Realizing n-Type Field-Effect Performance via Introducing Trifluoromethyl Groups into the Donor–Acceptor Copolymer Backbone

• DOI: 10.1021/acs.macromol.9b00022
• Publication Date: 2019-03-21T14:34:59Z
• Authors: Congyuan Wei; Weifeng Zhang; Jianyao Huang; Hao Li; Yankai Zhou; Gui Yu
• Keywords: HOMO/LUMO; Acceptor; Electron Mobility; Electron acceptor

Developing a new strategy to obtain n-type organic semiconductors is crucial for the advance of electronics. We herein report synthesis and investigation series donor–acceptor-type diazaisoindigo-based copolymers, named PAIID-TFBVB-C1, PAIID-TFBVB-C3, PAIID-BVB-C3. After introduction trifluoromethyl groups with strong electron-withdrawing ability into molecular backbone PAIID-BVB-C3-containing stilbene units, obtained polymer PAIID-TFBVB-C3 shows obvious blue-shifted UV–vis absorption profiles because enlarged band gap revealed by theoretical simulation. Meanwhile, both energy levels lowest unoccupied orbital (LUMO) PAIID-TFBVB-C1 are lower than that PAIID-BVB-C3 without groups, reducing difference between LUMO level work function source-drain electrode further facilitating electron injection. Consequently, PAIID-TFBVB-C1- PAIID-TFBVB-C3-based devices show typical field-effect performance mobilities 0.11 0.04 cm2 V–1 s–1, respectively, whereas based on exhibit p-type semiconducting hole mobility 0.14 s–1. Our results demonstrate it feasible acquire materials introducing backbone.