High-Performance, Single-Component Ambipolar Organic Electrochemical Transistors with Balanced n/p-Type Properties for Inverter and Biosensor Applications

Ambipolar organic electrochemical transistors (OECTs) with a single organic mixed ionic-electronic conductor (OMIEC) have unique advantages by reducing fabrication complexity and cost in complementary logic circuit and bioelectronic applications. However, the design and synthesis of high-performance ambipolar OMIECs for efficient transport and coupling both cation/anion and electron/hole remain challenging. Herein, a donor–acceptor (D–A)-typed ambipolar OMIEC polymer (DHF-gTT) is presented, whose superior ambipolarity stems from the concurrent oligoethyleneglycol-functionalized D/A units that facilitates cation/anion injection and transport. Additionally, the fluorination of acceptor unit improves both hole/electron transports due to the fully-locked backbone and promotes electron injection by down-shifting molecular energy levels. Consequently, DHF-gTT-based OECTs achieve balanced figure-of-merit (µC^*) for both p-type and n-type operations (12.4–14.6 F cm⁻¹ V⁻¹ s⁻¹), setting new benchmarks for ambipolar OECTs, in terms of n-type µC^* and electron/hole mobilities. Such ambipolar OECTs enable the inverter to achieve a record-high gain (102 V/V) and associated n-type and p-type molecular detectors to offer real-time and highly sensitive detection of histamine and hydrogen peroxide detection, respectively. These results indicate the effectiveness of judicious molecular design on achieving high-performance ambipolar OMIECs, allowing the state-of-the-art single-component ambipolar OECTs for both highly integrated logic circuit and bioelectronic applications.