Electrical Current Modulation in Wood Electrochemical Transistor

The nature of mass transport in plants has recently inspired the development of low-cost and sustainable wood-based electronics. Herein, we report a wood electrochemical transistor (WECT) where all three electrodes are fully made of conductive wood. The conductive wood is prepared using a two-step strategy of wood delignification followed by wood amalgamation with a mixed electron-ion conducting polymer, poly(3,4-ethylenedioxythiophene)polystyrene sulfonate (PEDOT:PSS). The modified wood has an electrical conductivity of up to 69 Sm-1 induced by the formation of PEDOT:PSS microstructures inside the wood 3D scaffold. Conductive wood is then used to fabricate the WECT, which is capable of modulating an electrical current in a porous and thick transistor channel (1 mm) with an on/off ratio of 50. The device shows a good response to gate voltage modulation and exhibits dynamic switching properties similar to those of an organic electrochemical transistor (OECT). This wood-based device and the proposed working principle demonstrate the possibility to incorporate active electronic functionality into the wood, suggesting different types of bio-based electronic devices植物体内的物质输运特性近期启发了低成本、可持续木质电子器件的研发。本文报道了一种木质电化学晶体管（wood electrochemical transistor, WECT），其全部三个电极均由导电木材制备而成。该导电木材采用两步法制备：先对木材进行脱木质素处理，随后将其与电子-离子混合导电聚合物聚(3,4-乙烯二氧噻吩)-聚苯乙烯磺酸盐（PEDOT:PSS）复合。得益于木材三维骨架内部形成的PEDOT:PSS微观结构，改性后的木材电导率最高可达69 S·m⁻¹。随后利用该导电木材制备得到WECT，该器件可对厚度达1 mm的多孔厚晶体管沟道中的电流进行调控，开关比达50。该器件对栅极电压调制表现出良好响应，其动态开关特性与有机电化学晶体管（organic electrochemical transistor, OECT）相似。该木质器件及其所提出的工作原理证实了将有源电子功能集成至木材中的可行性，为开发不同类型的生物基电子器件提供了新的可能。