▎ 摘　　要

NOVELTY - A porous metal oxide-catalyzed double porous structure comprises an electrode containing transition metal, a porous indium oxide catalyst layer coated with palladium deposited on the electrode, and graphene balls coated with a graphene ball-metal catalyst structure stacked on the catalyst layer. The graphene balls are nanoparticles. USE - Porous metal oxide graphene ball-catalyst structure for detecting ethylene by a sensor (claimed). ADVANTAGE - The ethylene detection laminate has high selective sensitivity, reduces sensor sensitivity of hydrogen, carbon monoxide, ethanol, and ammonia gas, and increases ethylene gas sensitivity, and minimizes problem of food waste by easily detecting freshness of perishable fruits and vegetables. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: a sensor; and a method for detecting ethylene by a sensor. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic representation of the porous metal oxide graphene ball-catalyst structure (Drawing includes non-English language text).