Efficient Red Phosphorescent Electrogenerated Chemiluminescence Cell Based on a Combination of an Iridium Complex and a Carbazolyl Dicyanobenzene Derivative

Abstract

An efficient red phosphorescent electrogenerated chemiluminescence (ECL) cell was successfully designed by utilizing a cyclometalated iridium(III) complex and a carbazolyl dicyanobenzene derivative. The ECL solution, which contained bis(1-phenylisoquinoline)(acetylacetonate)iridium(III) (Ir(piq)₂(acac)) as a luminescent material and 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4CzIPN) as a redox mediator, was prepared and injected in a microfluidic ECL cell. The cell, which consisted of the 5-µm-thick microchannels sandwiched between transparent electrode pairs with the prepared solution, exhibited a saturated red emission with Commission Internationale de l'Éclairage (CIE) coordinates of (0.68, 0.31), a maximum luminance of 98.7 cd m⁻², and a maximum current efficiency of 1.63 cd A⁻¹. Photophysical and electrochemical studies were also carried out to support our experimental results.