|
Photonic bandgap (PBG) crystals, which are the artificial multi-dimensional periodic structures, are attractive for novel optoelectronic devices. Inverse opal structures are formed when polymer spheres are surrounded by skeletal dielectric materials. The important issue for the fabrication of inverse opal structures is the filling functional materials with fewer defects and larger filling ratio. Gold nanoparticles (AuNP) have received much attention as biosensor and optoelectronic devices for their novel electronic, optical, and surface properties. In this paper, we fabricated gold-nanoparticle-infiltrated inverse opal structures, which have both photonic bandgap and surface plasma characteristics.
We demonstrate a simple method to fabricate inverse-opal structures with tunable photonic band-gaps. Firstly, we can control the bandgap position by utilizing hybrid polystyrene (PS, 300 nm) and silica beads (12 nm) with different concentration-ratio. We can fabricate the inverse opal structure by annealing and sintering the sample. After annealing, the PS spheres are vaporized and silica spheres remained. The silica spheres are formed a hollow silicate shell after the sintering process. The inverse opal structure that surface functionalized with (3-aminopropyl)trimethoxysilane) APTMS is immersed into solution with gold nanoparticles, then gold nanoparticles can infiltrate in inverse opal structures. Gold nanoparticles are found not only on the surface but also in the bottom of inverse opal structure. We measure transmission spectra of the inverse opal structure with different incident angle. At normal incidence, the transmission dips of 520 nm and 620 nm are found and due to the localized surface plasmon resonance absorption of gold nanoparticles and the photonic bandgap of inverse structure, respectively. As increasing the incident angle, the photonic bandgap position is blue shift, and the surface plasmon resonance absorption dip is remained at 520 nm. The result indicates the gold-nanoparticle-infiltrated inverse opal structure with both photonic bandgap and surface plasmon resonance characteristics. Detailed analysis and results will be reported in the conference.
|