Palladium and Platinum Deposition onto 4-Mercaptopyridine SAMs
A novel technique has recently been presented for depositing metal layers onto a SAM. This is demonstrated here for Pd and Pt deposits on a mercaptopyridine (4-PyS) SAM. The SAMcovered Au(111) electrode is immersed into the metal-ion-containing solution without potential control. As a result, metal ions, e.g., Pd(II) (respectively Pt(II)) adsorb on the surface by forming a complex with the pyridine species. Subsequently, the electrode is transferred to a metal-ion-free solution, where the adsorbed metal ions are reduced electrochemically to its zero-valent state. Upon reduction, monoatomic high metal islands were observed in STM. Angle resolved XPS measurements show unequivocally that the reduced metal resides on top of the SAM.
Chunli BAI, Sishen XIE, Xing ZHU
V. Ivanova et al., "Palladium and Platinum Deposition onto 4-Mercaptopyridine SAMs", Solid State Phenomena, Vols. 121-123, pp. 363-368, 2007