Effect of copper ions on the formation of hydrogen peroxide from photocatalytic titanium dioxide particles

摘要

Reactive radicals such as hydroxyl radical (OH) hydrogen peroxide (H_2O_2) and superoxide anion (O_2~-) are the main power driving titanium dioxide (TiO_2) photocatalytic reactions for example photokilling of biological cells Here the effect of copper ions on the formation of H_2O_2 over photocatalytic TiO_2 was investigated Under an oxygen-purged solution formation of H_2O_2 formed can be converted into OH a highly reactive radical In contrast under nitrogen-purged solution no H_2O_2 was formed even in the presence of an electron acceptor silver ion(Ag~+) These result clearly show that H_2O_2 was generated from the reduction site of the photoexcited TiO_2 and indicate and effective way to increase the photocatalytic efficiency.