High-temperature stable inverse opal photonic crystals via mullite-sol-gel infiltration of direct photonic crystals

Three-dimensionally ordered macroporous materials for photonic or refractory applications have been developed by an innovative approach based on mullite sol-gel infiltration of direct photonic crystals followed by burn-out and calcination. Direct photonic crystals were obtained using polystyrene spheres templates either by vertical convective self-assembly or by drop casting. The samples were then infiltrated by spin coating with mullite sol-gels prepared with two different compositions (74 wt.% Al 2 O 3 , 26 wt.% SiO 2 and 80 wt.% Al2O 3 , 20 wt.% SiO 2 ). The inverse opal photonic crystals prepared with both sol-gels presented a highly ordered porosity and the high-alumina composition showed stability up to 1500°C. After inversion of the structure (polymeric template burn-out), the high-alumina composition showed roundness of the PS templated pores closer to an ideal sphere (Ø = 0.967) when compared to the low-alumina composition (Ø = 0.954). Although the inverse opal photonic crystals did not present a photonic bandgap, they showed structural stability at high temperatures, which enable their application as refractory materials.

Subjects

high-temperature applications

infiltration, mullite sol-gel

photonic crystals

DDC Class

600: Technik

Funding(s)

SFB 986: Teilprojekt C5 - Oxidische Hochtemperatur-Schutzschichtsysteme mittels angepasster Porenstruktur

Lizenz

https://creativecommons.org/licenses/by-nc/4.0/

Name

Bueno_et_al-2018-Journal_of_the_American_Ceramic_Society.pdf

Size

1.88 MB

Format

Adobe PDF

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High-temperature stable inverse opal photonic crystals via mullite-sol-gel infiltration of direct photonic crystals