Near-quantitative internal quantum efficiency in a light-emitting electrochemical cell.
A green-light-emitting iridium(III) complex was prepared that has a photoluminescence quantum yield in a thin-film configuration of almost unity. When used in a simple solid-state single-layer light-emitting electrochemical cell, it yielded an external quantum efficiency of nearly 15% and a power efficiency of 38 Lm/W. We argue that these high external efficiencies are only possible if near-quantitative internal electron-to-photon conversion occurs. This shows that the limiting factor for the efficiency of these devices is the photoluminescence quantum yield in a solid film configuration. The observed efficiencies show the prospect of these simple electroluminescent devices for lighting and signage applications.
Bolink
Henk J
HJ
Instituto de Ciencia Molecular, Universidad de Valencia, P.O. Box 22085, ES-46071 Valencia, Spain. henk.bolink@uv.es
Coronado
Eugenio
E
Costa
Rubén D
RD
Lardiés
Nora
N
Ortí
Enrique
E