Comparisons between Scanning Tunneling Microscopy and Outer-Sphere Electron-Transfer Rates at Pt(111) Surfaces Coated with Ordered Iodine Adlayers.

摘要

Rate parameters are reported for the electroreduction of eight CoIII(NH3)5X complexes at ordered Pt(111) surfaces coated with iodine adlayers whose structures are characterized by scanning tunneling microscopy (STM) in order to explore possible correlations between the outer-sphere electron-transfer kinetics and the spatially resolved adlattice properties as revealed by STM. The sixth ligands: acetates, and three cyclic organic carboxylates, were selected so to vary the reactant charge, and hence the magnitude of electrostatic double-layer effects, and to examine the effect of potential organic mediators. The ordered Pt(111) surfaces were prepared by flame annealing, followed by cooling in a stream of nitrogen over iodine crystals.