Enhancement the catalytic activity of TiO₂ inverse opal nanostructures through binary and ternary heterojunction

Abstract

Efficient light harvesting through titania inverse opal nanostructures (TiO2 IOs) can be achieved by strategically engineering binary and ternary heterojunctions with various metal oxides. In this study, we developed two distinct binary heterojunctions involving titanium dioxide paired with tin oxide (TiO2–SnO2 IOs) and bismuth oxide (TiO2–Bi2O3 IOs), alongside a ternary heterojunction combining titanium dioxide, tin oxide, and bismuth oxide (TiO2–SnO2–Bi2O3 IOs). These IOs were synthesized using a soft template method. We employed transient absorption spectroscopy to assess the lifetime of photogenerated carriers in the IO systems, revealing a notably long lifetime exceeding 5 ns for all samples. Our investigation into photocatalytic activity demonstrated that both TiO2–Bi2O3 IOs and TiO2–SnO2 IOs binary heterojunctions exhibited enhanced performance, displaying 20 % and 5 % greater photocatalytic activity for acetylene degradation, respectively, compared to pure TiO2 IOs. Notably, the TiO2–SnO2–Bi2O3 IOs ternary heterojunction showcased a remarkable increase in photocatalytic activity, with a 53 % improvement over TiO2 IOs.