Polymer photonic devices based on mixed ionic/electronic conductors: device and materials physics

基于混合离子/电子导体的聚合物光子器件：器件和材料物理

• 批准号: RGPIN-2015-05344
• 负责人: Gao, Jun
• 金额: $ 1.6万
• 依托单位: Queen's University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=613497
• 关键词: Polymer; photonic; devices; based; mixed

Semiconductor photonic devices such as light-emitting diodes (LEDs), solar cells, photodiodes, and diode lasers are indispensible in our technology- and information-driven world. While these devices are still mainly based on silicon or group III-V compounds, various organic semiconductors have emerged as potential candidates for next-generation applications that require even higher functionality and less energy consumption. Semiconducting polymers are especially attractive because they have the mechanical and processing advantages of polymeric materials as well as being optically and electrically interesting. To make “plastic electronics” a reality, polymer semiconductors need to be better understood and fully exploited not only in their pure form, but also when “doped.” The field of “conductive polymers” (2000 Nobel Prize in Chemistry) came into existence when polyacetylene was discovered to exhibit vastly improved conductivity when chemically doped. Most polymer devices to date are based on pristine polymers. An exception is the polymer light-emitting electrochemical cell (LEC), whose active layer is a mixed ionic/electronic conductor (MIEC). The MIEC of an LEC is electrochemically doped in situ during operation, and a light-emitting p-n or p-i-n junction is formed between the differently doped regions. The LECs possess many desirable device characteristics as a result of doping. The chief challenges facing MIEC devices such as LECs is their inferior operational lifetime and the lack of understanding of the underlying physics. This is in large part due to the complex nature of MIEC devices, which possess at least four different charge carriers that can interact. In our proposed research, various polymer MIEC devices will be explored and investigated in depth in order to deal with the challenges. In particular, we will perform unprecedented, concerted scanning photocurrent, photoluminescence and absorption measurements of extremely large, frozen planar cells in order to better understand the electronic structure of MIEC junctions.  In addition, we strive to achieve long lasting MIEC devices ready for practical applications. The proposed research will build on my group’s extensive experience working on MIEC light-emitting cells and photovoltaic cells that has resulted in nearly 30 publications in top international journals in recent years. My group also developed a suite of powerful experimental techniques ideally suited for the study of MIEC devices. These include time-lapse fluorescence imaging, frozen-junction and controlled junction relaxation, scanning electrical probing of conductivity and electric potential, and concerted scanning photocurrent and photoluminescence probing techniques. The proposed research offers excellent opportunities for the training of HQPs that will prepare them for a career in academic research or industrial R&D.

发光二极管 (LED)、太阳能电池、光电二极管和二极管激光器等半导体光子器件在我们这个技术和信息驱动的世界中是不可或缺的，尽管这些器件仍然主要基于硅或 III-V 族化合物，但它们的种类繁多。有机半导体已成为需要更高功能和更少能耗的下一代应用的潜在候选者。半导体聚合物特别有吸引力，因为它们具有聚合物材料的机械和加工优势。光学和电学方面都很有趣。 为了使“塑料电子”成为现实，需要更好地理解和充分利用聚合物半导体，不仅是其纯净形式，而且是“掺杂”形式。“导电聚合物”领域（2000 年诺贝尔化学奖）应运而生。迄今为止，大多数聚合物器件都基于原始聚合物，但聚合物发光电化学电池 (LEC) 被发现具有显着改善的电导率，其活性层是聚乙炔。 LEC 的 MIEC 在运行过程中进行原位电化学掺杂，并且在不同掺杂区域之间形成发光 p-n 或 p-i-n 结，因此 LEC 具有许多理想的器件特性。 MIEC 器件（例如 LEC）面临的主要挑战是其使用寿命较短以及缺乏对基础物理的了解，这在很大程度上是由于 MIEC 器件的复杂性所致。至少有四种可以相互作用的不同电荷载体。 在我们提出的研究中，将深入探索和研究各种聚合物 MIEC 装置，以应对挑战。特别是，我们将对极大的冷冻平面电池进行前所未有的协同扫描光电流、光致发光和吸收测量。更好地了解 MIEC 结的电子结构。此外，我们致力于实现可用于实际应用的持久 MIEC 器件。拟议的研究将建立在我的团队在 MIEC 发光电池和光伏电池方面的丰富经验的基础上。近年来，我的团队在顶级国际期刊上发表了近 30 篇论文，还开发了一套非常适合 MIEC 器件研究的强大实验技术，其中包括延时荧光成像、冷冻结和受控结弛豫、扫描电探测。拟议的研究为 HQP 的培训提供了绝佳的机会，为他们从事学术研究或工业研发做好准备。