Understanding Multiple Exciton Generation and Charge Extraction in All-Inorganic Nanostructured Solar Cells from first principles

从第一原理了解全无机纳米结构太阳能电池中的多重激子产生和电荷提取

• 批准号: 211374683
• 负责人: Dr. Stefan Martin Wippermann
• 金额: --
• 依托单位: Abteilung Grenzflächenchemie und Oberflächentechnik
• 依托单位国家: 德国
• 项目类别: Research Fellowships
• 财政年份: 2012
• 资助国家: 德国
• 起止时间: 2011-12-31 至 2012-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/211374683?language=en
• 关键词: Understanding; Multiple; Exciton; Generation; Charge

This proposal investigates a transformative new paradigm of solar energy conversion:1. a high efficiency Multiple Exciton Generation (MEG) pathway2. the corresponding challenge of charge extraction3. in all-inorganic nanostructured solar cellsMEG was recently observed in nanoparticles (NPs) and is not subject to the 31% theoretical solar energy conversion limit. It is planned to utilize density functional theory based methods to explore systematically the MEG and charge extraction processes in Si and Ge NP-based all-inorganic solar cells, with focus on the NP surfaces and charge transport. The applicant wants to answer the following questions related to:1. Competing MEG theoriesAt present there are three competing theories to account for the MEG being enhanced so much over its small bulk value. Which is the correct one? Calculating the NP spectra including exciton-exciton interaction within the three different frameworks will allow a comparison with experimental studies, in an attempt to identify the ultimately correct theory of MEG.2. NP surface effectsHow do NP surface reconstruction and passivation influence the electronicstructure and spectra of the NPs? How does it influence the charge transport? How should the surface passivation be chosen to optimize the competing design requirements of preserving quantum confinement in support of the MEG process, while still ensuring a strong enough coupling for charge extraction?3. NP-NP couplingIn realistic solar cell architectures the NPs are relatively close to each other. Towhat extent does the electronic coupling between NPs influence their spectra? How does the NP-NP separation influence the charge extraction?Ideally, this project will not only lead to a thorough understanding of the MEG process in nanoparticles, but should allow for qualitative predictions about how to optimize the efficiency of both the MEG and charge extraction processes in realistic solar cell applications.

该提案研究了太阳能转换的变革性新范式：1。高效率的多激子产生（MEG）途径2.电荷提取的相应挑战3.在全无机纳米结构太阳能电池中最近在纳米颗粒（NP）中观察到MEG，并且不受31%的理论太阳能转换限制。计划利用基于密度泛函理论的方法系统地探索Si和Ge NP基全无机太阳能电池中的MEG和电荷提取过程，重点关注NP表面和电荷传输。申请人希望回答以下相关问题：1.竞争的MEG理论目前有三个竞争的理论来解释MEG被增强了这么多，超过了它的小体积值。哪个是正确的？计算NP光谱，包括激子激子相互作用的三个不同的框架内将允许与实验研究进行比较，试图确定最终正确的理论MEG。NP表面效应NP表面重构和钝化如何影响NP的电子结构和光谱？它如何影响电荷输运？应该如何选择表面钝化来优化保持量子限制以支持MEG过程的竞争设计要求，同时仍然确保足够强的电荷提取耦合？3. NP-NP耦合在实际的太阳能电池架构中，NP彼此相对接近。纳米粒子之间的电子耦合在多大程度上影响它们的光谱？NP-NP分离如何影响电荷提取？理想情况下，该项目不仅将导致对纳米颗粒中MEG过程的透彻理解，而且应该允许对如何在现实的太阳能电池应用中优化MEG和电荷提取过程的效率进行定性预测。