Size effect of Au nanoparticles in Au-TiO2-x photocatalyst

A model system of oxygen vacancy modified titanium dioxide (TiO 2-x ) nanobelts supported Au nanoparticles with different sizes is prepared for methylene blue photodegradation. The Au/TiO 2-x heterostructure with the smallest Au size exhibits the best performance than other samples. Based on detailed microstructural investigations, the effect of Au particle size on the photocatalytic performance is revealed in the view points of electron transfer mechanism and interface microstructure. It implicates that although the size effect determines the overall photoelectric properties of samples, it is the number and transport behavior of carriers at the interface that fundamentally affect the photocatalytic performance.