Combined nanoarchitectonics with self-assembly and electrosynthesis for flexible PTCDIs@PEDOT films with interpenetrating P–N heterojunctions

Abstract

A novel synthesis method for fabricating large area, uniform bulk-heterojunction films with electron donor and acceptor materials homogeneously distributed among each other forming a bicontinuous network morphology is reported. The acceptor part was fabricated as nanofibers self-assembled from perylene tetracarboxylic diimide (PTCDI) molecules, which form a typical n-type semiconductor. The donor part was a classic P-type conducting polymer, poly(3,4-ethylenedioxythiophene) (PEDOT), which can be electrochemically polymerized from the EDOT monomer directly inside the nanofiber mesh, forming an interpenetrating P–N network. The nanofiber-based P–N heterojunction film demonstrates significant photocurrent generation. The facile and universal fabrication process combining in situ electrochemical polymerization with molecular self-assembly may find broader application in materials fabrication and structural engineering for P–N heterojunctions in photovoltaics and other optoelectronics.