Self-Assembled Monolayer and Nanoparticles Coenhanced Fragmented Silver Nanowire Network Memristor

Abstract

Silver nanowire (AgNW) networks with self-assembled structures and synaptic connectivity have been recently reported for constructing neuromorphic memristors. However, resistive switching at the cross-point junctions of the network is unstable due to locally enhanced Joule heating and the Gibbs−Thomson effect, which poses an obstacle to the integration of threshold switching and memory function in the same AgNW memristor. Here, fragmented AgNW networks combined with Ag nanoparticles (AgNPs) and mercapto self-assembled monolayers (SAMs) are devised to construct memristors with stable threshold switching and memory behavior. In the above design, the planar gaps between NW segments are for resistive switching, the AgNPs act as metal islands in the gaps to reduce threshold voltage (V th ) and holding voltage (V hold ), and the SAMs suppress surface atom diffusion to avoid Oswald ripening of the AgNPs, which improves switching stability. The fragmented NW-NP/SAM memristors not only circumvent the side effects of conventional NW-stacked junctions to provide durable threshold switching at >V th but also exhibit synaptic characteristics such as long-term potentiation at ultralow voltage (≪V th ). The combination of NW segments, nanoparticles, and SAMs blazes a new trail for integrating artificial neurons and synapses in AgNW network memristors.

Kinetically Controlled Self-Assembly of Ag Nanoclusters with Enhanced Luminescence

“…Self-assembly affords routes for spontaneously organizing diverse functional nanomaterials into highly ordered superstructures with controllable size and shape by reconstructing the balance between thermodynamic forces and various nanoscale molecular forces. − Through regulating the connection fashion and manipulating the spatial distribution of nanomaterials, self-assembly not only enriches the structural complexity and functional maximization but also influences the atomic and electronic structure and energy and charge transfer, affording and optimizing the unique optical, electrical, physical, and chemical properties that are beyond those of the individual building blocks. − In the past decades, self-assembly structural and performance explorations on various nanomaterials such as organic molecules, large nanoparticles (NPs) (>3 nm), peptide, and DNA have been performed and great achievements have been obtained. With metal NCs as the new-emerged nanomaterials with many unique advantages, fabricating highly ordered metal NC self-assembly structures would be hopeful for largely improving their PL performance and enriching other diverse properties. , However, the research on metal NC self-assembly still progresses slowly and presents significant challenges.…”