Photo-physical studies of ruthenium(II) tris(1,10-phenanthroline) confined within a polyhedral zinc(II)-trimesic acid metal organic framework.

The development of new classes of photo-active porous materials is of specific interest in photocatalysis and light harvesting applications. Metal organic frameworks (MOFs) provide an excellent platform through which to develop photo-active materials as the large pores can serve as hosts for photo-active guests. Here the photophysical properties of [Ru(1,10-phenanthroline) 3 ] 2+ (RuPhen) encapsulated within a polyhedral Zn(II)-trimesic acid metal organic framework material, hereafter, USF2, are reported. Encapsulation alters the photophysical properties of the RuPhen exhibiting a biphasic decay of the triplet metal to ligand charge transfer state ( 3 MLCT) with lifetimes of 142 ns and 966 ns at 20 °C relative to 320 ns for RuPhen in deaerated ethanol solution. In addition, the encapsulated RuPhen displays a hypsochromic shift in the steady state emission relative to RuPhen in ethanol from 586 nm to 579 nm. These results are quite distinct from the corresponding RuBpy@USF2 and it is suggested that RuBpy and RuPhen encapsulate within different cavities of the USF2 framework. [ABSTRACT FROM AUTHOR]