Spectral and electrochemical studies of methylene blue and thionine encapsulated in zeolite-Y

Abstract

Investigation on the spectral and electrochemical properties of methylene blue and thionine encapsulated in zeolite-Y is carried out. Both the dyes exist as monomer and H-aggregates in zeolites and the ratios for the aggregates of the dyes are different at the zeolite surface even though the dyes have similar basic structure. The electrochemical behaviour of thionine and methylene blue at zeolite modified electrode shows that both the dyes experience different environment at zeolite modified electrode and the presence of methyl groups in methylene blue plays a vital role in stabilizing the electroactive species at the electrode surface. The concentration of the supporting electrolyte is found to influence the nature of the redox process.