Boosting charge and thermal transport - role of insulators in stable and efficient n-type polymer transistors

Zhuoqiong Zhang, Johnny Ka Wai Ho, Chujun Zhang, Hang Yin, Zhenchuan Wen, Guilong Cai, Ruyan Zhao, Run Shi, Xinhui Lu, Jun Liu, Xiaotao Hao, Chun Cheng*, Shu Kong So*

*Corresponding author for this work

Research output: Contribution to journalJournal articlepeer-review

5 Citations (Scopus)


Conjugated polymers are promising materials for flexible electronics. However, some prominent challenges remain and limit further commercialization. Among these issues, n-type polymers are known to be prone to electron trappings, which may lead to heat localization, unsustainable transport and ultimately device failure. In this contribution, three n-type polymers with representative electron-transporting moieties, double B←N bridged bipyridine (BNBP), naphthalene-diimide (NDI), and perylene-diimide (PDI), are selected and intentionally blended with a small amount of insulating polymer polystyrene (PS). In an organic field-effect transistor (OFET) structure, the blended semiconductors are shown to possess enhanced electron mobilities and device durability. The origin of the improved performance is investigated. Despite the thermally and electrically insulating properties of bulk PS, the blend films show improved heat transfer and electronic properties as revealed by scanning photothermal deflection and time-resolved photoluminescence. The counter-intuitive outcome is rationalized by a microstructure model in which PS blends inhomogeneously with the semiconductors. The added PS tends to mix with the amorphous phase, passivates phonons and charge trappings, and offers more efficient phonon and electron transport pathways. This work provides mechanistic insights into clinical device performance enhancement for semiconductor/insulator blends.

Original languageEnglish
Pages (from-to)12281-12290
Number of pages10
JournalJournal of Materials Chemistry C
Issue number36
Early online date26 Jul 2021
Publication statusPublished - 28 Sept 2021

Scopus Subject Areas

  • Chemistry(all)
  • Materials Chemistry


Dive into the research topics of 'Boosting charge and thermal transport - role of insulators in stable and efficient n-type polymer transistors'. Together they form a unique fingerprint.

Cite this