| 1. |
|
|
| 2. |
- Edman, Ludvig, 1967-, et al.
(författare)
-
Effect of C60 as a Filler on the Morphology of Polymer−Salt Complexes Based on Poly(ethylene oxide) and LiCF3SO3
- 1999
-
Ingår i: Macromolecules. - : American Chemical Society (ACS). - 0024-9297 .- 1520-5835. ; 32:12, s. 4130-4133
-
Tidskriftsartikel (refereegranskat)abstract
- The inclusion of C60 as a filler in complexes of paly(ethylene oxide) (PEO) and LiCF3SO3 salt reduces the degree of crystallinity of the material at ambient temperature. The observed effects are manifested as changes in characteristic vibrational modes of the crystalline polymer in FT-Raman spectra over a range of temperatures. The introduction of relatively small amounts of C60 also stabilizes ionic substructures present in these systems. Interestingly, no internal modes of the C60 molecule are affected by dissolution in PEO or by the presence of varying amounts of LiCF3SO3 salt in the matrix. From the absence of a shift in the C60:s charge-transfer-sensitive Ag(2) mode, in particular, it appears as though C60 essentially acts as an inert filler in these complexes.
|
|
| 3. |
- Edman, Ludvig, et al.
(författare)
-
Electrical resistivity of single crystal graphite under pressure: an anisotropic 3-D semimetal
- 1998
-
Ingår i: Physical Review B. Condensed Matter and Materials Physics. - : American Physical Society. - 1098-0121 .- 1550-235X. ; 57:11, s. 6227-6230
-
Tidskriftsartikel (refereegranskat)abstract
- The in-plane (ρa) and c-axis (ρc) resistivities of natural single-crystal graphite have been measured from 4 to 450 K at zero pressure and from 77 to 450 K under pressures up to 500 MPa. Data for ρc differ strongly from earlier results obtained on synthetic graphite in showing a strong T dependence of the pressure coefficient, while data for ρa agree well with those from previous studies. Our results can be analyzed quantitatively in a simple free-electron model, and we conclude that in contrast to quasi-two-dimensional synthetic graphite, natural single-crystal graphite is an anisotropic three-dimensional semimetal.
|
|
| 4. |
- Edman, Ludvig, et al.
(författare)
-
Sodium-sodium halide co-intercalated graphite: chemistry, structure and electrical transport
- 1999
-
Ingår i: Journal of Physics and Chemistry of Solids. - : Elsevier B.V.. - 0022-3697 .- 1879-2553. ; 60:4, s. 475-482
-
Tidskriftsartikel (refereegranskat)abstract
- This study deals with the second to fourth stage compounds resulting from the co-intercalation of sodium and sodium halides into graphite. The charge transfer was determined through chemical analyses and X-ray diffraction and the results are compatible with Raman spectroscopy data. We present detailed results on c axis conduction between 4.2 K and 295 K and for hydrostatic pressures as high as 1.6 GPa. Possible mechanisms explaining the c axis conduction are discussed.
|
|
| 5. |
- Ferry, Anders, et al.
(författare)
-
Connectivity, ionic interactions, and migration in a fast-ion-conducting polymer-in-salt electrolyte based on poly(acrylonitrile) and LiCF3SO3
- 1999
-
Ingår i: Journal of Applied Physics. - : American Institute of Physics (AIP). - 0021-8979 .- 1089-7550. ; 86:4, s. 2346-2348
-
Tidskriftsartikel (refereegranskat)abstract
- The ionic conductivity of a polymeric fast-ion-conductor based on LiCF3SO3 salt and poly(acrylonitrile), [CH2CH(CN)]n), is enhanced by ∼5 orders of magnitude when the composition approaches the "polymer-in-salt" regime; i.e., when the salt content increases from N:Li=12:1 to 1.2:1 (or ∼70 wt % of salt). This is in contrast to common salt-in-polymer electrolytes where a conductivity maximum typically is encountered at intermediate compositions. We suggest that connectivity effects in a microscopically phase segregated material may influence the long-range migration of charge carriers. Conductivity data are augmented with Raman spectroscopic investigations, thus probing microscopic details regarding the state of the dissolved salt.
|
|
| 6. |
|
|
