Microstructure of Nanocrystalline Electrolytic $MnO_2$ (EMD)

Nanocrystalline Electrolytic $MnO_2$ (EMD)의 미세구조 연구

  • ;
  • Anqiang He (Department of Chemical & Materials Engineering, University of Alberta) ;
  • Arthur H. Heuer (Department of Materials Science & Engineering)
  • Published : 2003.06.01


The microstructure of bulk electrolytic MnO₂ (EMD) was studied using x-ray diffraction and transmission electron microscopy (TEM). The bulk sample showed a typical powder x-ray diffraction pattern of EMD materials. TEM study showed that the structure of EMD is present at two length scales;grains, ∼0.2 ㎛ in diameter, and ∼10 nm crystallites within the grain. The electron beam microdiffraction study revealed that each grain is an assemblage of multiphase with a common crystallographic orientation, and_that ∼50% of the crystallites are Ramsdellite, ∼30% are ε-MnO₂, and ∼15% are Pyrolusite. The {1120}peak located at about 67° in powder XRD pattern as well as a high-resolution electron microscope (HREM) image of (0001) plane support the existence of ε-MnO₂ phase.



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