title: Electrochemically deposited organic luminescent films: the effects of deposition parameters on morphologies and luminescent efficiency of films.
abstract: The electropolymerization behaviors of an electroactive and luminescent compound TCPC as precursor are studied. The resultant electrochemical deposition (ED) films are characterized by cyclic voltammetry (CV), UV-vis, fluorescence spectra, scanning electron microscopy (SEM), and atomic force microscopy (AFM). Under the CV mode with potential range of -0.5 to 0.85 V vs Ag/Ag(+), the coupling reactions between the carbazole units of TCPC are very efficient, while the fluorescent trifluorene segment in TCPC is chemically inert in this potential range, which results in a highly fluorescent film formation on indium tin oxide (ITO) electrode. The deposition parameters for preparing the TCPC-based ED films are optimized, and the best ED film gives the fluorescence efficiency of 45.5% with surface roughness of 2.8 nm and morphologic stability as heating to 180 degrees C. The light-emitting devices (LEDs) using this ED film as light emitting layer with structure ITO/ED film (approximately 100 nm)/Ba/Al achieve maximum luminescence and external quantum efficiency of 4224 cd/m(2) at 17 V and 0.72% at 11.5 V, respectively, which are better than the device using TCPC spin-coating films as emitting layer. The technique provides a facile route toward a patternable luminescent film and device because such luminescent ED films can be manipulatively deposited on the electrified electrode.
authors.affiliation: Key Laboratory for Supramolecular Structure and Materials of Ministry of Education, Jilin University, Changchun 130012, China.
authors.forename: Mao
authors.initials: M
authors.lastname: Li
authors.forename: Shi
authors.initials: S
authors.lastname: Tang
authors.forename: Fangzhong
authors.initials: F
authors.lastname: Shen
authors.forename: Meirong
authors.initials: M
authors.lastname: Liu
authors.forename: Weijie
authors.initials: W
authors.lastname: Xie
authors.forename: Hong
authors.initials: H
authors.lastname: Xia
authors.forename: Linlin
authors.initials: L
authors.lastname: Liu
authors.forename: Leilei
authors.initials: L
authors.lastname: Tian
authors.forename: Zengqi
authors.initials: Z
authors.lastname: Xie
authors.forename: Ping
authors.initials: P
authors.lastname: Lu
authors.forename: Muddasir
authors.initials: M
authors.lastname: Hanif
authors.forename: Dan
authors.initials: D
authors.lastname: Lu
authors.forename: Gang
authors.initials: G
authors.lastname: Cheng
authors.forename: Yuguang
authors.initials: Y
authors.lastname: Ma