▎ 摘　　要

NOVELTY - Preparation of graphene quantum dots involves carbonizing sea rice, dispersing in alkali solution, oxidizing with hydrogen peroxide, adjusting pH to neutrality, filtering, and dialyzing. USE - Preparation of graphene quantum dots used as fluorescent (closed) probe for quantitatively detecting 4-nitro phenol optical sensor based on fluorescence internal filtration effect (IFE) (all claimed) in environment detection, and cancer diagnosis and treatment. ADVANTAGE - The graphene quantum dots have good temperature sensitivity and potential application value in the field of temperature-related fluorescence sensing, and used as fluorescent probes to detect 4-nitro phenol has characteristics of low detection limit, wide detection range, excellent stability and selectivity and excellent anti-interference performance. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for detecting p-nitro phenol, which involves adding the graphene quantum dots in sample to be tested, leaving still after shaking, testing the photoluminescence spectrum of above-mentioned solution under the excitation light of 340 nm, and calculating the concentration of p-nitro phenol in sample to be tested.