Synthesis and characterization of activated carbon–ethylenediamine-cobalt(II) tetracarboxyphthalocyanine conjugate for catalytic oxidation of ascorbic acid

Abstract

We report on the synthesis and characterization of activated carbon-ethylenediamine–cobalt(II) tetracarboxyphthalocyanine conjugate (AC–CONHCH2 CH2NH2–CoPc) and its electrocatalytic behavior for oxidation of ascorbic acid. Ultraviolet–visible (UV–Vis), Fourier-transform infrared (FTIR), and electrochemical impedance spectroscopies, and cyclic and square-wave voltammetry were used to characterize the electrode modifiers and modified glassy carbon electrode. The limit of detection was found to be 0.26 lm using 3d notation. The linear dynamic range was from 1.5 9 10-4 to 1 9 10-2 M with electrode sensitivity of 0.01 A mol-1 L cm-2. A Tafel slope of 200.8 mV decade-1 was found. The concentration of ascorbic acid in the tablet was 0.034 M. Oxalic acid showed no interference in ascorbic acid determination.