Zachary S. Parr1, Reem B. Rashid2, Bryan D. Paulsen2, Benjamin Poggi1, Ellasia Tan1, Mark Freeley1, Matteo Palma1, Isaac Abrahams1, Jonathan Rivnay2, Christian B. Nielsen1
1Materials Research Institute and School of Biological and Chemical, Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, UK
2Department of Biomedical Engineering, Northwestern University, Evanston, IL, 60202 USA
Tóm tắt
AbstractA series of semiconducting small molecules with bithiophene or bis‐3,4‐ethylenedioxythiophene cores are designed and synthesized. The molecules display stable reversible oxidation in solution and can be reversibly oxidized in the solid state with aqueous electrolyte when functionalized with polar triethylene glycol side chains. Evidence of promising ion injection properties observed with cyclic voltammetry is complemented by strong electrochromism probed by spectroelectrochemistry. Blending these molecules with high molecular weight polyethylene oxide (PEO) is found to improve both ion injection and thin film stability. The molecules and their corresponding PEO blends are investigated as active layers in organic electrochemical transistors (OECTs). For the most promising molecule:polymer blend (P4E4:PEO), p‐type accumulation mode OECTs with µA drain currents, μS peak transconductances, and a µC* figure‐of‐merit value of 0.81 F V−1 cm−1 s−1 are obtained.
