ANYL 95 |
| The spectroscopy, electrochemistry, and electrogenerated chemiluminescence (ECL) of the organometallic complexes lithium tetra-(8-hydroxyquinolinato) boron (LiBHQ) and lithium tetra-(2-methyl-8-hydroxyquinolinato) boron (LiBMQ) is reported. These complexes are of interest for solid-state electroluminescent applications but their ECL has never been studied. ECL involves the generation of excited states at electrodes and is a powerful probe of energy and electron transfer events. LiBHQ and LiBMQ absorb light at approximately 300 nm and a produce an orange photoluminescence around 600 nm when in aqueous buffered solution (0.18 M potassium phosphate containing tri-n-propylamine (TPrA) as an oxidative-reductive ECL coreactant). In acetonitrile, LiBHQ absorbs at 319 nm and LiBMQ at 305 nm. Both emit light in a blue-green peak around 530 nm. The photoluminescence efficiencies are 0.0033 and 0.012 for LiBMQ and 0.0018 and 0.036 for LiBHQ in buffered solution and acetonitrile, respectively, when compared to a ruthenium 2,2'-bipyridine (Ru(bpy)32+) standard which has an efficiency of 0.05. Both complexes show quasi-reversible reductions at -0.93 V and irreversible oxidative waves. ECL efficiencies were 0.097 for LiBHQ and 0.080 for LiBMQ when compared to Ru(bpy))32+ which is assigned an ECL efficiency of 1. |
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General Papers
7:00 PM-9:00 PM, Sunday, 10 September 2006 Moscone Center -- Hall D, Poster
Division of Analytical Chemistry |