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.

Report Date:

1995-06-09

Pagination or Media Count:

23.0

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-bisphenylethynyl-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