A Poly-p-nitrostyrene on Platinum Electrode. Polymer Charging Kinetics and Electrocatalysis of Organic Dihalide Reductions

Article abstract of DOI:10.1021/ja00530a014

Platinum electrodes were modified by dip coating them with poly-p-nitrostyrene from a N,N-dimethylformamide solution.The coated electrodes were dried and then used for electrochemical studies in dry acetonitirile containing tetraalkylammonium fluoroborate electrolytes.Cyclic voltammetry showed that cycling the potential of these electrides from -1.0 to -1.8 V vs. a Ag/AgNO3 reference produced some initial desorption and formation of a stable polymer layer which was charged and discharged with peak potentials of -1.6 V.The peak shapes and the dependence of the voltammograms on the sweep rate, electrolyte cation, and amount of adsorbed polymer provided evidence about the structure and about the kinetics and thermodynamics of charging.The catalyzed reduction of 1,2-dibromo-1,2-diphenylethane to stilbene was investigated using cyclic voltammetry and preparative electrolysis.It was shown that the efficiency of catalysis increased to a limiting value as the amount of chargeable polymer increased.High efficiencies for reduction of this dihalide (3 mm) in acetonitrile could be obtained with layers corresponding to a surface charged of 4 nM cm^-2.The turnover number for catalyst sites was estimated to be 10⁴.