Galvanic redox displacement

Dendrimer-templated synthesis of metal nanoparticles is a powerful technique and many metal DENs can be synthesized. However, the approach cannot be used to synthesize metal nanoparticles whose precursors (metal ions) have weak interactions with the dendrimers. For certain metal ions, such as Ag% another technique was developed based on galvanic redox displacement [68]. Using the galvanic redox displacement technique, Cu DENs were mixed with Ag. Since the standard reduction potential of Ag+ is more positive than Cu, Ag will be reduced to form Ag(0), and Cu(0) will be oxidized to Cu. Therefore, Cu DENs will be converted to Ag DENs using this technique. The conversion of Cu DENs to Au, Pt, or Pd DENs has also been demonstrated using the galvanic redox displacement technique [68]. 

Galvanic Cells. When you place a piece of zinc metal into a solution of CuSO, you expect a chemical reaction because the more active zinc displaces the less active copper from its compound. This is a redox reaction, involving transfer of electrons from zinc to copper. 

The electrochemical driving force for redox replacement reaction (galvanic displacement)... 

One approach to ALD of metals is a process known as surface-limited redox replacement or galvanic displacement. This method has been used to produce ultrathin layers of metals such as Pt, Pd, and Ag. - The ALD is brought about by the galvanic replacement of underpotentially deposited metal monolayers of less noble metals such as Pb or Cu. The surface-limited redox replacement occurs spontaneously, because the reduction potential of the less noble metal is more negative than that of the subsequent ALD layer. The two deposition steps in the surface-limited redox replacement of metals must be performed in separate solutions, so it is necessary to exchange reactants— much like the case of ALD by vapor deposition methods. 

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