ISSN:
1572-8838
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Chemie und Pharmazie
,
Elektrotechnik, Elektronik, Nachrichtentechnik
Notizen:
Abstract Thirty-one samples of composition MnOOHr, where 0.1〈r〈1.0, were prepared under mild conditions by reacting a commercial electrodeposited manganese dioxide (EMD) with xylene, acetone, cinnamyl alcohol or combinations thereof. Although the X-ray pattern reflected the expected dilation of the crystal structure in the region 0.1〈r〈0.8 the attainment of an H insertion level of MnOOH0.8 without the emergence of additional peaks is a new finding. The expansion was nearly isotropic and careful examination of peak positions and intensities indicated changes in behaviour at aboutr=0.25 and 0.45. Another finding was the ability of inserted H to migrate across the boundaries of nominally dry powders in the region 0.1〈r〈0.8. In the regionr〉0.8 expansion was clearly anisotropic and as a consequence new diffraction peaks emerged and some of the peaks present at lower H insertion levels were substantially reduced in intensity. A particularly important observation was the restricted mobility shown by inserted H in the end-product MnOOH as this has implications for the performance of EMD in batteries. The X-ray diffraction pattern of the end-product was dissimilar to α- and γ-MnOOH in important respects and a previous suggestion that it is called δ-MnOOH seems preferable.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF01464293
