of KMnO4 with aqueous HCI at elevated temperatures in the presence of superparamagnetic Fe3O4SiO2 core-shell nanoparticles.Due to the chemical compatibility between SiO2 and MnO2,the heterogeneous reaction leads to the spontaneous encapsulation of the Fe3O4@SiO2 core-shell nanoparticles in the MnO2 microflowers.The resulting hybrid particles exhibit multiple properties including high surface area associated with the MnO2nanosheets and superparamagnetism originated from the Fe3O4@SiO2 core-shell nanoparticles.which are beneficial for applications requiring both high surface area and magnetic separation.
