F8BT

Classification

Polyfluorenes, Benzothiodiazoles, Organic semiconducting materials, Semiconducting polymers, OLED green emitter materials, OLED materials, Organic Photovoltaic materials, Polymer solar cells, OFET materials.

Applications

A widely used green emitting reference polymer for a variety of applications including as an emissive species in OLEDs, an approximately balanced p-type and n-type polymer for OFETs and light emitting transistors as well as being used a polymeric accepter for OPVs. The deep lying HOMO and LUMO levels (5.9 / 3.3 eV) make it air stable while the liquid-crystalline and beta phases make it widely used for basic research purposes.  

Usage Datasheet

For a high efficiency green OLED we recommend blending F8 with F8BT with the below specifications. This ink can then be applied either in air or in a glovebox with little difference in performance provided exposure time and light levels are minimised.
At typical concentrations of 10 mg/ml 100 mg of F8 (PFO) will make around 200 devices on Ossila's standard ITO substrates (20 x 15 mm) assuming 50% solution usage (50% loss in filtering and preparation).
OLED reference device:

• F8 with F8BT
• Blend ratio of 19:1 (F8:F8BT) in Toluene
• Total concentration of 10 mg/ml
• 0.45 μm PTFE filter
• Spun at 2000 rpm (approx. 70 nm thickness)

Pipetting 20 μl of the above solutions onto a substrate spinning at 2000 rpm should provide a good even coverage with approximately 70 nm thickness. The substrate needs to be spun until dry, which is typically only a few seconds — 15 seconds should be ample to achieve this. Thermal annealing should be undertaken at 80°C for 10 minutes prior to cathode deposition
A basic but efficient OLED can be made using PEDOT:PSS as a hole transport layer and Calcium/Aluminium as the electron contact. When used with the Ossila ITO substrates and shadow masks this produces an easy to fabricate yet efficient >100 cd/m2) device.

Uses

F8BT can be used with poly(9,9-di-n-octylfluorenyl-2,7-diyl) (PTO) to map the effect of noise sources on photoconducting charge transports by evaluating the conductivity and noise source density (N_t). It may also form a nanocomposite with single walled carbon nanotube (SWCNT) with excellent electric properties and high Seebeck coefficient, for potential application in the development of photovoltaic power and biomass energy. Organic light emitting diode (OLED) devices can be fabricated by depositing a blend of F8 and F8BT on PEDOT:PSS films.

General Description

F8BT is a fluorene copolymer that is used as a light-emitting polymer (LEP) with low energy of lowest unoccupied molecular orbital (LUMO), high electron mobility and luminance.