Assembly and Optical Properties of Metal Complexes with Zirconium Phosphate
Photo antennas play an important role in the applications of solar energy. The efficient absorption and application of solar energy can be achieved through appropriate photo antenna systems. [Ru(bpy)32+] is a suitable chromophore for construction of artificial photo antennas, due to its unique properties. In this study, the inorganic lamellar materials were applied as the framework, and the luminescence properties of metal complex which can absorb visible light were improved through hybrid assemblies.
The modified zirconium phosphate containing hydrated α-ZrP and α-ZrP-BA, which have similar interlayer distance 10.4 A were prepared. The lamellar structure of materials can provide excellent opportunity for some chromophores to assemble.
The metal complex Ru(bpy)32+ Was incorporated within the layered materials, and their photophysical properties were studied to achieve excellent microenvironment for assembling of chromophores. The emission intensity and the excited, state lifetime of Ru(bpy)32+ evidently increased after the complex was bound to the hydrated α-ZrP framework. After the assembly suspension was deposited for a long time, the emission intensity of complex was hardly reduced. After complexes assembling with α-ZrP-BA, the luminescence intensity and the excited-state lifetime of the chromophore was also increased, but not strong as the former system. The luminescence decreased obviously, after depositing for some time. The different microenvironments result in different properties of luminescent complex. Therefore, the selection of appropriate layered material for the assembling of chromophore was of great importance.
The metal complex Ru(bpy)32+ has lively chemical activity at excited state, so the photoelectron transfer reaction can happen easily when the oxidant or reductant exists in the system. The luminescence of chromophore can be quenched in the reaction. The varieties of luminescence were studied in different systems (aqueous solutions, α-ZrP,hydrated α-ZrP and α-ZrP-BA) after the addition of oxidant or reductant. The interaction relationship of the chromophore with inorganic framework call be deduced from the phenomenon of the luminescence in different system. As a result, the excellent layered material can be chosen for assembling of the complex.
The novel zirconium phosphate material-hydrated α-ZrP has all inimitable superiority in improving the optical properties of Ru(bpy)32+, which is beneficial to achieve the application for construction of photo antennas.