Mesoporous bragg stack color tunable sensors.

Sung Yeun Choi; Marc Mamak; Georg von Freymann; Naveen Chopra; Geoffrey A Ozin

doi:10.1021/nl061580m

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PubMed · 17090073

Mesoporous bragg stack color tunable sensors.

Sung Yeun Choi·Marc Mamak·Georg von Freymann·Naveen Chopra·Geoffrey A Ozin

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Abstract

Herein we report a novel self-assembly synthesis, structural and optical characterization of mesoporous Bragg stacks (MBS) composed of spin-coated multilayer stacks of mesoporous TiO(2) and mesoporous SiO(2). Investigation of the optical response of MBS to the infiltration of alcohols and alkanes into its pores reveals better sensitivity and selectivity than conventional Bragg reflectors. Furthermore, we demonstrate that the chemical sensing ability can be tuned via layer thickness, composition and surface properties.

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Adsorption Alcohols Alkanes Materials Testing Membranes, Artificial Microscopy, Electron, Scanning Optics and Photonics Particle Size Porosity Sensitivity and Specificity Silicon Dioxide Surface Properties Titanium Journal Article Research Support, Non-U.S. Gov't

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Sung Yeun Choi, Marc Mamak, Georg von Freymann, Naveen Chopra, Geoffrey A Ozin. 2006. Mesoporous bragg stack color tunable sensors.. https://doi.org/10.1021/nl061580m

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