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This content will become publicly available on April 20, 2023

Title: A New Polystyrene–Poly(vinylpyridinium) Ionic Copolymer Dopant for n‐Type All‐Polymer Thermoelectrics with High and Stable Conductivity Relative to the Seebeck Coefficient giving High Power Factor
A novel n-type copolymer dopant polystyrene-polyvinyl hexylpyridinium fluoride (PSpF) with fluoride anion is designed and synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization. To our knowledge, it is the first polymeric fluoride dopant. Electrical conductivity of 4.2 S cm-1 and high power factor of 67 μW m-1 K-2 are achieved for PSpF doped polymer films, with a corresponding decrease in thermal conductivity as the PSpF concentration is increased, giving the highest ZT of 0.1. An especially high electrical conductivity of 58 S cm-1 at 88 ℃ and outstanding thermal stability were recorded. Further, organic transistors of PSpF-doped thin films exhibit high electron mobility and Hall mobility of 0.86 and 1.70 cm2 V-1 s-1, respectively. The results suggest that polystyrene-polyvinyl pyridinium salt copolymers with fluoride anion are promising for high performance n-type all-polymer thermoelectrics. This work provides a new way to realize organic thermoelectrics with high conductivity relative to Seebeck coefficient, high power factor, thermal stability and broad processing window.
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Award ID(s):
2107360 1708245
Publication Date:
Journal Name:
Advanced Materials
Page Range or eLocation-ID:
Sponsoring Org:
National Science Foundation
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