Hyelim Kang, Joon-Seok Lee, Won Seok Chang, and Shin-Hyun Kim, "Liquid-Impermeable Inverse Opals with Invariant Photonic Bandgap," Advanced Materials, accepted for publication (2014).
Omniphobic inverse opals are created by structurally and chemically modifying surface of inverse opals through reactive ion etching. During the etching, void array of inverse opal surface evolves to triangular post array with re-entrant geometry. The elaborate structure can efficiently pin air-liquid interface and retain air cavities against water and oil, thereby providing liquid-impermeable inverse opals with invariant photonic bandgap.