Light-confining semiconductor nanoporous anodic alumina optical microcavities for photocatalysis

Abstract

An extensive study on the structural engineering of titanium dioxide-functionalized nanoporous anodic alumina optical microcavities (TiO2-NAA-μQVs) for photocatalysis enhanced by light confinement is presented.

Boosting visible light harvesting and charge separation in surface modified TiO2 photonic crystal catalysts with CoOx nanoclusters

“…5 Progress in the fabrication of metal oxide PCs based on bottom-up colloidal self-assembly techniques, 6 furnished fertile ground for the development of highly efficient UV and recently visible light activated (VLA) photonic catalysts. [7][8][9] These materials combine the unique potential for slow-photon-assisted light harvesting, mass transport and adsorption of macroporous periodic structures, such as inverse opals, 10 with compositional tuning of the catalysts' properties for enhanced charge separation and visible light activation. 7 The fundamental amplification mechanism is based on PBG engineering that enables spectral overlap of the slow-photon regime with the photocatalyst' electronic absorbance leading to the extension of the optical path length for incident photons within the periodic network, while evading Bragg reflection losses.…”

Realization of high-quality optical nanoporous gradient-index filters by optimal combination of anodization conditions

“…Recent efforts in pulse anodization have demonstrated the realization of NAA-PC structures such as multi-layered Fabry-Pérot interferometers (NAA-FPIs), distributed Bragg reflectors (NAA-DBRs), gradient-index filters (NAA-GIFs), bandpass filters (NAA-BPFs), optical microcavities (NAA-µCVs) and photonic tags. [27][28][29][30][31][32][33][34] NAA-PCs are composite photonic structures made up of air and alumina (aluminum oxide -Al 2 O 3 ). 26 The effective refractive index of NAA-PCs -average refractive index resulting from the relative fractions of NAA's individual components-can be engineered by a variety of pulse-like anodization strategies to generate specific structural arrangements for harnessing different forms of light-matter interactions (e.g.…”

Optical Platform to Analyze a Model Drug-Loading and Releasing Profile Based on Nanoporous Anodic Alumina Gradient Index Filters

“…Recent years have seen tremendous growth in the design and engineering of nanoporous structures based on modified anodization strategies. Therefore, it is possible now to control light-matter interaction and to fabricate advanced structures to be used in a broad range of applications in the field of biosensing [ 1 , 2 , 3 , 4 ], drug delivery [ 5 , 6 , 7 ], and photocatalysis [ 8 , 9 ]. Nanoporous anodic alumina photonic crystals (NAA-PCs) fall under the regime of optical materials having light modulation capabilities within the spectral regions (from Ultra-Violet to Infra-Red) allowing easy transport of molecules.…”