Vertical convective coassembly of refractory YSZ inverse opals from crystalline nanoparticles.

A facile deposition method of 3D photonic crystals made of yttrium-stabilized zirconia (YSZ) was developed. YSZ nanoparticles with primary particle size below 10 nm and cubic crystalline phase were synthesized by hydrothermal treatment of solutions of zirconyl nitrate, yttrium nitrate and acetylacetone. Before coassembly with polystyrene (PS) microspheres, a dispersant Dolapix CE64 was added to the dialyzed sol of YSZ nanoparticles to render their surface negatively charged.