Etude du transport local de charges dans les couches semi-conductrices désordonnées par spectroscopie à une molécule

BORDEAUX1-BU Sciences-Talence (335222101) / SudocSudocFranceF

Ultra-Bright, Highly Efficient, Low Roll-Off Inverted Quantum-Dot Light Emitting Devices (Qleds)

We report an ultra-bright, highly efficient, low roll-off, inverted quantum dot-based red light emitting device (QLED) using solution-processed zinc oxide nanoparticles and cesium carbonate films as the electron injection and hole blocking layers, respectively. Record luminance of 165, 000 Cd/m2 has been obtained at a current density of 1000 mA/cm2 with a low driving voltage of 5.8 V for deep red device with C1E coordinates of (0.69, 0.31)

QLEDs for displays and solid-state lighting

The mainstream commercialization of colloidal quantum dots (QDs) for light-emitting applications has begun: Sony televisions emitting QD-enhanced colors are now on sale. The bright and uniquely size-tunable colors of solution-processable semiconducting QDs highlight the potential of electroluminescent QD light-emitting devices (QLEDs) for use in energy-efficient, high-color-quality thin-film display and solid-state lighting applications. Indeed, this year’s report of record-efficiency electrically driven QLEDs rivaling the most efficient molecular organic LEDs, together with the emergence of full-color QLED displays, foreshadow QD technologies that will transcend the optically excited QD-enhanced products already available. In this article, we discuss the key advantages of using QDs as luminophores in LEDs and outline the 19-year evolution of four types of QLEDs that have seen efficiencies rise from less than 0.01% to 18%. With an emphasis on the latest advances, we identify the key scientific and technological challenges facing the commercialization of QLEDs. A quantitative analysis, based on published small-scale synthetic procedures, allows us to estimate the material costs of QDs typical in light-emitting applications when produced in large quantities and to assess their commercial viability.National Science Foundation (U.S.) (Graduate Research Fellowship)United States. Dept. of Energy (Center for Excitonics, an Energy Frontier Research Center funded by the Office of Basic Energy Sciences, under Award Number DE-SC0001088