CO chemisorption on platinum and palladium electrode studied by nuclear magnetic resonance

Nuclear magnetic resonance (NMR) is shown to provide insight on the electro nic properties of the chemisorption bond to-metallic electrodes of high spe cific surface area. The C-13-NMR of CO on Pt and Pd reveals the metallic ch aracter of the bond. The effect of varying the electrode potential on vario us NMR parameters has been studied in situ at-room :temperature. On platinu m, the change in the spectral line position with potential was about 50-70 ppm/volt. However, on palladium, no change in the spin-lattice relaxation t ime with the electrode potential could be detected so far, thus indicating a small change, if any, in the charge transfer between the CO and the surfa ce with the electrode potential. (C) 1998 Elsevier Science Ltd. All rights reserved.