Electrochemiluminescence studies of the cyclometalated iridium(III) L2Ir(acetyl acetonate) complexes

Electrogenerated chemiluminescence (ECL) studies have been performed for the iridium(III) cyclometalated L2Ir(acac) complexes in 0.1 M (n-C4H9)4NPF6 acetonitrile–dioxane (1:1, v,v) solutions using a triple-potential-step technique. Electron transfer between electrochemically generated L2Ir(acac)+ cations and A− (radical anions of aromatic nitriles) leads to generation of the excited 3*L2Ir(acac) species. Extremely high ECL efficiencies (up to 0.55) close to the excited 3*L2Ir(acac) luminescence yields have been found.