Fig. 1: Doped electron transporting organic electrochemical transistors.
a Materials used throughout this work: a copolymer made from naphthalene-1,4,5,8-tetracarboxylic diimide (NDI) and bithiophene (T2) with ethylene glycol or alkyl side chains attached to the NDI unit the comonomer, named P-90; the Lewis basic ammonium salt tetra-n-butylammonium fluoride (TBAF) used as an n-dopant. b Transconductance of best-performing P-90 organic electrochemical transistors containing 0, 10, 40 and 80 molar percentage (mol%) TBAF. gm_max is taken at VG ≈ 0.5 V and VD ≈ 0.6 V, all transistors have a channel length and width of 10 µm and 100 µm, respectively, and channel thicknesses are given in Table 1. c Cyclic voltammetry measurements for P-90 thin-films containing 0, 10, 40 and 80 mol% TBAF, measured at a scan rate of 0.05 V/s, with labelled redox peaks. Film thicknesses are given in Table 1. d Organic electrochemical transistor configuration and graphical illustration representing TBAF doping mechanisms in P-90, which increase electron density and subsequent ion uptake.
