Synthesis, characterization and electrochemical behavior of cationic iron porphyrin intercalated into layered niobate

Cationic iron porphyrin 5,10,15,20-tetrakis(N-methylpyridinium-4-yl) porphyrinato iron(III), FeTMPyP, has been intercalated into layered niobate (K4Nb6O17) through a guest-guest exchange method by using propylammonium niobate (PrNH3+-Nb6O17) as a precursor. The microstructure and morphology characterizations for the resulting material FeTMPyP-Nb6O17 have been investigated by means of XRD, FTIR and SEM. The UV-vis spectra results suggest that the incorporation of FeTMPyP in the bidimensional nanostructure produces a red-shift in the Soret absorption band of the cationic metalloporphyrin. By simple dropcoating method, FeTMPyP-Nb6O17 was used as a modifier on the glassy carbon electrode (GCE). The cyclic voltammetry (CV) curves exhibit nearly symmetric anodic and cathodic peaks, corresponding to the Fe(III)/Fe(II) couple. Furthermore, the anodic and cathodic peak currents are linearly dependent on the square root of scan rate, implying a fine diffusion-controlled electrode process. (C) 2011 Elsevier Inc. All rights reserved.