The effect of the pH value on microporous TiO2/ZnO heterostructure

Abstract

A novel microporous ZnO/TiO2 heterostructure, which consists of crystalline TiO2 decorated with amorphous ZnO, have been fabricated by a facile one-step synthetic methods. The results showed that the phase composition of the growing units and the intrinsic crystal structure are seriously controlled by the synthetic environment. Particularly, we have successfully captured the transformation process of the amorphous/crystalline heterostructure by adjusting the pH value. A microporous TiO2/ZnO composite photocatalyst consisting of crystalline TiO2 nanoparticles decorated with amorphous ZnO is fabricated by low-temperature hydrothermal treatment. And the pH value during the preparation of the new configuration photocatalyst affects the crystalline structure and BET surface area. The sample with high pH value (8~12) is favorable to the formation of an amorphous/crystalline composite structure with large micropore area and BET surface area. When the pH value is 12, the novel photocatalyst not only exhibits the excellent photocatalytic activity of hydrogen evolution from water splitting, but also has a large micropore area.