Optical Performance Study of Gyroid-Structured TiO2 Photonic Crystals Replicated from Natural Templates Using a Sol-Gel Method

Photonic crystals with novel nanostructures have attracted huge attention due to their potential applications in manipulation of light propagation and next-generation energy and information technologies. In this work, TiO2 photonic crystals with 3D bicontinuous gyroid structure in visible light wavelength range are successfully fabricated by templating from natural templates using a sol-gel method. This is the first time to report controlling the volume fraction (VF) through regulating the rinsing time of templates in the sol-gel precursor. Gyroid-structured TiO2 photonic crystals (GTPCs) with different VFs, 3.2, 8.0, and 13.5% are obtained. Combined with finite-difference time-domain simulations, the photonic bandgap properties of the GTPCs are systematically studied. Based on this work, one step is moved further toward the exploitation of the optical performance of the GTPCs in visible light wavelength range beyond the previous simulation works.