| Near-infrared (NIR)-active materials are of technological interest for their potential applications in telecommunications, information storage, and biology sensors and for military purposes. This thesis consists of three parts with an overall objective of studying NIR-active ruthenium complexes and polymers, in particular the NIR electrochromism (chapter 2) and PL and EL properties (chapter 3) of the ruthenium complexes, and the photophysical properties of the ruthenium and other metal complex polymers (chapter 4).;First, to better understand the correlation between the structures and electrochemical and photophysical properties, four dinuclear ruthenium complexes with 1,2-dicarbonylhydrazido bridging ligand (DCH-Ru) with electron-withdrawing or electron-donating substituents are designed and synthesized. The resulting complexes show reversible redox properties and NIR electrochromism in the spectral region of 1150 to 1600 nm. The low oxidation potential and strong NIR absorption at 1150 nm are utilized to detect hydrogen peroxide in vitro at concentrations as low as 0.1 mM. Further utilization of energy transfer between a fluorescent dye and DCH-Ru complexes in different oxidation states, the electrochemically controlled photoluminescence is achieved.;Second, efforts have been made to extend ruthenium complex-based light emission beyond 1 mum by adjusting the LUMO level of the ligands and HOMO level of the metal center in complexes. Tunable photoluminescence and electroluminescence from 630 to 1040 nm have been achieved.;Third, a new series of polypyridyl-containing polymers and their metal complexes are obtained for studying their photophysical response to acid and some transition metal ions and NIR properties. Good selectivity and high sensitivity (e.g., 5 ppm level) for silver and palladium ions with these polypyridyl-containing polymers have been found. |
