Layer-by-Layer Deposition of Pd on Pt(111) Electrode: an Electron Spectroscopy-Electrochemistry Study

作者：Hossain Mohammad A; Cummins Kyle D; Park Yeon Su; Soriaga Manuel P^*; Stickney John L

来源：Electrocatalysis, 2012, 3(3-4): 183-191.

DOI：10.1007/s12678-012-0102-5

• Surface-limited redox replacement reaction
• Galvanic-displacement electrodeposition
• Electrochemical atomic layer deposition
• Well-defined ultrathin Pd films
• Layer-by-layer electrodeposition of Pd on Pt(111)

Ultrathin palladium films, at coverages that ranged from one half to eight monolayers, were prepared, one layer at a time, on a well-defined Pt(111) single-crystal electrode surface by surface-limited redox replacement reaction (galvanic exchange) of Cu initially coated via underpotential deposition. Adlayers produced by the galvanic-exchange method were completely free of any residual Cu after the displacement-by-Pd step. Analysis of the current-potential profiles in the hydrogen-adsorption region indicated that at one monolayer coverage, the film was essentially pure terrace, devoid of steps, which did not exhibit hydrogen absorption. At higher coverages, a Stranski-Krastanov growth mode was manifested by the emergence of a voltammetric peak characteristic of hydrogen adsorption-desorption at step sites. Peaks diagnostic of hydrogen adsorption on both terrace and steps persisted even at a Pd-film thickness of eight monolayers; the intensities were considerably diminished, however, which indicated that hydrogen absorption into the now-bulk-like film had become dominant.

• 出版日期2012-12