Accession Number : ADA295505

Title :   Electroluminescent Diodes from a Single-Component Emitting Layer of Dendritic Macromolecules.

Descriptive Note : Technical rept. no. 1,

Corporate Author : ILLINOIS UNIV AT URBANA DEPT OF CHEMISTRY

Personal Author(s) : Wang, P. ; Liu, Y. ; Devadoss, C. ; Bharathi, P. ; Moore, J.

PDF Url : ADA295505

Report Date : 09 JUN 1995

Pagination or Media Count : 23

Abstract : Electroluminescent devices have been constructed using luminescent dendritic materials as the organic emitting layer. These dendritic macromolecules consisted of triphenylamines as the hole trapping groups, phenylacetylene segments for energy transfer, and 9,10-bis(phenylethynyl)-anthracene as the luminophor. These highly ordered, three-dimensional, covalent structures allow a modular approach to the design and construction of electroluminescent materials. X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) indicated that dendrimers of generation greater than 3 formed uniform, crack-free films of thickness 600-1200 A. Incorporation of triphenylamine units as hole trapping groups in dendrimer 2b increased the current density and lowered the turn on voltage as compared with its hydrocarbon analog 1c. Efficient energy transfer from phenylacetylene segments to the anthracene core is demonstrated by spectroscopic studies (absorption, emission, and excitation spectra). In the forward bias, these light emitting diodes (LEDs) radiate dim orange light. jg

Descriptors :   *DIODES, *ELECTROLUMINESCENCE, *MACROMOLECULES, *DENDRITIC STRUCTURE, *LIGHT EMITTING DIODES, EMISSION, FORWARD AREAS, SCANNING ELECTRON MICROSCOPES, CORES, SPECTROSCOPY, LAYERS, MATERIALS, COMPOSITE MATERIALS, EXCITATION, COVALENT BONDS, CRACKS, STRUCTURES, FILMS, CURRENT DENSITY, HOLES(ELECTRON DEFICIENCIES), ENERGY TRANSFER, TRAPPING(CHARGED PARTICLES), ELECTRON MICROSCOPY, AMINES, X RAY PHOTOELECTRON SPECTROSCOPY, HYDROCARBONS, ORGANIC MATERIALS, ABSORPTION, LUMINESCENCE, BIAS, PHENYL RADICALS, ORANGE(COLOR), ANALOG SYSTEMS, ANTHRACENES.

Subject Categories : Electrical and Electronic Equipment
      Organic Chemistry
      Physical Chemistry
      Polymer Chemistry
      Electricity and Magnetism
      Atomic and Molecular Physics and Spectroscopy
      Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE