Electrochemical and spectral properties of the composites of the alcian blue cationic phthalocyanine and silicododecamolybdate anions

Abstract

Polylayer composite of ultrathin silicododecamolybdate anionic layers and alcian-blue cationic layers (pyrydinium version), containing up to 10 bilayers, is assembled. The synthesis was performed by repeated dipping of glass plate, whose one side was precoated with indium-tin oxide (ITO), into aqueous solutions of the silicododecamolybdenum acid and alcian blue [the layer-by-layer (LbL-) deposition]). Optical absorption spectra showed that the composite LbL-film is a mixture of the associate and monomer forms of the alcian blue cation, which electrostatically interact with the silicododecamolybdenum acid anions [SiMo₁₂O₄₀]⁴⁻(SiMo). In a salt film, the silicododecamolybdenum-acid-to-alcian-blue interaction in the salt lattice promotes the deaggregation of the alcian blue molecules.