Electrochemiluminescence from Organic Emitters

Abstract

Electrically induced light emission from conjugated organic molecules in a condensed phase has constituted one of the most investigated phenomena in the recent past for a variety of reasons. The considerable development achieved in this field has been mainly based on the search of new configurations for luminescent devices such as flexible large area light-emitting diodes, and in the synthesis of improved light-emitting organic materials. In the present review a particular aspect of electrically induced lightemission phenomena from organic materials is considered, namely, organic electrochemiluminescence, which is the phenomenon of light emission from excited organic molecules generated upon occurrence of electrochemically driven redox reactions. Such processes can produce luminescence in the visible range if the resulting oxidized/reduced forms of the conjugated organic molecules form excited species capable of emitting photons within the energy range 1.5-3.5 eV. Electrochemiluminescence from organic emitters in a condensed phase has led to the creation of devices such as light-emitting electrochemical cells, whose realization was decisive in the development of effective light-emitting devices. In the present review the description of the phenomena at the basis of organic electrochemiluminescence is given together with the description of materials and devices configurations for light-emitting electrochemical cells.

Synthesis and Electropolymerization of Hexadecyl Functionalized Bithiophene and Thieno[3,2-b]thiophene End-Capped with EDOT and EDTT Units

“…[2][3][4][5] They have proved useful in applications including sensors, [6][7][8][9] electrochromics, 10-13 organic light-emitting diodes, [14][15][16][17] photovoltaics [18][19][20][21] and field effect transistors. 3,4,22 These organic materials are attractive alternatives to their inorganic counterparts such as amorphous silicon due to cost-effective processability of the materials through solution deposition methods such as inkjet printing, spin coating and screen printing.…”

Doping front propagation in light-emitting electrochemical cells

“…[1][2][3][4][5][6][7] The drawbacks of LECs are that the turn-on time typically is slow and the operational lifetime is inadequate. In order to overcome these drawbacks it is fundamentally important to understand the physics behind their operation-a topic that has been intensely debated in the scientific literature, [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23] particularly regarding where the electric field in the device is largest and consequently most important.…”

Organic/Organic′ Heterojunctions: Organic Light Emitting Diodes and Organic Photovoltaic Devices

“…We also ignore the role of energy shifts which may occur at each of the contacting electrodes, which are important to both OLED and OPV device operation, and are summarized elsewhere. [46,[81][82][83][84][85][86][87][88][89][90][91][92] Charge , depending upon which has the smallest optical band gap): [97][98][99][100][101][102][103] heterojunctions, which appears to be important in controlling both OLED and OPV device efficiencies. [20,104,105] In the simplest description of this process, the excess free energy released in the charge recombination step (1) is controlled by differences in the frontier orbital energies for …”