▎ 摘　　要

Graphene liquid cells (GLCs) have recently attracted increasing attention in multiple research fields because this technique has provided unique opportunities for studying liquid-phase reactions. Here, we report a simplified approach for the fabrication of GLCs using ultrasonication assistance. We demonstrate that morphologies of fabricated GLCs depend on the number of graphene layers. With the appropriate ultrasound, few-layer graphene assemblies to graphene shells and multilayer graphene (m/G) transforms to graphene scrolls that preserve the liquid pocket inside. We reveal that liquid cells made from mlG offer superior spatial resolution to achieve sub-nanometer detection. More importantly, we investigate the in situ coalescence processes of Au nanoparticles both in the liquid cell and on solid graphene support. From the direct comparison, we show a jump to the contact mode only associated with the coalescence of Au nanoparticles in water. Our study provides a simplified route to prepare GLCs and enhances our understanding of Au nanoparticle's coalescence in different media.