High‐temperature stable inverse opal photonic crystals via mullite‐sol‐gel infiltration of direct photonic crystals. Issue 2 (17th September 2018)

• Record Type: Journal Article
• Authors: Bueno, Priscila; Pagnan Furlan, Kaline; Hotza, Dachamir; Janssen, Rolf
• Is Part Of: Journal of the American Ceramic Society. Volume 102:Issue 2(2019)
• Page Start: 686
• Page End: 694
• Publication Date: 2018-09-17
• Subjects: high‐temperature applications -- infiltration -- mullite sol‐gel -- photonic crystals; Ceramics -- Periodicals; 620.1405
• DOI: 10.1111/jace.16012
• Languages: English
• ISSNs: 0002-7820

Abstract

Abstract: 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.% Al2 O3, 26 wt.% SiO2 and 80 wt.% Al2 O3, 20 wt.% SiO2 ). 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.