Chlorine increases OLED efficiency while reducing costs

Chlorine has many uses in society, be it sanitising your local pool from grubby individuals or providing freshly bleached jeans for marauding groups of English skinheads.

But now boffins at University of Toronto have found that chlorine can help create ultra efficient OLED flat panel displays and lighting for a variety of appliances with just a one atom-thick layer of the chemical.

The scientists devised a method of creating the organic light-emitting diode (OLED) devices that significantly reduces the complexity of the technology and improving its efficiency by engineering a thin sheet of cholrine onto the industry standard indium tin oxide electrode material that is currently found in flat panels.

Essentially the scientists were able to create a more efficient medium for electrical transfer rather than the usual “several costly layers” that are traditionally used.

The researchers were able to do this by developing a UV light assisted process to achieve chlorination rather than less reliable and more hazardous chlorine gas.

“It turns out that it’s remarkably easy to engineer this one-atom thick layer of chlorine onto the surface of ITO,” says researcher Michael Helander.

When tested, the scientists found that the new Cl-OLED performed markedly better at very high brightness in comparison to standard OLEDs, which are themselves regarded as highly efficient as a display.

According to Helander “the challenge in conventional OLEDs is that as you increase the brightness, the efficiency drops off rapidly,” but by chlorinating the ITO they were able to double the efficiency of OLEDs.

The scientists claim that their method can also reduce costs by simplifying the manufacturing process, “reducing the number of manufacturing steps and equipment,” and will help enable mass production of OLED devices into the mainstream for display panels in the future, with larger products currently on the market often seen at the higher end of the price spectrum.