Large-area, crack-free polysilazane-based photonic crystals

Large-area, crack-free inverse opal photonic crystals were successfully fabricated by conventional colloidal self-assembly method with poly(St-MMA-AA) as the opal template and a thermosetting polysilazane as the infiltrating polymer. The phenomenon of self-healing of cracks in the opal template was observed and attributed to the unique rheology property of the used polysilazane. Under an optimized pyrolysis condition, a hybrid inverse opal photonic crystal with its refractive index at 2.21, filling fraction of the solid material at 0.66, and area around 8 mm × 10 mm was prepared.