Department of Chemistry and Biochemistry , University of South Carolina , Columbia , South Carolina 29208 , United States.
Light Technology Institute (LTI) , Karlsruhe Institute of Technology , Engesserstrasse 13 , 76131 Karlsruhe , Germany.
ACS Appl Mater Interfaces. 2018 Aug 1;10(30):25754-25762. doi: 10.1021/acsami.8b05568. Epub 2018 Jul 20.
Organic chromophores that exhibit aggregation-induced emission (AIE) are of interest for applications in displays, lighting, and sensing, because they can maintain efficient emission at high molecular concentrations in the solid state. Such advantages over conventional chromophores could allow thinner conversion layers of AIE chromophores to be realized, with benefits in terms of the efficiency of the optical outcoupling, thermal management, and response times. However, it is difficult to create large-area optical quality thin films of efficiently performing AIE chromophores. Here, we demonstrate that this can be achieved by using a surface-anchored metal-organic framework (SURMOF) thin film coating as a host substrate, into which the tetraphenylethylene (TPE)-based AIE chromophore can be printed. We demonstrate that the SURMOF constrains the AIE-chromophore molecular conformation, affording efficient performance even at low loading densities in the SURMOF. As the loading density of the AIE chromophore in the SURMOF is increased, its absorption and emission spectra are tuned due to increased interaction between AIE molecules, but the high photoluminescent quantum yield (PLQY = 50% for this AIE chromophore) is maintained. Lastly, we demonstrate that patterns of the AIE chromophore with 70 μm feature sizes can be easily created by inkjet printing onto the SURMOF substrate. These results foreshadow novel possibilities for the creation of patterned phosphor thin films utilizing AIE chromophores for display or lighting applications.
具有聚集诱导发光（AIE）特性的有机发色团在显示、照明和传感等领域具有应用前景，因为它们可以在固态下保持高浓度分子时的高效发光。与传统发色团相比，这些优势可以实现更薄的 AIE 发色团转换层，从而提高光学外耦合效率、热管理和响应时间。然而，很难制备出大面积具有光学质量的高效 AIE 发色团薄膜。在这里，我们证明可以使用表面锚定的金属有机骨架（SURMOF）薄膜涂层作为主体衬底来实现这一目标，将基于四苯乙烯（TPE）的 AIE 发色团印刷到该衬底上。我们证明，SURMOF 限制了 AIE-发色团分子构象，即使在 SURMOF 中的低负载密度下也能提供高效性能。随着 AIE 发色团在 SURMOF 中的负载密度增加，由于 AIE 分子之间相互作用的增加，其吸收和发射光谱会发生调谐，但高荧光量子产率（对于这种 AIE 发色团为 50%）得以保持。最后，我们证明可以通过喷墨打印将 AIE 发色团图案轻松地打印到 SURMOF 基底上，其特征尺寸为 70 μm。这些结果预示着利用 AIE 发色团为显示或照明应用创建图案化磷光体薄膜的新可能性。
