Lamellar‐Paracrystallinity‐Controlled Thermal Transport in Polymer Semiconductors
Abstract
ABSTRACT Understanding thermal transport in polymer semiconductors is crucial for thermal management in organic electronic and energy‐harvesting devices, directly affecting their performance, safety and long‐term stability. However, the structure‐property relationship and underlying thermal transport physics remain largely unexplored. Herein, thermal conductivities of 11 representative polymer semiconductors were measured using an improved suspended‑3 ω technique, revealing a strong correlation between thermal conductivity and the paracrystalline disorder of lamellar packing. It is observed that the in‑plane intrinsic thermal conductivity of polymer semiconductor films is predominantly controlled by lamellar paracrystallinity, rather than backbone chemistry or π–π stacking. Tuning lamellar paracrystallinity within the same polymer modulated thermal conductivity by up to ∼40%. Our work shows that lamellar packing is the primary interchain thermal transport pathway, with more efficient vibrational coupling than π–π stacking as evidenced by molecular dynamics simulations. This physical picture reveals distinct interchain pathways for charge and thermal transport in polymer semiconductors, providing guidelines for manipulating thermal conductivity without affecting electrical performance in advanced organic materials and devices.
Article Details
Authors (7)
Nai‐Fu Liu
Beijing National Laboratory for Molecular Sciences (BNLMS) Center of Soft Matter Science and Engineering Key Laboratory of Polymer Chemistry and Physics of Ministry of Education College of Chemistry and Molecular Engineering Peking University Beijing China
Xiao‐Yan Zhang
Beijing National Laboratory for Molecular Sciences (BNLMS) Center of Soft Matter Science and Engineering Key Laboratory of Polymer Chemistry and Physics of Ministry of Education College of Chemistry and Molecular Engineering Peking University Beijing China
Yi‐Fan Huang
Beijing National Laboratory for Molecular Sciences (BNLMS) Center of Soft Matter Science and Engineering Key Laboratory of Polymer Chemistry and Physics of Ministry of Education College of Chemistry and Molecular Engineering Peking University Beijing China
Hao‐Tian Wu
Beijing National Laboratory for Molecular Sciences (BNLMS) Center of Soft Matter Science and Engineering Key Laboratory of Polymer Chemistry and Physics of Ministry of Education College of Chemistry and Molecular Engineering Peking University Beijing China
Ze‐Fan Yao
Beijing National Laboratory For Molecular Sciences (BNLMS) Key Laboratory of Polymer Chemistry and Physics of Ministry of Education Center For Soft Matter Science and Engineering College of Chemistry and Molecular Engineering Peking University Beijing China
Jie‐Yu Wang
Beijing National Laboratory of Molecular Sciences (BNLMS) College of Chemistry and Molecular Engineering Peking University Beijing 100871 China
Jian Pei