Green synthesis of carbon dots from cordyceps militaris and versatile applications in alcohol detection and waterproof fluorescent ink

Carbon dots (CDs) are a class of highly efficient and low-toxicity fluorescent nanomaterials. In this study, using cordyceps militaris as a carbon source, we prepared green-emitting CDs with excellent properties, such as good photobleaching resistance, salt resistance and chemical stability, as well as high quantum yield. Further exploration of the versatile applications of G-CDs in chemical detection and information anti-counterfeiting fields revealed that G-CDs can not only be used as detection agent for analyzing alcohol content in alcoholic beverages but also serve as waterproof fluorescent ink for painting and writing due to their water-resistant property. This work is based on natural biomass as the main precursor to prepare fluorescent CDs with excellent luminescent characteristics and stable physicochemical properties. It is significant for reducing reliance on chemical reagents, lowering the cost of synthesizing CDs, and expanding the application range of CDs.