Researchers from South China University of Technology developed a new OLED structure that promises to enable low-cost efficient fluorescent OLED devices. The so-called pn-OLED structure is inspired by p-n junction theory and inorganic LED design. The pn-OLED uses a highly-efficient emission-layer-free OLED, in which the p-type and n-type organic semiconductors are sandwiched vertically between an ITO anode and a lithium fluoride/aluminum cathode. The luminescent center of the pn-OLED is located in the p–n junction region. The light-emission behavior of this device is a result of the synergetic energy release from both the p-type and n-type materials. This is in contrast to conventional OLEDs, where the light generation occurs from single-molecule emitters. Read more about pn-OLED structure may enable efficient and cost-effective fluorescent OLED devices

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pn-OLED structure may enable efficient and cost-effective fluorescent OLED devices