Unravelling the Role of Electron Acceptors for the Universal Enhancement of Charge Transport in Quinoid-Donor-Acceptor Polymers for High-Performance Transistors

The quinoid-donor-acceptor (Q-D-A) strategy has recently emerged as a promising approach for constructing high mobility semiconducting polymers. In order to fully explore the potential of this strategy in improving the charge transport and elucidating the structure-property-performance relationships in Q-D-A polymers, a series of new polymers with different electron acceptor units and backbone coplanarity have been synthesized and characterized. All of the resulting Q-D-A polymers exhibit much more planar backbone conformations in comparison to their donor-acceptor (D-A) counterparts. Moreover, organic field-effect transistors based on Q-D-A polymers exhibit excellent effective hole mobilities in a range of 0.44 to 3.35 cm(2) V-1 s(-1), most of which are orders of magnitude higher than those of their corresponding D-A polymers. Notably, the hole mobility of 3.35 cm(2) V-1 s(-1) is among the highest for the quinoidal-aromatic polymers characterized by conventional spin-coating methods. Furthermore, the role of electron acceptors in Q-D-A polymers has been comprehensively investigated. Polymers with stronger acceptor units are more inclined to deliver edge-on lamellas, high film crystallinity, small effective hole masses, and decent operational stability. The detailed structure-property-device performance relationship will pave the way toward high performance semiconducting polymers using the potent Q-D-A strategy.

Automated summary

The quinoid-donor-acceptor (Q-D-A) strategy shows promise in constructing high mobility semiconducting polymers. This study synthesized and characterized new polymers with different electron acceptor units and backbone coplanarity to explore the potential of this strategy. Q-D-A polymers exhibited more planar backbone conformations than their donor-acceptor (D-A) counterparts. Organic field-effect transistors based on Q-D-A polymers demonstrated excellent effective hole mobilities, which were significantly higher than those of D-A polymers. The role of electron acceptors in Q-D-A polymers was comprehensively investigated, revealing increased film crystallinity, smaller effective hole masses, and improved operational stability for polymers with stronger acceptor units. This study provides valuable insights into the structure-property-device performance relationship for high performance semiconducting polymers using the Q-D-A strategy.