Research On Synthesis And Growth Mechanism Of Metal Nanostructures With Various Shapes

Metal nanostructures,especially noble metal nanostructures,have attracted extensive attention due to their surface plasmon resonance(SPR)characteristics.The researches on the synthesis methods and growth mechanisms of metal nanostructures with different shapes will be helpful to promote the research progress of researchers in this field.The synthesis methods of metal nanostructures can be divided into top-down methods and bottom-up methods.In this research,several different synthesis methods and the surface plasmon resonance characteristics of noble metal nanostructures are briefly introduced,their application prospects in various fields are also prospected.In this research,gold nanorods(Au NRs)and gold nanocubes(Au NCs)were synthesized by a seed growth method.On the basis of these,Au-Ag core-shell nanorods(Au-Ag NRS)and Au-Ag core-shell nanocubes(Au-Ag NCs)were synthesized.Transmission electron microscopy(TEM)was used to study the growth mechanism of Au-Ag NRS and Au-Ag NCs.In the fourth part of this paper,we reported a synthesize of Au Cu alloy triangular nanostar(Au Cu TNSs)and Au Cu alloy pentagonal nanostar(Au Cu PNSs)in aqueous solution by a chemical reduction method.The morphology was observed by TEM and high resolution transmission electron microscope(HRTEM).It is the first time to suggest that the Au Cu triangular stars are grown from icosahedral seeds.Finally,we first report a successful synthesis of self-assembled Ag@Au Cu trimetal nanoplates in aqueous solution.The building blocks of multibranched Au Cu alloy nanocrystals were first synthesized by a chemical reduction method.The growth of Ag onto the Au Cu nanocrystals in the presence of hexadecyltrimethylammonium chloride(CTAC)induces a self-assembly process and formation of Ag@Au Cu trimetal nanoplates.These nanoplates with an average side length of over 2 ?m show a porous morphology and a very clear boundary with the branches of the as-prepared Au Cu alloy nanocrystals extending out.The shape and density of the Ag@Au Cu trimetal nanoplates can be controlled by changing the reaction time and the concentration of silver nitrate.The as-assembled Ag@Au Cu nanoplates are expected to have the potential for wide-ranging applications in surfaceenhanced Raman scattering(SERS)and catalysis owing to their unique structures.In each part,the application prospects of the synthesized metal nanostructures with different shapes are also prospected,which shows the broad application prospects of the metal nanostructures.