A team of researchers from Pohang University of Science and Technology (POSTECH), UNIST, and Hanyang University in Korea have developed a photomultiplication-type organic photodiode (PM-OPD) that does not require an electron receptor. The PM-OPD is an optical device that efficiently amplifies visible light into electrical signals, excelling in low-light conditions. The researchers employed a perfluoroarene-based photo-crosslinker to enhance the electrochemical stability of the device, replacing the electron acceptor. By disassembling the exciton into discrete electrons and holes, the PM-OPD achieved optical amplification without the need for the electron acceptor, a crucial component in conventional designs. The team also successfully fabricated an organic image sensor with exceptional sensitivity, stability, and full-color capability, paving the way for the future commercialization of organic image sensors.
The researchers’ breakthrough could have significant implications for various applications such as biometric recognition technology, cameras, and optical communications. Organic photodiodes are capable of recognizing various colors without the need for color filters, making them valuable in a wide range of industries. The use of the perfluoroarene-based photo-crosslinker enhanced the electrochemical stability of the PM-OPD, allowing it to efficiently convert light into electrical signals even in low-light conditions. This is achieved through the absorption of photons, resulting in the creation of electrons and holes at the interface between the electron donor and the perfluoroarene. The PM-OPD disassembles the exciton into discrete electrons and holes, catalyzing the generation of additional holes and ultimately enhancing the flow of current.
The researchers also achieved a major milestone by developing an organic image sensor with exceptional sensitivity, stability, and full-color capability. They patterned the PM-OPD according to the three primary colors of light (red, green, and blue) on the sensor’s surface, allowing it to accurately capture and process full-color images. The team believes that their research breakthrough will greatly contribute to the future commercialization of organic image sensors. The study was sponsored by Samsung Future Technology Incubation Program.