Preparation And Photocatalytic Degradation Performance Study Of The AuCu-p25-rGo Nanocomposite

In this thesis,we have successfully designed and prepared a new three-component bimetallic（AuCu alloy）nanocomposite AuCu-P25-rGO with rGO as the carrier and P25 TiO₂ as the active component,and been used as a high-performance photocatalyst.The morphology,chemical composition,physical structure and photoelectric property were confirmed by XRD,TEM,BET analysis,FT-IR,Raman,XPS,UV-vis DRS,Photoluminscence spectra and transient photocurrent responses techniques.The photocatalysts possessed higher catalytic activity than P25,P25-rGO,AuCu-P25,Cu-P25-rGO,Au-P25-rGO for photodegradation of organic pollutant（2-nitrophenol）under visible light.Importantly,the molar ratio of Au:Cu exhibited significant influence on the photocatalytic property,and AuCu-P25-rGO with Au:Cu molar ratio=1:1 showed better photodegradation performance than these with Au:Cu molar ratio=1:3 and 3:1.In addition,Au₁Cu₁-P25-rGO could excellently photodegradate organic dyes（Rhodamine B and methylene blue）.The enhanced photocatalytic performance of AuCu-P25-rGO composites can be attributed to four reasons as follows:（1）surface plasmon resonance（SPR）effect of AuCu bimetallic nanoparticles;（2）ultra-thin 2D nanostructure,outstanding conductivity and adsorptivity of rGO;（3）the polymorphs junction formed by mixture of anatase and rutile of P25;（4）the Ti-O-C chemical bond formed by the combination of rGO and P25 TiO₂ can effectively reduce the band gap of TiO₂.