Characteristics and heterostructure of metal-doped TiO2/ZnO nanocatalysts

In this study, Ag or Al-doped TiO 2 /ZnO heterostructure nanocatalysts were prepared using a sol-gel method for photocatalysis to evaluate the degradability. The photocatalytic behavior was evaluated by the degradation of methylene blue (MB) under ultraviolet (UV) light irradiation. Photocatalytic studies suggested that 1 mol% Ag-doped TiO 2 /ZnO (TiO 2 /ZnO = 0.75/0.25) heterostructure nanocatalysts showed higher photocatalytic activity, and that the degradation efficiency can reach 83% in 4 h, 14% higher than that for pure TiO 2 . Finally, the photocatalysis mechanism for the Ag-doped TiO 2 /ZnO heterostructure nanocatalysts is discussed. • Ag or Al-doped TiO 2 /ZnO heterostructure nanoparticles were successfully prepared using the sol-gel method. • The best ratio of pure TiO 2 /ZnO is 0.75:0.25, and its photodegradation efficiency is 70% after UV irradiation for 4 h. • The best Ag or Al doped ratio is 1 mol%, and their photodegradation efficiency are 83.65% and 66.36%, respectively. • All the photocatalysts have better efficiency than pure TiO 2 , and the MB solution can be completely degraded after 24 h.