Dioxoindoloindol-ylidene-malononitrile and benzodifurandione connected organic semiconductors for n-type unencapsulated field-effect transistors

Two organic semiconductors with dioxoindoloindol-ylidene-malononitrile and benzodifurandione were synthesized. These semiconductors integrated strong electron-deficient lactam, lactone, and cyano groups within their conjugated backbones and were applied to n-type unencapsulated organic field-effect transistors (OFETs). Organic semiconductors demonstrated fully co-planar structures and low-lying unoccupied molecular orbital energy levels (−4.32 eV). OFET devices evaluated without encapsulation under ambient conditions exhibited unipolar electron transport characteristics with a peak electron mobility of 3.90 × 10⁻³ cm²V^–1s^–1.