Preparation And Characterization Of Gold-Cuprous Oxide Composited Interface Nanomaterials

Cu₂O was cheap and unique as a notable p-type semiconductor.It has been intensively studied for the applications in photocatalysis and photoelectric conversion,but it has the drawback of low charge-separation efficiency of photogenerated electron/hole paris which limits its development.In order to solve this problem,we have attempted to synthesis a series of the Au-Cu₂O samples with the low loading of Au in the galvanic replacement process which are different from the metal nanoparticles modified on the Cu₂O in the reported literature.Specifically speaking,we designed the Au-Cu₂O composite surface materials through embedding Au on the Cu₂O substrate surface.Then we put the Au-Cu₂O composites in the photo-degradation and photoelectric conversion properties.We analyzed the samples by regulating the synthesis methods,using the characterization methods and its performance test,then we knew the correlative rules of the samples about its synthesis,structure and performance.On the other hand,we have synthesized the new Au-Cu₂O composite interface materials successfully.It could provide a new sight on photocatalysis of the metal-Cu₂O composites as well as design more advanced Cu₂O-based photo-electric converting materials.Our representative research contents and results are as follows:?1?Controllable synthesis of samples is the basis of conducting the related research.In our woks,we synthesized a series of different morphologies of Cu₂O,and chose the nano cube Cu₂O as the substrate which could be synthesized in a large scale for the preparation of Au-Cu₂O composites.We also explored the experiment conditions in the process of synthesis which could have an influence on the samples about their morphologies,size and dispersion.At last,we selected the suitable preparation conditions to achieve the bulk of the samples preparation.?2?We found that the Au precursor in a low dosage range could have a significant impact on the surface structures of Au-Cu₂O samples and their performance.We characterized the samples through Raman,XRD,XPS,SEM and TEM.If we controlled the Au loading from 0.42 wt.%to 0.03 wt.%in the samples,we could find the state of Au which could be manipulated from Au?0?of the nanoparticles?ca.3.0 to 7.0 nm?to Au??+?.When we minimized the Au loading under the 0.06 wt.%level,the most of Au atoms could be highly dispersed and facilitate Au to exist as Au??+?species on Cu₂O surface.As a result,the photo-degradation activity and photoelectric conversion current density of the interface structure are doubled,it suggested that the Au-ionized Au-Cu₂O composite surface could be a more active catalytic structure to promote photocatalytic performance in comparation with Au nanoparticles attached Cu₂O surface.It may be a more efficient system or method to improve the charge-separation efficiency of photogenerated electron/hole pairs.This finding also predicted that it was worth further studying to have high photocatalytic performance with creating materials in which the metal cation completely and closely contacted on the surface of semiconductor.