Realizing n Type Field Effect Performance via Introducing Trifluoromethyl Groups into the Donor Acceptor Copolymer Backbone
Developing a new strategy to obtain n type organic semiconductors is crucial for the advance of organic electronics. We herein report the synthesis and investigation of a series of donor acceptor type diazaisoindigo based copolymers, named PAIID TFBVB C1, PAIID TFBVB C3, and PAIID BVB C3. After introduction of the trifluoromethyl groups with strong electron withdrawing ability into the molecular backbone of PAIID BVB C3 containing stilbene units, the obtained polymer PAIID TFBVB C3 shows obvious blue shifted UV vis absorption profiles because of the enlarged band gap revealed by the theoretical simulation. Meanwhile, both the energy levels of the lowest unoccupied molecular orbital (LUMO) of PAIID TFBVB C1 and PAIID TFBVB C3 with trifluoromethyl groups are lower than that of PAIID BVB C3 without trifluoromethyl groups, reducing the energy difference between the LUMO energy level and the work function of the source drain electrode and further facilitating electron injection. Consequently, both the PAIID TF.
Macromolecules