The invention discloses a silver / 
titanium dioxide composite heterostructure. The silver / 
titanium dioxide composite heterostructure comprises a silver 
nanowire component and a 
titanium dioxide component, wherein a 
titanium dioxide shell covered with the silver 
nanowire can form a nuclear shell heterostructure, and a 
titanium dioxide ball is bunched on the silver 
nanowire so as to form a bradde chain heterostructure. The heterostructure provided by the invention has the good 
electricity-conduction and heat-conduction property of the silver, the heterostructure of a 
noble metal and a 
semiconductor photocatalyst is formed, the effective separation of electrons and holes is benefited, the 
photocatalytic degradation organic matter property is enhanced, the disadvantages that the 
chemical stability of the silver is poor, the surface of the silver is easy to oxidize, and the silver / 
titanium dioxide composite heterostructure has the wide application prospect on the 
photocatalysis and 
new energy field. The invention also discloses a preparation method, the operation of the method is simple, the 
controllability is strong, the 
repeatability is good, the heterostructures of different shapes are obtained through adjusting the 
collocation of a 
reagent, the size of the 
diameter of a TiO2 ball and the thickness of a titanium dioxide shell layer are adjusted by virtue of adjusting the quantity of a titanium source, and the preparation method has strong practicability.