Exciton-induced Degradation of Interfaces in Organic Optoelectronic Devices

在过去的二十年里，人们对基于有机半导体的光电器件产生了浓厚的兴趣，这些器件用于各种应用，包括固态照明、平板显示器和太阳能电池。这种兴趣是由有机半导体具有的许多关键优势所激发的，例如(i)可以获得各种颜色的光发射；（ii）更容易和更便宜的制造，包括在不同的衬底和大面积上制造它们的能力；（iii）它们为下一代电子产品实现机械柔性和透明设备的独特能力。尽管具有这些优点，但与基于传统材料的器件相比，使用这些材料的器件，例如有机发光器件（oled），有机太阳能电池（OSCs）通常具有较低的耐用性。我们最近发现，暴露在光下，无论是外部光源，如OSCs，还是设备本身产生的光，如oled，都会导致这些设备发生重大变化，特别是在不同材料之间的界面上。这种以前未知的现象似乎是这些设备效率迅速下降的原因。

The last two decades have witnessed a strong interest in organic semiconductor-based optoelectronic devices for utilization in various applications including solid state lighting, flat panel displays and solar cells. This interest is motivated by a number of key advantages that organic semiconductors have, such as (i) the possibility to obtain light emission in a wide range of colors (ii) easier and cheaper fabrication including the ability to fabricate them on different substrates and in large areas, and (iii) their unique ability to realize mechanically flexible and transparent devices for next generation electronics. Despite their advantages, devices utilizing these materials, such as Organic Light Emitting Devices (OLEDs), Organic Solar Cells (OSCs) generally have lower durability in comparison to those based on traditional materials. We recently discovered that exposure to light, either from external sources, as in case of OSCs, or to light produced by the device itself, as in case of OLEDs, causes significant changes in these devices, especially at interfaces between different materials. This previously unknown phenomenon appears to be responsible for the fast deterioration in efficiency in these devices. The proposed research aims to uncover the factors behind this phenomenon and to develop approaches to control them, thus improve device service life. The research will utilize a number of experimental techniques pioneered by the applicant and will build on findings from his previous work in this area. Seven graduate students will participate in this research. The research results will be critical for future development of more stable OLEDs and OSCs, which will be pursued in collaboration with Canadian industrial partners. It will, therefore, provide those partners with a competitive edge in an emerging technology of tremendous potential for next generation electronics and energy conversion devices. The research will also allow training of a new “breed” of Canadian researchers who will acquire expertise in an emerging technology that has the potential to enable new products and market opportunities.