Immobilization of methylene blue on self- assembled iodine monolayers on gold

E. VELA, M; C. VERICAT,; DAZA MILLONE, A.; M. FONTICELLI,; G. BENITEZ,; R.C. SALVAREZZA; N TOGNALLI,; A FAINSTEIN,

Journal of Nanoscience and Nanotechnology

American Scientific Publishers

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 V3xV3 R30 deg 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 V3xV3 R30 deg  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 = 3-8) surface structures on Au(111).