MoS<sub>2</sub> Quantum Dot-Optimized Conductive Channels for a Conjugated Polymer-Based Synaptic Memristor
Qiongshan Zhang, Qizhi Jiang, Fei Fan, Gang Liu, Yu Chen, Bin Zhang
Abstract
Donor–acceptor-type conjugated polymers are widely used in memristors due to their unique push–pull electron structures and charge transfer mechanisms. However, the inherently inhomogeneous microstructure of polymer films and their low crystallinity produce randomness that destabilizes formed conductive channels, giving polymer-based memristors unstable switching behavior. In this contribution, we prepared a synaptic device based on PM6–MoS 2 QD (molybdenum disulfide quantum dot) nanocomposites. In the composites, MoS 2 QDs provided the active centers for forming conductive channels via electron trapping and detrapping. They also controlled the directional formation of conductive channels between PM6 and MoS 2 QDs, reducing randomness and giving devices a narrow switching voltage range and cycling longevity. The device exhibited continuous multistage conductance states under a direct current voltage sweep and simulated a variety of synaptic functions, including long-term potentiation, long-term depression, short-term potentiation, short-term depression, paired-pulse facilitation, spiking-rate-dependent plasticity, and “learning experience” behavior. The memristor could also perform arithmetic, including “counting” and “subtraction” operations. This work provides a new approach to improving the performance of memristors for neuromorphic computing.