Silk fibroin/graphene quantum dots composite memristor with multi-level resistive switching for synaptic emulators

Memristors with multi-level resistive switching have gained growing interest for information storage and applications in synaptic emulators. In this work, we fabricated silk fibroin (SF)/graphene quantum dots (GQD) composite memristors with good stability and a large switching window using a layer-by-layer method. Non-volatile binary and ternary switching behaviors were realized by regulating the interface interaction between SF and GQDs. The GQD/SF/GQD-based memristor displays three resistance states in a single scanning cycle with good repeatability, which is different from traditional binary switching of the GQD/SF-based memristor and results from an interface barrier in the device. This ternary switching behavior is dominated by the Schottky emission mechanism. In addition, benefiting from the excellent memristive properties of the GQD/SF/GQD-based memristor, the basic functions of synapses such as non-linear transmission property and paired pulse facilitation effect can be simulated, suggesting its potential applications in synaptic emulators and other bioelectronics.