Ching W. Tang
Wolf Prize Laureate in Chemistry 2011
Ching W. Tang
Affiliation at the time of the award:
University of Rochester, USA
“for exploring the nature of organic solids and their energy profiles, structure and dynamics and for creating new ways to make organic materials, ranging from polymers, to organic-based devices that capture energy from the sun, and light our way in the dark. The researchers have been responsible for groundbreaking conceptual and experimental advances that have helped to create the research field of organic materials”.
From wood to walrus tusks, and from amber to sugar, solid materials based on organic molecules are part of the natural world. The interest of the chemical community in such materials goes back to the days of the alchemists. However, the creation of new organic materials, the discovery of their properties, and then the development of new devices based on organic materials, has been one of the great chapters in the annals of chemistry over the past two centuries.
Professor Ching W. Tang (born 1947, Hong Kong) created two of the most active fields in organic materials, organic light emitting diodes (OLED) and organic photovoltaics (OPV). This spectacular work used some of the insights that Rice had characterized in organic crystals, to introduce a diode-type structure that in its subsequent development (by Tang and many others) has transformed the nature of optical displays. In 2011, OLEDs and OPVs span the range from fundamental scientific challenge to engineering improvement and industrial application. All this derives from Rice´s original insights and from Tang´s work in extending those concepts to deal with multi-component structures that can actually function as OPVs and OLEDs. The original paper by Tang (Applied Physics Letters, 1987), on organic electroluminescent diodes, is truly remarkable and constitutes testimony of the importance of Tang’s insights in combining the processes of photoexcitation and luminescence, charge separation and recombination, injection to and from electrodes, to produce these pioneering devices. Tang also pioneered the inverse process, in which photons incident on an organic crystal, generate electrons and holes that migrate to opposite electrodes, producing a current. This is the first workable example of a solar photovoltaic, based on organic materials.