Two-dimensional transition metal dichalcogenides are highly promising platforms for memristive switching devices that seamlessly integrate computation and memory. Grain boundaries (GBs), an important micro-nanoscale structure, hold tremendous potential in memristors, but their role remains unclear due to their random distribution, which hinders fabrication. Herein, we present a novel chemical vapor deposition approach to synthesize star-shaped MoS2 nanoflakes with precisely positioned GBs. This approach enables memristor fabrication at specific locations and notably reduces the average set voltage (16-fold reduction) compared to single-crystalline MoS2, due to reduced diffusion barriers for metallic ions through GBs, as further validated by theoretical calculations. These findings offer a new method for synthesizing TMDs with controlled GBs for memristor fabrication, highlighting the crucial role of GBs in reducing set voltage and power consumption, advancing memristive switching devices toward applications in integrated computation and memory systems.
Keywords: chemical vapor deposition (CVD); controllable synthesis strategy; grain boundaries (GBs); memristors; transition metal dichalcogenides (TMDs).