Porphyrin-embedded organosilicas for detection and decontamination

Abstract

Porphyrin-embedded materials (PEMs) combine the tunable binding selectivity, high surface area, and low materials density of a highly ordered pore network with the unique properties of porphyrins. Porphyrins are a family of large, nearly planar molecules which strongly absorb visible light and fluoresce intensely. They are highly sensitively to alterations in their immediate environment making porphyrins valuable as indicators. They are well established electroand photocatalysts and have been used in this capacity in a wide range of applications. Surfactant-templated nanoporous organosilicas have great potential for the adsorption of small molecule contaminants. They can be synthesized with high surface areas, uniform pore dimensions, and ordered nanostructures while incorporating organic bridging groups in the pore walls that may be tuned for adsorption of a specific class of compounds. In the porphyrin-embedded materials, the organosilica scaffold stabilizes the porphyrin and facilitates optimal orientation of porphyrin and target. The materials can be stored under ambient conditions and offer exceptional shelf-life. The selectivity of the materials can be controlled both through incorporation of varying organic bridging groups in the organosilica structure and through selection of the porphyrin component.