Effect of Organic Additives on Underpotential Deposition

The effect of acetate, citrate, and thiourea on Pb underpotential deposition on Ag(lll) has been studied. The effects of the anionic character of the additives were discussed in relation to changes in voltammograms. The two-dimensional phase transformation was also discussed. The influence of various additives such as dimethylfluoride (DMF) and pyridine on cyclic voltammograms of Cu underpotential deposition on Pt(lll) was observed. Cu underpotential deposition on Pt(lll) was studied in the presence of crystal violet, coumarin, and hydroquinone.  

The addition of crystal violet to a Cu underpotential deposition systen on Au(l 11) gave two different STM images at potentials different from the images seen in its absence. One of these was due to the presence of Cr as a counteranion in the crystal violet molecule. Thiourea was added to Cu underpotential deposition on Au(lll) to investigate the 

---