Synthesis of graphene quantum dots from diesel fractions and the application in electrochemiluminescence detection of copper ions

To achieve high value-added utilization of diesel fractions, this study employs chemical vapor deposition (CVD) technology, utilizing industrial waste diesel fractions as a carbon source, to deposit carbon films on nickel substrates. Subsequently, graphene quantum dots (GQDs) are synthesized via electrochemical exfoliation, and their application in copper ion detection is explored. The GQDs prepared through this method exhibit uniform size and excellent fluorescence properties. Additionally, this method combines the advantages of CVD in growing high-quality carbon films with the green and controllable characteristics of electrochemical exfoliation, achieving efficient synthesis with minimal environmental impact. This provides a novel green solution for the high-value utilization of diesel fractions. The obtained GQDs were characterized using ultraviolet-visible spectroscopy (UV–Vis), photoluminescence (PL) spectroscopy, and transmission electron microscopy (TEM), demonstrating excellent optical properties and stable fluorescence response. A paper-based electrochemical luminescence (ECL) sensor using GQDs as the substrate and K₂S₂O₈ as the co-reagent was developed for Cu²⁺ detection. The sensor exhibits a detection range of 0.01–1000 μM. Experimental results confirm that the ECL response undergoes significant changes with increasing Cu²⁺ concentration, enabling effective detection. This study not only demonstrates an innovative recycling pathway for diesel component waste as a carbon precursor for GQDs but also provides a sensitive and selective ECL sensing platform for copper ion detection and bioanalytical applications.