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Abstract N‐Type thermoelectrics typically consist of small molecule dopant+polymer host. Only a few polymer dopant+polymer host systems have been reported, and these have lower thermoelectric parameters. N‐type polymers with high crystallinity and order are generally used for high‐conductivity () organic conductors. Few n‐type polymers with only short‐range lamellar stacking for high‐conductivity materials have been reported. Here, we describe an n‐type short‐range lamellar‐stacked all‐polymer thermoelectric system with highestof 78 S−1, power factor (PF) of 163 μW m−1 K−2, and maximum Figure of merit (ZT) of 0.53 at room temperature with a dopant/host ratio of 75 wt%. The minor effect of polymer dopant on the molecular arrangement of conjugated polymer PDPIN at high ratios, high doping capability, high Seebeck coefficient (S) absolute values relative to, and atypical decreased thermal conductivity () with increased doping ratio contribute to the promising performance.
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Structural Diversity and Magnetic Properties of Hybrid Ruthenium Halide Perovskites and Related Compounds
Abstract There has been a great deal of recent interest in extended compounds containing Ru3+and Ru4+in light of their range of unusual physical properties. Many of these properties are displayed in compounds with the perovskite and related structures. Here we report an array of structurally diverse hybrid ruthenium halide perovskites and related compounds: MA2RuX6(X=Cl or Br), MA2MRuX6(M=Na, K or Ag;X=Cl or Br) and MA3Ru2X9(X=Br) based upon the use of methylammonium (MA=CH3NH3+) on the perovskite A site. The compounds MA2RuX6with Ru4+crystallize in the trigonal space groupand can be described as vacancy‐ordered double‐perovskites. The ordered compounds MA2MRuX6with M+and Ru3+crystallize in a structure related to BaNiO3with alternatingMX6and RuX6face‐shared octahedra forming linear chains in the trigonalspace group. The compound MA3Ru2Br9crystallizes in the orthorhombic Cmcm space group and displays pairs of face‐sharing octahedra forming isolated Ru2Br9moieties with very short Ru–Ru contacts of 2.789 Å. The structural details, including the role of hydrogen bonding and dimensionality, as well as the optical and magnetic properties of these compounds are described. The magnetic behavior of all three classes of compounds is influenced by spin–orbit coupling and their temperature‐dependent behavior has been compared with the predictions of the appropriate Kotani models.
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- Award ID(s):
- 1729489
- PAR ID:
- 10156051
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 59
- Issue:
- 23
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 8974-8981
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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