IMMOBILIZATION OF METHYLENE BLUE ON SELFASSEMBLED IODINE MONOLAYERS ON GOLD

MAR¨ªA E. VELA, C. VERICAT, A. DAZA MILLONE, M. FONTICELLI, G. BENITEZ, ROBERTO C. SALVAREZZA, NICOL¨¢S G. TOGNALLI, ALEJANDRO FAINSTEIN

Journal of Nanoscience and Nanotechnology

American Scientific Publishers

Lugar: Valencia, California; Año: 2006 vol. 6 p. 2362 - 2367

1533-4880

The immobilization of methylene blue (MB) on iodine-covered Au(111) is studied by electrochemical techniques, scanning tunneling microscopy (STM), Auger Electron Spectroscopy (AES), and Raman spectroscopy. Results show that MB species are efficiently adsorbed on the ¡Ì3¡Á¡Ì3 R30 I lattice on Au(111). The electrochemical behavior of the adsorbed MB molecules is reversible, indicating a relatively fast electron transfer from the Au(111) surface to the immobilized MB species through the iodine layer. STM images with molecular resolution are consistent with adsorption of MB dimers on a ¡Ì3¡Á¡Ì3 R30 I lattice placed atop of the Au(111) substrate. Results are compared to those obtained for MB immobilized on Au(111) covered by Sn (n = 3¨C8) surface structures.¡Ì3¡Á¡Ì3 R30 I lattice on Au(111). The electrochemical behavior of the adsorbed MB molecules is reversible, indicating a relatively fast electron transfer from the Au(111) surface to the immobilized MB species through the iodine layer. STM images with molecular resolution are consistent with adsorption of MB dimers on a ¡Ì3¡Á¡Ì3 R30 I lattice placed atop of the Au(111) substrate. Results are compared to those obtained for MB immobilized on Au(111) covered by Sn (n = 3¨C8) surface structures.