Structural transition of gold octahedrons to nanoprisms induced by nitrogen-doped carbon quantum dots

Colloidal novel metallic nanoparticles have drawn much attention due to their localized surface plasmon resonance (LSPR) effects. It is important to produced homogeneously morphological features in sizes and shapes to quantify the analytes of interest through LSPR properties. Here, we demonstrated a simple synthetic strategies to produce Au nanoprisms by adding nitrogen-doped carbon quantum dots (NCQDs) as a co-capping agent. The NCQDs were prepared via graphitization by selecting citric acid as a carbon source and either urea or polyethyleneimine (PEI) as a nitrogen source. In the presence of NCQDs, the formation of Au nanoprisms can be achieved with approximately 2 μm of edge length when the PEI-derivative NCQDs. The mechanism of Au nanoprism formation were investigated by electron microscopy techniques to investigate the effect of NCQDs on the formation of Au crystals.