▎ 摘　　要

NOVELTY - A combustible gas detector (1) comprises a detection electrode (10) containing catalyst having electrochemical oxidation activity and formed on one surface of the graphene oxide composite film, a reference electrode (20) containing platinum or conductive carbon is formed on other surface of the graphene oxide composite film, a potential meter (30) for measuring potential difference between the poles (10, 20), and conductive wire for electrically connecting the poles and potential meter. The graphene oxide composite film is a graphene oxide-sulfonated silk fibroin-cation composite film having sulfonated silk fibroin positioned between nanosheets of graphene oxide having a cation attached to a carboxy group. USE - Combustible gas detector used for detecting combustible gas (claimed) such as hydrogen gas, carbon monoxide and ethanol using graphene oxide. ADVANTAGE - The combustible gas detector does not require additional configuration such as water retention reservoir even under low humidity conditions, and does not dissipate high proton conductivity even at high temperature. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for method for detecting combustible gas using the combustible gas detector. DESCRIPTION OF DRAWING(S) - The drawing shows an outline view of combustible gas detector. (Drawing includes non-English language text) Combustible gas detector (1) Detection electrode (10) Test gas inlet (12) Test gas outlet (14) Detection electrode chamber (16) Reference electrode (20) Control air introduction portion (22) Reference electrode chamber (24) Potential meter (30)