title: Effect of pre-treatment on the surface and electrochemical properties of screen-printed carbon paste electrodes.
abstract: The effect of various electrochemical pre-treatment methods on the surface and electrochemical properties of screen-printed carbon paste electrodes (SPCE) prepared with three different commercial products was examined. It was observed that a positively charged redox couple, e.g., hexaammineruthenium(III), exhibited quasi-reversible behavior at the untreated SPCE. However, the cyclic voltammograms (CVs) of the SPCE prepared with general-purpose carbon inks did not exhibit clear redox peaks to other representative redox couples [e.g., hexacyanoferrate(III), hexachloroiridate(IV), dopamine, and hydroquinone] without activation. Electrochemical pre-treatment methods were sought in four different aqueous solutions, i.e., sulfuric acid, potassium chloride, sodium hydrogencarbonate, and sodium carbonate, applying various activation potentials. It was found that the pre-treatment procedure in saturated Na2CO3 solution at 1.2 V provides a mild and effective condition for activating the SPCE. By measuring the water contact angles at the SPCE surfaces and recording their SEM images, it was confirmed that the electrochemical pre-treatment effectively removes the organic binders from the surface carbon particles. A prolonged period of activation (> 5 min) or the use of high potentials (> 1.2 V) increased the capacitance of the electrode over 20 microF cm(-2). The pre-treated SPCE behaved like a random array microelectrode, exhibiting a sigmoidal-shaped CV at a slow scan rate. The short pre-anodization method in Na2CO3 solution was generally applicable to most SPCE prepared with general-purpose carbon inks.
authors.affiliation: Chemical Sensor Research Group, Department of Chemistry, Kangwon University, Seoul, Korea.
authors.forename: G
authors.initials: G
authors.lastname: Cui
authors.forename: J H
authors.initials: JH
authors.lastname: Yoo
authors.forename: J S
authors.initials: JS
authors.lastname: Lee
authors.forename: J
authors.initials: J
authors.lastname: Yoo
authors.forename: J H
authors.initials: JH
authors.lastname: Uhm
authors.forename: G S
authors.initials: GS
authors.lastname: Cha
authors.forename: H
authors.initials: H
authors.lastname: Nam