EQCM Study of the Redox Processes of Polyvinylferrocene Film in L-Glutamine Solution

Lei Yu, Meghana Sathe, Xiangqun Zeng
2005 Journal of the Electrochemical Society  
In this paper, we investigate the polyvinylferrocene ͑PVF͒ redox behavior in contact with a bathing solution containing L-glutamine ͑Gln͒ by electrochemical quartz crystal microbalance ͑EQCM͒. Our study shows that the interaction of PVF with Gln is dramatically different from PVF redox behavior in salt solutions, e.g., NaClO 4 . Rather than the doping of anion in anodic process and undoping of anion in cathodic process, Gln doping and undoping are observed in either anodic or cathodic process
more » ... cathodic process depending on the redox potential. This effect is rationalized by the strong preadsorption of Gln in the reduced PVF film and the local pH change that subsequently changes the Gln zwitterions charge states during the oxidation and reduction of PVF. OH − ions also act as counterions and play critical roles in the redox switching of PVF processes in Gln bathing solution. E357 Figure 4. The first three cycles of CV ͑a͒ and ⌬f vs E ͑b͒ curves in 0.05 M Blc-Gln, scan rate 5 mV/s. Scheme 2. Scheme 1.
doi:10.1149/1.2048230 fatcat:t44olmvcvbe4jhiz2q22becf44