Bulk Heterostructure Solar Cells: Electronic Structure and Interface Design

技术：本研究项目的主要重点是确定基于纳米颗粒、聚合物、染料和小分子材料的共混物和薄膜的三维异质结构激子太阳能电池的电子结构。这种太阳能电池有望降低生产成本，同时提供低重量和机械灵活性。太阳能电池中材料界面的电子结构对激子解离、防止复合和电荷转移至关重要。为了进一步提高效率和开路电压，有必要了解这些接口的电子结构。本项目采用的主要分析技术包括光发射光谱和逆光发射光谱，它们可以直接测量分子异质界面上的电荷注入势垒。这些实验的制备技术是真空电喷雾沉积，这是近年来在PI小组的努力下建立起来的。这种独特的光发射光谱、逆光发射光谱和电喷雾沉积在同一实验系统中的组合，可以同时表征大分子界面上的占据和未占据状态。此外，本项目还研究了在常压下使用电喷雾沉积技术制备太阳能电池结构的可行性。静电为控制沉积膜的微观形貌提供了途径。非技术：该项目涉及材料科学主题领域的基础研究问题，具有高技术相关性。该研究项目旨在提高人们对基于有机材料和纳米颗粒的异质结太阳能电池的认识，同时寻求一种新的太阳能电池制造方法。在教育方面，研究生和本科生在参与战略重要领域的前沿科学研究的同时得到培养。PI特别注重为这个研究项目招募少数民族和女学生，并且在让本科生（包括那些代表性不足的群体的学生）参与研究方面有着良好的记录。

Technical: The main focus of this research project is on the determination of the electronic structure of three-dimensional heterostructure excitonic solar cells based on blends and thin films of nanoparticles, polymers, dyes and small molecular materials. Such solar cells promise low production costs, while offering low weight and mechanical flexibility. The electronic structure of materials interfaces in the solar cells is crucial for exciton dissociation, recombination prevention, and charge transfer. In order to further increase efficiency and open circuit voltage, it is essential to understand the electronic structure of these interfaces. The main analytical techniques employed in this project include photoemission and inverse photoemission spectroscopies, which allow the direct measurement of charge injection barriers at molecular heterointerfaces. The enabling preparative technique for these experiments is in-vacuum electrospray deposition, which has been established in recent years through previous efforts in the PI's group. This unique combination of photoemission spectroscopy, inverse photoemission spectroscopy, and electrospray deposition in the same experimental system allows the characterization of occupied and unoccupied states at macro-molecular interfaces at the same time. Additionally, feasibility of spray-based fabrication of solar cell structures using the electrospray deposition at atmospheric pressure is investigated in this project. The electrostatics offers ways for controlling the microscopic morphology of deposited films.Non-technical: The project addresses basic research issues in a topical area of materials science with high technological relevance. The research project aims to improve the understanding of heterojunction solar cells based on organic materials and nanoparticles and at the same time seeks a new method for solar cell fabrication. On the educational side, graduate and undergraduate students are trained while participating in the cutting-edge scientific research of a strategically important area. The PI especially focuses on recruiting minority and female students for this research project and has an established record of involving undergraduate students, including those from the underrepresented groups, in research.