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Abstract Organic electrochemical transistors (OECTs) hold promise for developing a variety of high‐performance (bio‐)electronic devices/circuits. While OECTs based on p‐type semiconductors have achieved tremendous progress in recent years, n‐type OECTs still suffer from low performance, hampering the development of power‐efficient electronics. Here, it is demonstrated that fine‐tuning the molecular weight of the rigid, ladder‐type n‐type polymer poly(benzimidazobenzophenanthroline) (BBL) by only one order of magnitude (from 4.9 to 51 kDa) enables the development of n‐type OECTs with record‐high geometry‐normalized transconductance (gm,norm ≈ 11 S cm−1) and electron mobility × volumetric capacitance (µC* ≈ 26 F cm−1 V−1s−1), fast temporal response (0.38 ms), and low threshold voltage (0.15 V). This enhancement in OECT performance is ascribed to a more efficient intermolecular charge transport in high‐molecular‐weight BBL than in the low‐molecular‐weight counterpart. OECT‐based complementary inverters are also demonstrated with record‐high voltage gains of up to 100 V V−1and ultralow power consumption down to 0.32 nW, depending on the supply voltage. These devices are among the best sub‐1 V complementary inverters reported to date. These findings demonstrate the importance of molecular weight in optimizing the OECT performance of rigid organic mixed ionic–electronic conductors and open for a new generation of power‐efficient organic (bio‐)electronic devices.
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A hybrid transistor with transcriptionally controlled computation and plasticity
Abstract Organic electrochemical transistors (OECTs) are ideal devices for translating biological signals into electrical readouts and have applications in bioelectronics, biosensing, and neuromorphic computing. Despite their potential, developing programmable and modular methods for living systems to interface with OECTs has proven challenging. Here we describe hybrid OECTs containing the model electroactive bacteriumShewanella oneidensisthat enable the transduction of biological computations to electrical responses. Specifically, we fabricated planar p-type OECTs and demonstrated that channel de-doping is driven by extracellular electron transfer (EET) fromS. oneidensis. Leveraging this mechanistic understanding and our ability to control EET flux via transcriptional regulation, we used plasmid-based Boolean logic gates to translate biological computation into current changes within the OECT. Finally, we demonstrated EET-driven changes to OECT synaptic plasticity. This work enables fundamental EET studies and OECT-based biosensing and biocomputing systems with genetically controllable and modular design elements.
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- PAR ID:
- 10491913
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 15
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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