Titanium Oxide/Silicon Moth-Eye Structures with Antireflection, p-n Heterojunctions, and Superhydrophilicity

By employing KOH etching of silicon and hydrothermal growth of titanium oxide (TiO2), TiO2 nano rods assembled on the silicon micropyramids to form biomimetic composite coating, similar to moth-eye structures. The biomimetic composite coating possessed not only the micro-nano hierarchical structures but also the p-n heterojunctions, resulting in a decrease in the reflection of incident light and an increase in the separation efficiency of photogenerated carriers. Meanwhile, the structures showed excellent superhydrophilicity, making for the self-cleaning of the material surface. We further demonstrate that by exploiting the advantages of this method, the application of such structures in the photocatalysis field is thus straightforward.