Electrochemiluminescence of Copper(I) Bis(2,9-dimethyl-1,10-phenanthroline)
The electrochemical and electrochemiluminescence (ECL) properties of Cu[dmp]2+ (dmp = 2,9-dimethyl-1,10-phenanthroline) have been investigated. ECL has been observed for Cu(dmp)2+ in aqueous, nonaqueous, and mixed solvent solutions using tri-n-propylamine as an oxidative-reductive coreactant. The ECL intensity peaks at potential corresponding to oxidation of both the coreactant and Cu(dmp)2+. The peak potential corresponding to maximum ECL emission is ∼500 mV more anodic than corresponding oxidative peak potentials, indicating that the ECL emission may be due to the formation of either the *Cu(dmp)2+ metal-to-ligand charge-transfer excited state or an excited-state product of Cu(dmp)2+ oxidation. ECL efficiencies (φecl = photons generated per redox event) are solvent-dependent (φecl (CH3CN) > φecl (50:50 (v/v) CH3CN:H2O) > φecl (H2O)) and correspond fairly well with photoluminescence efficiencies. Increased ECL efficiencies (≥50-fold) are observed in the presence of the nonionic surfactant Triton X-100.
Chemistry and Biochemistry
metal to ligand charge transfer, solution chemistry, solvents, oxidation, excited states
McCall, Jeff, David Bruce, Scott Workman, Christopher Cole, and Mark M. Richter. "Electrochemiluminescence of copper (I) bis (2, 9-dimethyl-1, 10-phenanthroline)." Analytical chemistry 73, no. 19 (2001): 4617-4620.