The Fabrication Of Cu₂S And Copper Group Nanocrystals

In recent years, inorganic nanocrystals with different size, morphology, and composition weresynthesized through the liquid-phase synthesis method. Owing their novel physical and chemical properties,they have the huge potential applications in the photoelectric device aspect. In a traditional method, thesynthesis and assembly of inorganic nanocryatals were mostly involved using organic ligands as surfacemodification agent. However, the insulating nature of such organic ligands typically results in very poorinterparticle coupling, which greatly hinder the photoelectric device in the application. It is found that metalchalcogenide complex as nanocrystal ligand enabled the facile fabrication of ordered superlattices withadvanced electronic and thermoelectric characteristics. Whereas the procedure for synthesizing orderedsuperlattices by inorganic ligands was as follows: first, Inorganic nanocrystal were synthesized; and then,inorganic ligands were introduced, which is not easy to realize.Therefore, designing a new surface ligand is necessary in the synthesis nanocrystals. This kindof ligand can not only adherence on the surface of nanocrystal, but also realize high charge transferefficiency. This new surface ligand can also effectively induce the self-assembly of individual nanocrystal.This paper focused on the synthesis of copper group nanocrystals in organic phase and the mainresults were as follows:（1） In chapter2, In chapter2, inorganic ligand Sn-X was used to replace traditional organicligand with long （short） hydrocarbon chains, Cu₂S nanocrystal modified with inorganic ligands was directlysynthetized through the introducing of inorganic ligands precursor in organic phase. InorganicSn-X-complex-induced self-assembled1D columnar,2D and3D stratiform anisotropic Cu₂S hexagonalnanoplates, which further induced the formation of the hexagonal lamellar structure. The factors （reactiontime, temperature, the concentration of Sn-X complex, and so on） that influence the size, phase,monodispersity, and self-assembly ability of the Cu₂S hexagonal nanoplates were studied in detail.（2） In chapter3, copper and silver nanocrystals modified with organic ligand oleylamine, whichwere synthetized by "one-pot" reation, have had high qulity and good monodispersity, and successfullyavoided some expensive raw materials. High quality metal nanocrystals have been got by changing the experimental conditions （temperature, surface active agents and different material concentrations）, whichestablished good foundation for copper group nanocrystals by inorganic ligands directly modified in thefurther step in organic synthesis.