Blended Conjugated Host and Unconjugated Dopant Polymers Towards N‐type All‐Polymer Conductors and High‐ZT Thermoelectrics
Jinfeng Han, Yufeng Jiang, Emma Tiernan, Connor Ganley, Yunjia Song, Taein Lee, Arlene Chiu, Patty McGuiggan, Nicholas Adams, Paulette Clancy, Thomas P. Russell, Patrick E. Hopkins, Susanna M. Thon, John D. Tovar, Howard E. Katz
Abstract
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 highest of 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.