Walter Weare, a professor in inorganic chemistry at North Carolina State University has discovered a new simple method for producing OLEDs without toxic by-products. The technique has already been used to produce an OLED which gives a bright orange light and Weare's team is now pursuing additional funding to develop the process.
The main breakthrough in Weare's approach has been to find a way to forge carbon to carbon bonds by introducing a metal element, like chromium, to an existing compound with molecules formed of a carbon oxygen double bond - called a ketone or alkanone. A carbon-carbon bond is then formed with the only chemical released being oxygen. Existing OLED material fabrication techniques employ petrochemicals and iridium and release potentially harmful substances like tin, bromine or chlorine.
The ketone reaction is carried out in an environment at around 150°C, produced using microwave heating. Extra funding has now been secured to extend the research project into the second half of 2014, so as to further refine the new method.
A simpler chemical process would reduce the overall costs of OLED materials in all applications and the development of an orange OLED hints at other interesting possibilities for lighting and consumer devices.
Weare says: 'The current ways that other people make the same types of compounds are multiple steps, where you get groups that you have to throw away at the end. Ours is both technically simpler and creates less polluting by-products. It is all only carbon and oxygen, so you are not throwing away heavy metals; you are just making tar. The only waste is really if our reaction does not work.'
By John Nelson, follow John on Google+
No comments:
Post a Comment