Effects of Cesium Carbonate Doping on Blue Organic Light-Emitting Diodes (OLEDs)
Abstract
Low-work function metals, such as Lithium, Sodium, Potassium and Cesium, doped with suitable organic host materials as an electron injection and electron transport layer have been used in Organic Light-Emitting Diode (OLED) devices to lower device driving voltage. However, the practical process was greatly limited by lack of suitable organic host materials and difficult for using these active metals during device fabrication processes due to their extreme reactivity. In our designed OLED devices, we used alkaloid salt, cesium carbonate (Cs2CO3) which is very stable under environmental atmosphere, instead of extremely active low-work function metal, doped with widely used electron transport material 1, 3, 5-Tri(1-phenyl-1H-benzo[d]imidazol-2-yl)phenyl (TPBI) as an electron injection and transport layer. Our results demonstrated that OLED devices produce significant low voltage, and deep blue emission by using Cs2CO3 doped TPBI as an electron injection and transport layer; Alkaloid salt Cesium Carbonate can be used as an alternative for low-work function metal guest material in OLED devices to achieve low voltage, efficient electroluminescent (EL) devices instead of using hazard, highly reactive metals; Alkaloid salt Cesium Carbonate can be used in wide concentration range without significant affect driving voltage and EL efficiency of doped EL devices, which will gain significant yield for the OLED fabrication process.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 2014
- Accession Number
- AD1116873
Entities
People
- David Morton
- Eric Forsythe
- Jianmin Shi
- Merric Srour
- Richard Fu
- Steven Blomquist
Organizations
- United States Army Research Laboratory