A high-conductivity n-type polymeric ink for printed electronics

Abstract

Abstract Conducting polymers, such as the p -doped poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS), have enabled the development of an array of opto- and bio-electronics devices. However, to make these technologies truly pervasive, stable and easily processable, n -doped conducting polymers are also needed. Despite major efforts, no n -type equivalents to the benchmark PEDOT:PSS exist to date. Here, we report on the development of poly(benzimidazobenzophenanthroline):poly(ethyleneimine) (BBL:PEI) as an ethanol-based n -type conductive ink. BBL:PEI thin films yield an n -type electrical conductivity reaching 8 S cm −1 , along with excellent thermal, ambient, and solvent stability. This printable n -type mixed ion-electron conductor has several technological implications for realizing high-performance organic electronic devices, as demonstrated for organic thermoelectric generators with record high power output and n -type organic electrochemical transistors with a unique depletion mode of operation. BBL:PEI inks hold promise for the development of next-generation bioelectronics and wearable devices, in particular targeting novel functionality, efficiency, and power performance.