Fabrication of fluorescent carbon dots by laser ablation in alkaline solution coupled with Ag nanoparticles for enhanced SERS

Abstract

In this work, SERS enhancement is realized by plasmon coupling and fluorescence resonance energy transfer (FRET) processes concerning to fluorescent carbon dots (CDs) coupled with silver nanoparticles (Ag-NPs). Laser ablation in alkaline solution is a promising strategy to synthesize well-dispersed CDs with sizes below 10\xa0nm by simultaneously creating defect states and oxygen-related functional groups. SERS studies indicated that an amplified signal can be recorded for the hybrid substrate composed by CDs and Ag-NPs. The optimized hybrid substrate comprised of CDs and cubic Ag-NPs has a SERS detection limit of 10−8\xa0M for 4-ATP, indicating the potential applications for trace detection.