▎ 摘　　要

NOVELTY - Preparation of graphite pencil-modified electrode involves ultrasonically dispersing graphene oxide in a perfluorinated resin solution, immersing graphite pencil electrode in obtained graphene oxide suspension, and performing electrochemical polymerization using cyclic voltammetry. USE - Preparation of graphite pencil-modified electrode used for detecting dihydroxybenzene isomer in water (claimed). ADVANTAGE - The method enables economical preparation of graphite pencil-modified electrode with high sensitivity and detection limit. The graphite pencil-modified electrode simultaneously detects three phenolic substances. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for detection of dihydroxybenzene isomer in water, which involves immersing the graphite pencil-modified electrode in 0.2 mol/L disodium hydrogen phosphate solution or 0.1 mol/L sodium hydroxide solution, scanning 30-60 cycles using cyclic voltammetry, testing open circuit potential in an electrochemical workstation, immersing the treated electrode in a phenolic compound solution, and detecting the content of phenolic compound in the phenolic compound solution by a differential pulse voltammetry.