An Investigation on the transport properties of spin coated redox-active nafion® thin films using cyclic voltammetry

Redox-active hexaammineruthenium(III) [Ru(NH3)6]3+ incorporated Nafion® thin films (\u3c600 \u3enm) were fabricated using spin-coating technique on indium tin oxide (ITO) coated glass substrate. The deposition of the films onto the substrates was verified using energy dispersive x-ray (EDX), surface morphology characterized using scanning electron microscopy (SEM), and electrochemical characteristic through cyclic voltammetry. The concentration of the ruthenium complex, and thinning rate were chosen as the parameters for the study. EDX results confirm the presence of the films on the substrate. Surface morphological results determine that the film is smooth at 10,000x magnification but exhibit lumps at high concentrations but were smoothened out at increasing thinning rates. Voltammetry results show that peak currents decrease at increasing thinning rates and at decreasing concentrations. Moreover, the diffusion coefficients decrease at increasing concentration and decrease at increasing thinning rates. Calculated values of the diffusion coefficients indicate that the ruthenium complex is immobilized in the film

Physical and electrochemical analyses of spin coated hexaammineruthenium(III)/ Nafion/ITO electrodes for heavy metal detection

Varying concentrations of hexaammineruthenium (III), [Ru(NH3)6]3+- Nafion®, films were spin coated on indium tin oxide (ITO)-coated glass substrates. The coating solutions were diluted with ethanol, methanol, or isopropanol. The effects of the solvent type, [Ru(NH3)6]3+ or RuHex concentration, and spin rate on the morphology and transport properties of the fabrication electrodes were investigated. Surface micrographs revealed the presence of sub-micron grooves that diminished with increased RuHex concentration. The surface morphology of the electrodes, however, was independent of the spin rate. The viscosity, η, for all 3 solvent types has an inverse power, n = -0.5, proportionality with RuHex concentration, x i.e. {u1D702}={u1D45A}{u1D465}−0.5. Isopropanol diluted solutions were more viscous than ethanol and methanol diluted solutions with the latter being the least viscous. 75mgRuHex/30mL concentrations were prone to become semi-solid gel suspensions. Cyclic voltammetry determined that 50mgRuHex/30mL, isopropanol-diluted solution, spin coated at 2000rpm yielded the best electrode. The optimized electrodes were used to detect lead and cadmium in yellow and pink pigments obtained from commercially available water colors and mask paint

Fabrication and electrochemical study of [Ru(NH3)6]\u3csup\u3e3+\u3c/sup\u3e/Nafion modified electrodes for the determination of trace amounts of Pb\u3csup\u3e2+\u3c/sup\u3e, Cd\u3csup\u3e2+\u3c/sup\u3e, and Zn\u3csup\u3e2+\u3c/sup\u3e via anodic stripping voltammetry

[Ru(NH3)6]3+/Nafion modified indium tin oxide (ITO) electrodes were fabricated via the drop coating technique and were used for the simultaneous determination of lead (Pb2+), cadmium (Cd2+), and zinc (Zn2+) in trace amounts using anodic stripping voltammetry (ASV). The amount of [Ru(NH3)6]3+ in the coating solution was varied at 5 mg, 10 mg, and 15 mg. The fabricated electrodes were used to detect varying concentrations of Pb, Cd and Zn. ASV results showed that as the amount of [Ru(NH3)6]3+ was increased, the reduction current of the heavy metals increased as well. The Pearson correlation values obtained for Pb and Cd were close to 1.0, indicating a strong positive linear relationship between the variables. The minimum heavy metal concentration that can be simultaneously detected by the fabricated electrodes is 0.5 ppm. © 2016 by De Gruyter