Pyrolytic Lignin: A Promising Precursor for the Green Synthesis of Fluorescent Carbon Nanoparticles

This study presents a simple and cost-effective approach for synthesizing pyrolytic lignin-based carbon dots (CDPLs) via controlled thermal pyrolysis in water. To the best of our knowledge, this is the first time that pyrolytic lignin has been used as a precursor for carbon dots. The one-pot method produced blue/green fluorescent CDPLs with an average size of 34 nm and a negative surface charge of -10.4 mV. The characterization techniques revealed the optical properties and chemical composition of CDPLs, with a fluorescence quantum yield of 7.9%, which is comparable to those of lignin-derived carbon dots. The decay lifetime of CDPLs was in the nanosecond range, which is typical for carbon dots. This study demonstrates the potential of using pyrolytic lignin, a lignocellulosic byproduct, to produce carbon dots through a simple and reproducible method, contributing to the development of sustainable carbon-based nanomaterials.