EAGER: Interface Engineering for Low-Temperature Process and Stable Organometal Perovskite Solar Cells

光伏（PV）技术是将可持续的太阳能转化为电能的一种很有前途的方法。为了进一步降低太阳能电力的成本，提高太阳能电池的效率以及因此提高太阳能电池模块的效率变得更加关键，因为可以通过安装更少的模块来达到相同的功率目标。最近，有机金属卤化物钙钛矿作为有前途的PV材料引起了相当大的关注，因为其单结记录效率快速增加到超过20%，其简单的器件结构，以及在柔性衬底上进行卷对卷低成本制造的可能性。然而，对于基于有机金属卤化物钙钛矿的太阳能电池来说，通过低温制造工艺和长期太阳能电池稳定性实现高性能仍然具有挑战性。该研究项目旨在获得基础知识，以支持发现新的太阳能电池界面材料，这些材料对水分和空气具有更大的稳定性，同时保持高效率。该项目还为来自清洁能源联盟的新生提供研究机会，为代表性不足的美国人提供学习和愿景（阿尔瓦）计划，并利用研究成果为介绍一个女孩到光子博览会的推广计划。从这些材料中获得的基础知识将对光电子学、光电子学和新半导体材料领域产生重大影响。本研究项目的目的是研究新的空穴传输层（HTL）材料，通过引入内部偶极子和操纵钙钛矿薄膜的形态来提高钙钛矿太阳能电池的性能和稳定性。新的HTL材料利用聚（3，4-乙撑二氧噻吩）（PEDOT）作为空穴传输主链，而不同的官能团侧链提供形成偶极子，可以修改能带能量排列。通过改变HTL结构的能带能量排列和钙钛矿层的形态，假设将导致电荷传输和收集以及器件稳定性的改善。目前正在合成基于PEDOT的HTL材料，并研究低温下制备的HTL薄膜的电学、光学和结构特性。新的基于PEDOT的HTL正被部署在平面p-i-n结构的钙钛矿太阳能电池中，器件性能和稳定性正在测试中。有机金属卤化物钙钛矿表现出宽范围的带隙，使得能够制造高效的单结和串联太阳能电池。该研究项目可以改变光伏技术，并使钙钛矿基光伏技术以具有竞争力的低成本商业化成为可能。

Photovoltaic (PV) technology is a promising method to convert sustainable solar energy into electricity. In order to further lower the cost of solar electricity, increasing efficiency of solar cells, and therefore solar cell modules, becomes more critical because the same power target can be reached with the installation of fewer modules. Recently, organometal halide perovskites have attracted considerable attention as promising PV materials because of the rapid increase in single-junction record efficiencies to exceed 20%, their simple device structures, and the possibility for roll-to-roll low-cost manufacturing on flexible substrates. However, achieving high performance via a low-temperature manufacture process and long-term solar cell stability is still challenging for solar cells based on organometal halide perovskites. This research project seeks to gain fundamental knowledge supporting the discovery of new solar cell interface materials that will have greater stability towards moisture and air while retaining high efficiency. The project is also providing research opportunities for freshmen from the Clean Energy Alliances for Learning and Vision for Underrepresented Americans (ALVA) program and leveraging the research results for the outreach program of Introduce A Girl to Photonics Fair. The fundamental knowledge gained from these materials will make significant impacts on the fields of photovoltaics, optoelectronics and new semiconductor materials. The objective of this research project is to research new hole transport layer (HTL) materials to improve the performance and stability of perovskite solar cells by introducing internal dipoles and by manipulating the morphology of perovskite films. The new HTL materials utilize poly (3, 4-ethylenedioxythiophene) (PEDOT) as a hole transport backbone while different functional group side chains offer to form dipole that could modify the band energy alignment. By modifying the band energy alignment of the HTL structure and the morphology of the perovskite layers, it is hypothesized that an improvement in charge transport and collection as well as device stability will result. The PEDOT-based HTL materials are being synthesized and the electronic, optical and structural properties of HTL thin films fabricated at low temperatures are being investigated. The new PEDOT-based HTLs are being deployed in planar p-i-n structure perovskite solar cells and the device performance and stability are being tested. Organometal halide perovskites exhibit a broad range of band gap enabling the possibility to make highly efficient single-junction and tandem solar cells. This research project could transform photovoltaic technology and make it possible to commercialize perovskite-based photovoltaic technology with competitively low cost.