Beneficial Effects of Cetyltrimethylammonium Bromide in the Modification of Electrodes with Cobalt Hexacyanoferrate Surface Films

A new strategy involving the introduction of a cationic surfactant, cetyltrimethylammonium bromide (CTAB), for the modification of electrodes with cobalt hexacyanoferrate (CoHCF) film has been found to be beneficial. The surfactant has been found to influence the electrochemical properties of the CoHCF-modified electrode by way of enhancement of voltammetric currents and reversibility of redox reactions. CoHCF surface films deposited by a potential cycling procedure in the presence and absence of CTAB are compared for K+ transport characteristics, using cyclic voltammetry (CV). CV parameters in 0.1 M KCl + 0.1 M HCl for electrodes modified both in the presence and in the absence of CTAB and diffusion coefficient values obtained from double potential step chronocoulometry at different pulse widths are presented and discussed. A comparative study is made for the transport behavior of K+, Na+, Li+, and NH4 + ions through CoHCF films, prepared both in the presence and in the absence of CTAB.