Controlled Dedoping and Redoping of N-Doped Poly(benzodifurandione) (n-PBDF)

Abstract

The doping levels of conjugated polymers significantly influence their conductivity, energetics, and optical properties. Recently, a highly conductive n-doped polymer called poly (3,7-dihydrobenzo[1,2-b:4,5-b′]difuran-2,6-dione) (poly(benzodifurandione), n-PBDF) is discovered, opening new possibilities for n-type conducting polymers in printed electronics and other fields. Controlling the doping level of n-PBDF is of great interest due to its wide range of potential applications. Here controlled dedoping and redoping of n-PBDF is reported and a mechanistic understating of such a process is provided. Dedoping occurs through electron transfer and proton capture, wherein the ionic dopants, tris(4-bromophenyl)ammoniumyl hexachloroantimonate (Magic Blue), exhibit efficient proton capture ability and stronger interaction with n-PBDF, resulting in high dedoping efficiency. Moreover, chemically dedoped PBDF can be redoped using various proton-coupled electron transfer agents. By manipulating the doping levels of n-PBDF thin films, ranging from highly doped to dedoped states, the system demonstrates controllable conductivity in five orders of magnitude, adjustable optical properties, and energetics. As a result, these characteristics demonstrate the potential applications of n-PBDF in organic electrochemical transistors and thermoelectrics.