▎ 摘　　要

NOVELTY - Producing reduced graphene oxide comprises (a) preparing a first reactant by dissolving graphite in an acid, adding an oxidizing agent and distilled water to the first reactant, and raising the temperature to react to prepare a second reactant, (b) adding distilled water to the second reactant and adding hydrogen peroxide to react to prepare a third reactant, (c) preparing a dispersion of graphene oxide particles from the supernatant or precipitate formed by centrifuging the third reactant, (d) preparing a fourth reactant by sonicating the dispersion in a first polar solvent, and (e) forming a mixed solution by mixing the fourth reactant and an alcohol solution in which pyrrole is dissolved, sonicating and reacting for a predetermined period of time to reduce. USE - The method is useful for producing reduced graphene oxide and ammonia gas sensor (all claimed) used not only for diagnosis of helicobacter infection and kidney disease, but also for whole industry such as air management in the livestock industry. ADVANTAGE - The method provides high sensitivity to ammonia, excellent portability and ease of use, and economical. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) reduced graphene oxide produced by the above method; (2) ammonia gas sensor comprising reduced graphene oxide by the above method; and (3) producing ammonia sensor, comprising (a), (b), (c), (d), (5) mixing the fourth reactant with an alcohol solution in which pyrrole is dissolved, sonicating and reacting for a predetermined period of time to reduce it to form a mixed solution, filtering the mixed solution, washing with a second polar solvent, followed by drying, dissolving the dried reduced graphene oxide particles in a volatile solvent and distilled water, and (6) developing a thin film on the surface and transferring the thin film to the electrode surface formed on the flexible polymer substrate.