One-step electrochemically induced fabrication of amine carbon quantum dots: Efficient catalyst for Knoevenagel condensation at ambient conditions

Abstract

This study presents a straightforward electrochemical method to prepare Diethylenetriamine Carbon Quantum Dots (DETA-CQDs) at room temperature and atmospheric pressure. The CQDs were synthesized using diethylenetriamine as the sole precursor in an alkaline medium. In order to streamline purification, we employed a solvent precipitation technique. Comprehensive characterization using HR-TEM, XPS, IR, Raman, UV-visible spectroscopy and photoluminescence confirmed their structural and optical properties. The catalytic potential of DETA-CQDs was demonstrated in a model Knoevenagel condensation reaction, where it functioned as Bronsted base catalyst. Notably, the catalyst remained effective for two reuse cycles. The exceptional catalytic activity is attributed to the amine-rich surface, small size, and excellent water dispersibility of the CQDs. The reaction catalyzed by DETA-CQDs was seen to proceed within a minute at room temperature with a good yield of 79 percent. This study highlights the efficacy of electrochemical synthesis in producing amine carbon dots with enhanced functional properties. Furthermore, our results establish DETA-CQDs as a highly efficient and reusable base catalyst, outperforming previously reported materials in Knoevenagel reactions.