No abstract

A detailed chemical/structural composition and electrochemical study of Li insertion in a manganese oxide phase with a tunnel (todorokite) framework and its 2D (birnessite/buserite) precursor is presented. The effect of ion substitution within the lattice and in the interstitial sites as a result of different methods of preparation was also examined for both structures. The results outline the effect of the arrangement of the MnO6 octahedra, the framework composition, and of thermal treatment of these inorganic host structures on the electrochemical response. At intermediate cycling rates, todorokite displays the highest discharge capacity of 0.6 Li/Mn (155 mAh/g) down to 2.0 V, and 0.52 Li/Mn reversible capacity in the voltage window 4.2-2.0 V. There is one primary site for Li insertion within the large tunnels, along with a secondary site of lesser capacity. Differences in the two preparation methods lead to pronounced differences in the ability to remove ions from within the structure, although the overall reversible capacities of the resultant materials are similar. These results are interpreted in the context of cation substitution within the framework structure of todorokite, and its relationship to the 2D frameworks that are precursors to its formation by hydrothermal methods.) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 130.88.90.140 Downloaded on 2015-04-13 to IP

SynopsisThe solubility parameters of sixteen polymers have been determined by the turbidi-The results agree well with the reported values obtained fromThe method is sensitive to the choice of nonmetric titration method. swelling and viscosity measurements. solvents and to small changes in the copolymer composition.

No abstract

No abstract