▎ 摘　　要

NOVELTY - Mixed film of reduced graphene oxide (rGO) and carbon nanotubes (CNT) has a film density of 1.1-1.3 g/cm3, where the ratio of oxygen atoms to carbon atoms (O/C) as determined by X-ray photoelectron spectrometry is less than 0.3. USE - The mixed film is useful in a capacitor (claimed), preferably as electrode of electrochemical capacitor, such as pseudocapacitor. ADVANTAGE - The mixed film has less turning and blending ratio and electrical resistance. The capacitor has low film density and electric resistance as electrode having large specific capacity. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) a capacitor using the mixed film of reduced graphene oxide and carbon nanotubes as electrode; and (2) a method for producing the mixed film, involving uniformly mixing aqueous solution of graphene oxide with aqueous solution of carbon nanotubes, adding ammonia to obtained mixed liquid, heating the mixed liquid, and performing reduction treatment using hydrazine, preparing mixed film by filtering the mixed liquid after completing reduction treatment, and performing vacuum drying treatment and heat treatment.