Y6 Organic Thin‐Film Transistors with Electron Mobilities of 2.4 cm 2 V −1 s −1 via Microstructural Tuning

Abstract There is a growing demand to attain organic materials with high electron mobility, μ e , as current reliable reported values are significantly lower than those exhibited by their hole mobility counterparts. Here, it is shown that a well‐known nonfullerene‐acceptor commonly used in organic solar cells, that is, BTP‐4F (aka Y6), enables solution‐processed organic thin‐film transistors (OTFT) with a μ e as high as 2.4 cm 2 V −1 s −1 . This value is comparable to those of state‐of‐the‐art n‐type OTFTs, opening up a plethora of new possibilities for this class of materials in the field of organic electronics. Such efficient charge transport is linked to a readily achievable highly ordered crystalline phase, whose peculiar structural properties are thoroughly discussed. This work proves that structurally ordered nonfullerene acceptors can exhibit intrinsically high mobility and introduces a new approach in the quest of high μ e organic materials, as well as new guidelines for future materials design.