Donor‐Glycolated Quinoidal Polymers Enable Fast N‐Type Organic Electrochemical Transistors

ABSTRACT

Fast, stable n‐type organic mixed ionic‐electronic conductors remain scarce. We report a donor glycolated, quinoidal design that facilitates efficient n‐doping and spatially separates hydrophilic side chains from n‐doping sites to preserve electronic pathways. The resulting polymer PQ‐gT, synthesized from a glycolated bithiophene donor and a quinoidal bifuran‐dione acceptor, exhibits high mixed conduction with a figure of merit of µC * = 10.9 F cm ⁻¹ V ⁻¹ s ⁻¹ . In planar accumulation‐mode organic electrochemical transistors (OECTs), it exhibits nearly symmetric sub‐millisecond transients with switching on‐ and off‐times of τ _on / τ _off = 0.5/0.2 ms. These values represent the fastest operation for this type of device architecture. Partial donor replacement with dialkoxybithiazole tunes packing and suppresses swelling, raising µC * to 21.5 F cm ⁻¹ V ⁻¹ s ⁻¹ at 25% substitution, albeit with slower switching. In vertical OECTs, PQ‐gT supports balanced ambipolar operation with ∼1 ms switching and enables a single‐material complementary inverter (gain ≈ 40 V V ⁻¹ at V _IN < 100 mV) that is stable over 10 000 cycles and functional up to 200 Hz. This donor‐glycolated quinoidal strategy furnishes intrinsically fast, aqueous‐stable n‐type organic mixed ionic‐electronic conductors for bioelectronic circuits.