Bis-Tridentate Ir(III) Phosphors for High-Efficiency and Long-Lifetime Organic Light-Emitting Diodes

Organic light-emitting diode (OLED) is a lighting device in which the emissive layer is a film made of organic compound that emits light in response to the applied electric current. In recent days, this technology has been improved substantially such that both OLED display and lighting luminaries can have efficiency comparable or even better than the liquid crystal displays (LCD) and inorganic light emitting diodes (LED). Hence, relevant products have gained their importance in our daily life and acquired remarkable market value of several tens of billion dollars annually. This lighting industry consists of many distinctive innovation sectors such as material supplies, equipment, products design and manufacturing. At present, 90% of OLED related materials and end products sold in the global market were provided by companies located in the United States, Japan and Korea, despite that China has made a clear signal and wanted to become one major player in this arena within next few years. In order to overcome the technological blockade reinforced by these foreign companies, we must develop our own knowhow in materials, enabling local or domestic companies with fair access to the supplies and production technologies, and to bypass the current patent restriction on material designs and device fabrications.