Abstract
Two-dimensional (2D) inverse opal ZnO nanorod networks exhibiting a photonic crystal band gap have been grown by an aqueous chemical method with nanosphere lithography at low temperatures. The 2D ZnO photonic crystals with band gap at the green light emission region have been successfully fabricated for the first time. The presence of the photonic band gap was inferred from the reflection spectra and confirmed by the photonic band calculation. The ZnO nanorod networks exhibit prominent blue shift at UV emission and almost no green emission attributed to singly ionized oxygen vacancies. The combination of aqueous chemical growth and nanosphere lithography provides a large-scale, facile, and low-cost fabrication method at low temperatures, which shall be of significant value for practical applications of the grown photonic crystals. c 2009 American Chemical Society.