Hydrohalic-acid anion interaction with gold surfaces: Au(100) – bromide
In this chapter the experimental results on adsorption of bromide ion on Au(100) surface is described.
In 0.1 M H2SO4 + 1 mMKBr solution, bromide adsorption begins at −0.12 V (SCE) and results in the formation of a disordered Brad layer which lifts the Au(100) reconstruction accompanied by island formation. At +0.1 V (SCE), a phase transition and the formation of a c(√2 × 2√2)R45° structure are observed, and starting at 0.48 V (SCE), i.e., with increasing coverage, a further commensurate-incommensurate transition into a c(√2×p)R45° phase (with p ≤ 2√2), i.e., a uniaxial, continuous compression phase, occurs whose coverage increases from 0.5 to 0.65 ML with increasing potential.
While bromide resides in the hollow sites on Ag(100), it prefers the twofold bridge sites on Au(100) as concluded from DFT calculations.
density functional theory
saturated calomel electrode
- 5.Lucas, C.A., Markovic, N.M.: In-situ X-ray diffraction studies of the electrode/solution interface. In: Alkire, R.C., Kolb, D.M., Lipkowski, J., Ross, P.N. (eds.) Advances in Electrochemical Science and Engineering, vol. 9. Wiley-VCH, Weinheim (2006). ISBN:3-527-31317-6Google Scholar