▎ 摘　　要

NOVELTY - Preparing lignin-based graphene quantum dot material involves dissolving acid medium or alkaline medium and an oxidant in deionized water, heating it at 60-80 degrees C, and stirring well. Alkali lignin is added and incubated at 60-80 degrees C. The obtained solution is filtered with water-based filter membrane, filtrate is collected, hydrazine hydrate is added to filtrate, sealed and sonicated, and hydrothermal reaction is performed at 180-200 degrees C. The filtrate is collected by using water-based filter membrane, and filtrate is placed in retained dialysis bag, dialyzed in deionized water, and freeze-dried. USE - The method enables to prepare lignin-based graphene quantum dot material for use in the fields of anti-counterfeiting, biological imaging, optoelectronic devices, highly sensitive sensing, or catalysis (claimed) and that can be applied to the field of food and drug security. ADVANTAGE - The method does not need to rely on a high-temperature thermal cracking process, has simple operation and low cost, has a perfect oxidation system, and good oxidizing ability. The lignin-based graphene quantum dots have good biocompatibility, low biological toxicity, and excellent photoluminescence performance.