title: Synthesis of flake-like MnO2/CNT composite nanotubes and their applications in electrochemical capacitors.
abstract: MnO2/CNT composite nanotubes with nanometer-sized flake-like MnO2 on carbon nanotubes' surfaces have been synthesized through an easy and efficient solution-based method. Similarly, Mn3O4/CNT composite nanotubes have also been synthesized by using the same method but different heat treatment process. The structures and compositions of the two types of composite nanotubes are characterized by using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and nitrogen adsorption-desorption isotherms. Electrochemical measurements indicate that the MnO2/CNT composites nanotubes exhibit significantly enhanced supercapacitance performance compared with the Mn3O4/CNT composite nanotubes, the as-synthesized MnO2 nanoparticles and commercial MnO2. The possibilities of the enhanced properties are illustrated on the basis of analysis of XRD and X-ray photoelectron spectroscopy measurements. Our results presented here can give clear evidence of the superiority of nanocrystalline MnO2 to nanocrystalline Mn3O4 toward the applications as electrode materials in electrochemical capacitors.
authors: Key Laboratory of Molecular Nanostructure and Nanotechnology, and Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing 100190, China.
authors: Rong-Rong
authors: RR
authors: Bi
authors: Ya-Xia
authors: YX
authors: Yin
authors: Yu-Guo
authors: YG
authors: Guo
authors: Li-Jun
authors: LJ
authors: Wan
mesh_terms: D003460:Crystallization / Q000379:methods*; D025802:Electric Capacitance; D004563:Electrochemistry / Q000295:instrumentation; D004566:Electrodes; D004867:Equipment Design; D019544:Equipment Failure Analysis; D046911:Macromolecular Substances / Q000138:chemical synthesis; D017895:Manganese Compounds / Q000737:chemistry*; D008422:Materials Testing; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D010316:Particle Size; D013499:Surface Properties
chemical_list: D046911:Macromolecular Substances; D017895:Manganese Compounds; D037742:Nanotubes, Carbon; D010087:Oxides; C027424:manganese oxide