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Abstract All‐solid‐state rechargeable sodium (Na)‐ion batteries are promising for inexpensive and high‐energy‐density large‐scale energy storage. In this contribution, new Na solid electrolytes, Na3−yPS4−xClx, are synthesized with a strategic approach, which allows maximum substitution of Cl for S (x= 0.2) without significant compromise of structural integrity or Na deficiency. A maximum conductivity of 1.96 mS cm−1at 25 °C is achieved for Na3.0PS3.8Cl0.2, which is two orders of magnitude higher compared with that of tetragonal Na3PS4(t‐Na3PS4). The activation energy (Ea) is determined to be 0.19 eV. Ab initio molecular dynamics simulations shed light on the merit of maximizing Cl‐doping while maintaining low Na deficiency in enhanced Na‐ion conduction. Solid‐state nuclear magnetic resonance (NMR) characterizations confirm the successful substitution of Cl for S and the resulting change of P oxidation state from 5+ to 4+, which is also verified by spin moment analysis. Ion transport pathways are determined with a tracer‐exchange NMR method. The functional detects that promote Na ‐ion transport are maximized for further improvement in ionic conductivity. Full‐cell performance is demonstrated using Na/Na3.0PS3.8Cl0.2/Na3V2(PO4)3with a reversible capacity of ≈100 mAh g‐1at room temperature.
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Local Glass Transition Temperature T g ( z ) Profile in Polystyrene next to Polybutadiene with and without Plasticization Effects
Abstract Rubber toughening of glassy polystyrene (PS) has been manufactured commercially for decades as high impact polystyrene, where rubbery poly‐butadiene (PB) inclusions are added to modify the PS matrix response to deformation and impact. In this study, measurements of the local glass transition temperatureTg(z) of PS next to PB rubber are presented, expanding the previous data to a polymer with a much lowerTgvalue (PBTgbulk= −96 °C). After accounting for a small molecule additive present in the commercial PB sample that would otherwise migrate over to the PS domain causing plasticization, it is found that theTg(z) profile in PS next to PB is consistent with previous results. It is also demonstrated that these broad and asymmetric experimentally observedTg(z) profiles are not caused by the migration of low molecular weight chains across the interface by comparing samples made with two different poly(n‐butyl methacrylate) molecular weights.
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- PAR ID:
- 10047116
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Macromolecular Chemistry and Physics
- Volume:
- 219
- Issue:
- 3
- ISSN:
- 1022-1352
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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