Frequency-Selective Photobleaching as a Route to Chromatic Control in Supramolecular OLED Devices

Abstract

We report a series of molecules that spontaneously self-organize into small electroluminescent domains of sub-micrometer dimensions when dissolved in tetrahydrofuran. The self-assembled spherical aggregates have an average diameter of 300 nm and exhibit efficient energy transfer from the blue to the green or red component. The aggregates can be chromatically addressed or patterned by selective bleaching of the energy-acceptor component using a laser source. This allows the fabrication of electroluminescence devices by directly photopatterning the active layer without the need of additional steps. Submicron features (700 nm) can be achieved using a collimated light source.

Incorporation of narcissistic self-sorting supramolecular interactions for the spontaneous fabrication of multiple-color solid-state materials for OLED applications

“…The resulting drop-or spin-cast materials possess narrow colour distributions, implying that the dispersion of the components is homogeneous between aggregates. Simultaneously obtaining aggregates of different colours in a single device is therefore not directly possible using this approach and requires either the sequential deposition of the different colours 42,43 or the use of a colour-bleaching technique 44 to subsequently tune the emission profile of the material. Although the size of the rigid, p-conjugated core does not seem to have a strong effect on the formation of the vesiclelike aggregates, we remarked that this is not the case for the orientation of the biuret molecular recognition motifs.…”

“…The synthesis of compounds 1-3 in their para-and meta-series through Suzuki cross-coupling of 3-or 4-biuretphenylboronic acid with the corresponding aromatic core was described previously. 40,44 Both series of compounds spontaneously generate vesicle-like aggregates upon dissolution in anhydrous THF (10 À4 M concentration) that, upon deposition on conductive substrates, allows the systematic fabrication of OLED devices emitting in the blue, green, and red regions of the visible spectrum. 42,44 Dynamic and static light scattering experiments, and small angle X-ray diffraction are consistent with the presence, in solution, of hollow sphere aggregates possessing a thin (ca.…”

“…40,44 Both series of compounds spontaneously generate vesicle-like aggregates upon dissolution in anhydrous THF (10 À4 M concentration) that, upon deposition on conductive substrates, allows the systematic fabrication of OLED devices emitting in the blue, green, and red regions of the visible spectrum. 42,44 Dynamic and static light scattering experiments, and small angle X-ray diffraction are consistent with the presence, in solution, of hollow sphere aggregates possessing a thin (ca. 30 nm) shell that are subject to Brownian motion (i.e.…”

Supramolecular gating of TADF process in self-assembled nano-spheres for high-resolution OLED applications

“…14,15 These are preserved upon drop-casting or spin-coating to generate individual pixels which can allow novel material properties, such as spontaneous self-sorting of different colors 16 and frequency-selective photobleaching. 17 Furthermore, we showed that individual spheres of each of the three primary colors could be deposited in very close proximity without bleeding or cross-contamination thanks to the pre-assembled supramolecular architectures. 14 These form pixels whose sub-micron size can, in principle, allow RGB resolutions attaining 20 000 dpi.…”