Artificial synapses based on organic electrochemical transistors with self-healing dielectric layers

Organic electrochemical transistors(OECTs)have emerged as one type of promising building block for neuromorphic systems owing to their capability of mimicking the morphology and functions of biological neurons and synapses.Currently,numerous kinds of OECTs have been developed,while self-healing performance has been neglected in most reported OECTs.In this work,the OECTs using self-healing polymer electrolytes as dielectric layers are proposed.Several important synaptic behaviors are simulated in the OECTs by doping the channel layers with ions from the electrolytes.Benefitting from the dynamic hydrogen bonds in the self-healing polymer electrolytes,the OECTs can successfully maintain their electrical performance and the ability of emulating synaptic behaviors after self-healing compared with the initial state.More significantly,the sublinear spatial summation function is demonstrated in the OECTs and their potential in flexible electronics is also validated.These results suggest that our devices are expected to be a vital component in the development of future wearable and bioimplantable neuromorphic systems.

基于CsPbBr_(3)量子点/有机半导体/SnO_(2)异质结的自供电型探测器用于弱光检测

全无机卤化铅钙钛矿量子点由于其优异的光电性能在光电探测器的发展中展示出巨大的潜力.然而,基于纯钙钛矿量子点的光电探测器光响应性能通常受到钙钛矿量子点薄膜电荷传输效率差的限制.本工作报道了基于钙钛矿量子点和有机半导体PQT-12(聚3,3′′′-二十二烷基四噻吩)的高性能自供电光电探测器.即使在自供电模式下,该器件仍然可以对光信号展示出稳定的光响应性质,并实现了优异的光探测性能,包括5.8×10^(12)Jones的探测率和高达105的光暗电流比.更重要的是,器件对于强度低至3 nW cm^(-2)的弱光具有明显的光响应.据我们所知,该器件的自供电弱光探测能力优于大多数报道的基于钙钛矿量子点的光电探测器.此外,器件还可以制备成柔性探测器,在不同的弯曲角度下器件的光电流几乎保持不变.相比于已报道的自供电光电探测器,我们的器件综合性能十分优异.本工作可以为基于钙钛矿量子点开发高性能弱光探测自供电光电探测器提供借鉴.

Retina-Inspired Organic Heterojunction-Based Optoelectronic Synapses for Artificial Visual Systems

For the realization of retina-inspired neuromorphic visual systems which simulate basic functions of human visual systems,optoelectronic synapses capable of combining perceiving,processing,and memorizing in a single device have attracted immense interests.Here,optoelectronic synaptic transistors based on tris(2-phenylpyridine)iridium(Ir(ppy)_(3))and poly(3,3-didodecylquarterthiophene)(PQT-12)heterojunction structure are presented.The organic heterojunction serves as a basis for distinctive synaptic characteristics under different wavelengths of light.Furthermore,synaptic transistor arrays are fabricated to demonstrate their optical perception efficiency and color recognition capability under multiple illuminating conditions.The wavelength-tunability of synaptic behaviors further enables the mimicry of mood-modulated visual learning and memorizing processes of humans.More significantly,the computational dynamics of neurons of synaptic outputs including associated learning and optical logic functions can be successfully demonstrated on the presented devices.This work may locate the stage for future studies on optoelectronic synaptic devices toward the implementation of artificial visual systems.

基于受体修饰的双层有机场效应晶体管化学传感器用于高灵敏检测锂离子电池电解液泄漏

易燃易爆的锂离子电池电解液泄漏是电池故障的早期症状之一,甚至会导致电池自燃或电动汽车爆炸.因此,有必要找到一种快速简单的方法来监测电解液泄漏.现有的传感器难以有效且快速地检测微量电解液泄漏.我们首次提出了一种将有机场效应晶体管(OFET)的灵敏度和联二脲受体的选择性相结合,以检测电池电解液泄漏的策略.复合后的传感器与没有受体的原始传感器相比,灵敏度显著提高,传感器对碳酸二乙酯的检测限低至1.4 ppm.并且可以在几秒钟内有效地检测到微量的泄漏, 200 n L电解液泄漏能够导致3%的响应.受体复合后的OFET传感器的优异性能使其成为锂离子电池安全监测的良好候选者,并为传感技术的发展提供了一个有前途的平台.

Bioinspired organic optoelectronic synaptic transistors based on cellulose nanopaper and natural chlorophyll-a for neuromorphic systems

Inspired by human brains,optoelectronic synapses are expected as one of significant steps for constructing neuromorphic systems.In addition,intensive attention has been paid to biodegradable and biocompatible materials for developing green electronics.In this regard,environmentally friendly organic optoelectronic synaptic transistors based on wood-derived cellulose nanopaper(WCN)as dielectric/substrate and nature chlorophyll-a as photoactive material are demonstrated.Both WCN and chlorophyll-a are biocompatible and biodegradable materials from natural organisms.Versatile synaptic behaviors have been well mimicked by the modulation of both electrical and optical signals.More significantly,optical wireless communication is experimentally emulated and the information processing capability is also verified in pattern recognition simulation.Furthermore,the flexible synaptic transistors exhibit no apparent synaptic performance degradation even when the bending radius is reduced to 1 mm.Our work may develop a promising approach for the development of green and flexible electronics in neuromorphic visual systems.