Light Emission from Nanocrystalline Si Inverse Opals and Controlled Passivation by Atomic Layer Deposited Al₂O₃

3D-nanostructured ensembles of silicon nanocrystals forming inverse opals, directly prepared by magnesioreduction, exhibited intense photoluminescence in a broadband range (visible and NIR). Light emission, which strongly diminished under photoexcitation, was preserved by engineering the nanocrystals interface with atomic layer deposition of alumina. The high accessibility of the nanocrystals throughout the self-supported structure was a key factor for efficient photoluminescence stabilization.