Mass transport behavir of electrochemical species through plasma-poylerized thin film on platinum electrode

摘要

We propose a novel method or generating thin film coating for use on a platinum(Pt)electrode. This is accomplished y a plasma-polymerized film(PPE), which is deposited directly oto the substrate under dry condition. The resulting films are exte3emely t in(<100nm), have good adherence to the substrate(electrode, and have a highly-cross-liked netowrk structure. The PPF-deposited Pt electrode shows a high selectivity towqards targeted species without decreasing the sensivity (i.e.maintaning a high electrical signal). This property is rpartly atrributed to size discrimination from a highly-cross-linked network structure in the film. Moreover, an acetonitrile PPF-deposited Pt electrode showed accumulation ability for hydrogen peroxide detection; the sensitivity of the PPF-deposited electrode(30-59 nm of film thickness)is one and half times larger than that of bare electrode. Chronocoulojetric data support this effect. A hexadiene PPF-deposited Pt leectrode also showed high selectivity between dopamine and ascoric acid compared with a bare Pt electrode; the selectivity ratio for PPF-depsited electrode(37 nm or film thickness)is 12, whereas that of the bare electrode is 4.6. We demonstrate and siscuss mass transport behavior of electrochemical species through plasma-polymerized thin film on platinum electrode.