Electrogenerated chemiluminescence of the platinum (II) octaethylporphyrin/tri-n-propylamine system

The electrogenerated chemiluminescence (ECL) of platinum (II) octaethyl-porphyrin (PtOEP) in acetonitrile:methylene chloride (CH₃CN:CH₂Cl₂, 50:50 v/v) and CH₂Cl₂ is reported. ECL was generated upon sweep to positive potentials using tri-n-propylamine (TPrA) as an oxidative-reductive coreactant. ECL efficiencies (?_ecl) of 0.18 in CH₃CN:CH₂Cl₂ (50:50 v/v) and 3.90 in methylene chloride were obtained using Ru(bpy)₃(PF₆)₂ (bpy = 2,2′-bipyridine) as a relative standard (?_ecl = 1). The ECL intensity peaks at a potential corresponding to oxidation of PtOEP and TPrA, and ECL emission spectra are nearly identical to photoluminescence emission spectra, indicating that emission is from the PtOEP triplet state.