Chemical Transformation from FePt to Fe_(1-x)PtM_x(M = Ru, Ni, Sn) Nanocrystals by a Cation Redox Reaction: X-ray Absorption Spectroscopic Studies

摘要

Recent, new synthetic approaches have been intensively explored to prepare new types of nanostructures using a chemical replacement reaction in a solution phase. The crystal compositions, structures, and shapes of starting nanocrystals might have been varied after they were chemically transformed into new types of nanostructures. For example, the studies on silver nanocrystals in the presence of gold ions have shown that the replacement reaction resulted in the product of gold nanocrystals with a significant shape transformation. The driving force of this specific reaction of the nanocrystals was attributed to the differences of the reduction potentials between silver and gold. Several other examples have also demonstrated that the new types of metal nanostructures, such as hollow, core/shell nanocrystals, or nanocrystal dimers, were formed under different reaction conditions.