Organic electroluminescent device comprising two-dimensional emissive layer
摘要
說明書
In addition to the spectral shift, the radiative decay rate of trions are less than 5 times that of the excitons, resulting in a reduction in mWS2 photoluminescence intensity as a function of injected electron density in
A light emitting device was demonstrated with an active layer comprising a CVD grown, large-area mWS2 as the luminescent material, combined with organic buffer layers (charge transport and host matrix layers) that enable efficient charge transport and exciton generation. The use of mWS2 enables principally horizontally aligned transition dipole moments and fast exciton decay leading to enhanced outcoupling and device stability. Moreover, the organic host was used to efficiently generate and inject excitons into the mWS2 via F?rster transfer. Thus, the mWS2 was positioned several nanometers distant from the heterointerface which prevented sites for non-radiative recombination and leads to morphological instabilities. LEDs with diameters of 250 μm exhibited average EQE=0.3±0.3% with a peak of 1%. In addition, electron- and hole-only-devices indicated that the injected electrons in mWS2 combine with excitons generating trions, reducing EQE at high current densities. The results show an efficient way of incorporating promising luminescent materials into an organic device structure.
