▎ 摘　　要

NOVELTY - A three-electrode system is formed using a reduced-graphene-modified glassy carbon electrode as working electrode, platinum counter electrode, and calomel reference electrode. The system is immersed in palladium chloride and potassium chloride solution, and palladium nanoparticles are deposited on the surface of graphene by potentiostatic method, to obtain reduced graphene-palladium compound. The electrode is washed with deionized water, to obtain a reduced graphene-palladium composite-modified glassy carbon electrode. USE - Preparation of reduced graphene-palladium composite-modified glassy carbon electrode used for detecting nitrite content in phosphate solution (claimed). ADVANTAGE - The method efficiently detects nitrite by obviously observing that nitrite ions are oxidized to nitrates on the surface of graphene palladium composite. DETAILED DESCRIPTION - A three-electrode system type electrolytic cell consisting of a graphite oxide modified glass carbon working electrode, a platinum counter electrode, and a calomel reference electrode is used. The electrode system is immersed in a phosphate solution with a concentration of 0.01-2 mol/dm3 and reduced by cyclic voltammetry after replacing oxygen with nitrogen for 0.5-2 hours, to obtain graphene oxide. The glassy carbon electrode is washed with deionized water several times to obtain reduced-graphene-modified glassy carbon electrode. A three-electrode system is formed using the modified electrode as working electrode, platinum counter electrode, and calomel reference electrode. The system is immersed in 0.001-1 mol/dm3 palladium chloride and 0.5-3 mol/dm3 potassium chloride solution, and palladium nanoparticles are deposited on the surface of graphene by potentiostatic method, to obtain reduced graphene-palladium compound. The electrode is washed with deionized water, to obtain a reduced graphene-palladium composite-modified glassy carbon electrode. An INDEPENDENT CLAIM is included for detection method of nitrite in phosphate solution.