Carbon/lambda-MnO{sub 2} composites for supercapacitor electrodes

Journal Article · Thu Apr 15 00:00:00 EDT 2010 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2010.02.015· OSTI ID:21372580

Malak-Polaczyk, A ^[1]; Matei-Ghimbeu, C; Vix-Guterl, C ^[2]; Frackowiak, E ^[1]

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1. Institute of Chemistry and Technical Electrochemistry, Poznan University of Technology, Piotrowo 3, 60-695 Poznan (Poland)
2. Institut de Sciences des Materiaux de Mulhouse, CNRS LRC 7228, 15 Rue Starcky, 68057 Mulhouse (France)

In the present work a composite of carbon with lambda-MnO{sub 2} have been synthesized by a simple two-step route. In the first step, to obtain LiMn{sub 2}O{sub 4}/carbon material, mesoporous activated carbon was impregnated with the solution of precursor metal salts and heated subsequently. As-prepared materials were acid treated which resulted in the formation of lambda-MnO{sub 2}/carbon. Physical properties, structure and specific surface area of electrode materials were studied by TEM, X-ray diffraction and nitrogen sorption measurements. Voltammetry cycling, galvanostatic charge/discharge and impedance spectroscopy measurements performed in two- and three-electrode cells have been applied in order to measure electrochemical parameters. TEM images confirmed well dispersed lambda-MnO{sub 2} particles on the surface of carbon material. The carbon in the composite plays an important role as the surface area enhancing component and a support of pseudocapacitive material. Furthermore, the through-connected porosity serves as a continuous pathway for electrolyte transport. A synergetic effect of the porous carbon framework and of the redox properties of the lambda-MnO{sub 2} is at the origin of improvement of specific capacitance values which has been observed for composites after delithiation. - Comparison of capacitance characteristics for initial carbon and synthesised composites for CB in 1 mol L{sup -1} Na{sub 2}SO{sub 4} solution.

• OSTI ID: 21372580
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 4 Vol. 183; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ACTIVATED CARBON
ADSORBENTS
ALKALI METAL COMPOUNDS
CARBON
CHALCOGENIDES
CHEMISTRY
COHERENT SCATTERING
DIFFRACTION
ELECTROCHEMISTRY
ELECTRODES
ELECTROLYTES
ELECTRON MICROSCOPY
ELEMENTS
IMPEDANCE
LITHIUM COMPOUNDS
MANGANESE COMPOUNDS
MANGANESE OXIDES
MATERIALS
MICROSCOPY
NANOSTRUCTURES
NONMETALS
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
POROSITY
POROUS MATERIALS
SCATTERING
SODIUM COMPOUNDS
SODIUM SULFATES
SORPTION
SPECIFIC SURFACE AREA
SPECTROSCOPY
SULFATES
SULFUR COMPOUNDS
SURFACE AREA
SURFACE PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TRANSMISSION ELECTRON MICROSCOPY
VOLTAMETRY
X-RAY DIFFRACTION