Organic mixed conductors have garnered significant attention in applications from bioelectronics to energy storage/generation. Their implementation in organic transistors has led to enhanced biosensing, neuromorphic function, and specialized circuits. While a narrow class of conducting polymers continues to excel in these new applications, materials design efforts have accelerated as researchers target new functionality, processability, and improved performance/stability. Materials for organic electrochemical transistors (OECTs) require both efficient electronic transport and facile ion injection in order to sustain high capacity. In this work, we show that the product of the electronic mobility and volumetric charge storage capacity (µC*) is the materials/system figure of merit; we use this framework to benchmark and compare the steady-state OECT performance of ten previously reported materials. This product can be independently verified and decoupled to guide materials design and processing. OECTs can therefore be used as a tool for understanding and designing new organic mixed conductors.
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: We are thankful to the following chemists for providing materials and support: Alexander Giovannitti and Iain McCulloch (Imperial/KAUST) for p(g2T-TT), p(g2T-T), p(gBDT-g2T), and p(gNDI-g2T); Mukundan Thelakkat (Bayreuth) for PTHS; Gordon Wallace and Paul Molino (Wollongong) for PEDOT:DS; and George Hadziioannou (Bordeaux) for PEDOT:PSTFSI and PEDOT:PMATFSI. The authors would like to thank Ilke Uguz and Mary Donahue for their assistance in device fabrication.