基于硅量子点的有机/无机杂化太阳电池制备及其性能改善的机理和实验研究

Silicon quantum dots (Si QDs) based organic/inorganic hybrid solar cells remain the superiorities of organic solar cells, moreover, advantages of Si QDs have also been introduced. Recently, they have attracted more attention and been studied extensively. However, several problems related to device structure, material quality and fabrication process have prohibited the further promotion of device performance. In this project, we plan to explain the device working principle and figure out the energy loss mechanism. Meanwhile, we expect the substantial improvement of solar cell efficiency through several strategies. We will try to suppress carrier trapping and recombination on Si QDs surface through passivation of dangling bonds with inorganic elements; improve device light absorption, optimize band alignment and carrier mobility matching through exploration of high performance polymers; enhance carrier transportation and collection through fabrication of electron transporting layers; and suppress energy loss due to thermal relaxation by changing Si QDs size and introduction of quantum effects. Finally, as the results of substantially enhanced short circuit current, open circuit voltage and fill factor, dramatic promotion of solar cell efficiency from 3.6% to above 10% can be expected. Furthermore, we will try to realize the practical application of Si QDs based hybrid solar cells. We also aim to propose a new approach towards high efficiency solar cells. This work will also promote the vast applications of Si QDs in optoelectronic devices, and provide valuable knowledge to related research fields.

基于硅量子点的有机/无机杂化太阳电池在保持有机电池优势的基础上兼具硅量子点的优点，近年来得到了广泛关注和快速发展。然而目前在电池结构、材料及制备工艺上存在的问题制约了电池性能的提升。本项目旨在揭示电池工作原理及能量损失机制的同时，进一步提高电池效率。该工作将开创性地利用无机元素表面修饰来有效抑制光生载流子在硅量子点表面悬挂键上的捕获和复合，探索使用高性能有机材料来提高电池光吸收并优化电池能带及载流子迁移率的匹配，尝试制备新型电子传输层来促进载流子的传输与收集，系统改变硅量子点尺寸并引入量子尺寸效应来抑制光生载流子热弛豫导致的能量损失。从而在大幅改善电池短路电流、开启电压及填充因子的前提下实现电池效率从目前3.6%到10%以上的提升。该项目的研究不仅使硅量子点杂化电池的实用化成为可能，也为发展高效率电池开辟新的方向。另外还将推动硅量子点在光电器件中的广泛应用, 并为相关研究提供有价值的参考。

利用甚高频非热大气压等离子体技术，利用较为安全的四氯化硅作为反应前驱，通过调节各种工艺参数制备了具有不同性能的硅量子点；提出了切实可行的硅量子点表面钝化技术，实现了硅量子点光电性能的提升；制备了一系列基于硅量子点的有机无机杂化太阳电池，通过优化制备工艺、设计新结构、利用新原理，获得了效率高达~17%的高性能太阳电池；本研究也在一定程度上推动了硅量子点在光电器件中的广泛应用，并为今后相关领域的研究提供了较为有价值的参考。