Optical Properties of Porphyrin Chromophores Assembled in Nano-Lamellar Zirconium Phosphate
Abstract:The supra-molecular assemblies and optical properties of the symmetrical neutral porphyrin chromophore, meso-tetra(4-pyridyl)porphine, bound to a modified α-zirconium phosphate framework have been studied. The interlayer distance of the cetyltrimethylammonium zirconium phosphate framework is 39.6 Å. After the addition of meso-tetra(4-pyridyl)porphine to the framework, the X-ray powder diffraction (XRPD) patterns show that the interlayer distance of the framework is 30.3 Å, demonstrating the formation of novel assemblies. In the framework, organic chromophores are assumed to align in a canted monolayer. The interaction of organic chromophores with the frame-work causes noticeable red shifts of the Soret absorption band from 416 to 427 nm. In contrast, the luminescence peak is blue shifted from 660 nm in aqueous media to 648 nm when mesotetra(4-pyridyl)porphine is bound to the framework. Furthermore, the emission yield of the organic chromophore in the framework is dramatically enhanced compared to that of organic aqueous solutions. The spectroscopic change of meso-tetra(4-pyridyl)porphine is ascribed to the unique microenvironments of the nano-lamellar framework. The juxtaposition of the porphyrin chromophores in the framework tunes their electronic interactions. In comparison, the organic chromophores also attempted to bind with another modified α-zirconium phosphate, n-butylammonium zirconium phosphate. However, the chromophores could not enter into n-butylammonium zirconium phosphate due to its smaller interlayer distance (18.8 Å).
Document Type: Research Article
Publication date: March 1, 2008
More about this publication?
- Journal for Nanoscience and Nanotechnology (JNN) is an international and multidisciplinary peer-reviewed journal with a wide-ranging coverage, consolidating research activities in all areas of nanoscience and nanotechnology into a single and unique reference source. JNN is the first cross-disciplinary journal to publish original full research articles, rapid communications of important new scientific and technological findings, timely state-of-the-art reviews with author's photo and short biography, and current research news encompassing the fundamental and applied research in all disciplines of science, engineering and medicine.
- Editorial Board
- Information for Authors
- Subscribe to this Title
- Terms & Conditions
- Ingenta Connect is not responsible for the content or availability of external websites