Organometal Halide Perovskites: Sequential Vapor Deposition And Device Study Toward Highly Efficient Thin-Film Solar Cells

主要研究者：范朝阳编号：1438681太阳代表着地球上最丰富的潜在无污染能源。 用于发电的太阳能电池需要吸收太阳能并将其光子转化为电子的材料，这一过程称为光电子学。 寻找最佳光伏材料是太阳能电池研究的一个活跃领域。 最近，出现了一类令人兴奋的新型光伏材料，称为有机金属钙钛矿。这些材料很有前途，因为它们生产成本低，使用地壳中丰富的元素和材料，目前拥有超过15%的太阳能转换效率。 基于Peroxide的太阳能材料必须被浇铸成非常薄的膜，以用于光化学。 提高这些材料的太阳能转换效率的根本挑战是制造无缺陷的晶体薄膜。 该项目的目标是通过一种新的化学气相沉积工艺制造均匀、高度结晶、无针孔的薄膜，以达到20%以上的效率。 在这个过程中，用于制造钙钛矿的化学材料以规定的顺序添加到腔室中处于气态，然后允许在限定的温度下在表面上反应。 本项目将开发这一工艺，并研究钙钛矿薄膜的材料和光伏特性。 在教育活动方面，该项目将在太阳能电池材料和设备开发的基本方面培训两名博士生和几名本科生，这些领域对美国在可再生和清洁能源经济中的竞争力至关重要。 太阳能和可再生能源的推广活动也将通过德克萨斯理工大学可持续世界工程师学生分会开展，受过培训的学生将通过该机构的T-STEM中心担任未来K-12推广工作的大使。最近，有机金属钙钛矿已经成为一类令人兴奋的新的地球丰富的光伏材料，太阳能转换效率超过15%，并具有低制造成本的潜力。 本计画的目标是发展一种连续气相沉积法来合成高结晶品质的有机金属卤化物薄膜，并研究其电荷传输与复合过程，以探讨效率瓶颈。 所提出的气相沉积工艺是基于顺序气相传输沉积或顺序真空气相沉积，并且被设计成在保持低成本薄膜制造方案的属性的同时制造均匀和结晶的薄膜。基础材料研究，特别是氯在钙钛矿混合物中的作用，将为材料和器件设计提供知识基础。具体而言，将在钙钛矿材料水平上研究电荷传输和复合，并包括微观尺度映射表征。 将对两个接口进行器件级研究，以提供材料和接口结构设计指南。总之，这种对薄膜合成、光伏材料表征和基于高度结晶钙钛矿的薄膜太阳能电池的器件性能表征研究的综合研究有可能使薄膜太阳能电池技术取得根本性进展。

Principal Investigator: Zhaoyang FanNumber: 1438681 The sun represents the most abundant potential source of pollution-free energy on earth. Solar cells for producing electricity require materials that absorb the sun's energy and convert its photons to electrons, a process called photovoltaics. The search for the best photovoltaic material is an active area of solar cell research. Recently, an exciting new class of photovoltaic materials called organo-metal perovskites has emerged. These materials are promising because they have low production cost, use elements and materials abundant in the earth's crust, and currently possess solar energy conversion efficiencies of over 15%. Perovskite based solar materials must be cast as a very thin film to be active for photovoltaics. A fundamental challenge for improving the solar energy conversion efficiency of these materials to is make crystalline thin films that are free of defects. The goal of this project is to make uniform, highly crystalline, and pin-hole free films designed to achieve efficiencies over 20% through a new chemical vapor deposition process. In this process, the chemical materials used to make the perovskites are added a chamber is a gaseous state in a prescribed sequence and then allowed to react on a surface at defined temperatures. This project will develop this process and study the material and photovoltaic properties of the perovskite thin films. With respect to educational activities, this project will train two PhD students and several undergraduate students in the fundamental aspects of solar cell material and device development, areas that are essential to the U.S. competitiveness in the renewable and clean energy economy. Outreach activities on solar and renewable energy will be also developed through the Student Chapter of Engineers for a Sustainable World at Texas Tech University, where trained students will serve as ambassadors for future K-12 outreach efforts through the institution's T-STEM Center. Technical DescriptionRecently, organo-metal perovskites have emerged as an exciting new class of earth-abundant photovoltaic materials with solar energy conversion efficiencies exceeding 15% and potential for low manufacturing cost. The goals of this project are to develop a sequential vapor deposition process for synthesis of organometal halide thin films with high crystalline quality, and then study the charge transport and recombination processes to probe for efficiency bottlenecks. The proposed vapor deposition process is based on sequential vapor phase transport deposition or sequential vacuum vapor deposition, and is designed to make uniform and crystalline thin films while maintaining the attributes of low cost thin film manufacturing scheme. Fundamental material studies, particularly the role of chlorine in the perovskite mixture, will provide knowledge basis for material and device design. Specifically, charge transport and recombination will be studied at the perovskite material level, and include micro-scale mapping characterization. Device level studies with two interface junctions will be performed to provide guidelines on material and interface structure design. Together, this integrated investigation of thin film synthesis, photovoltaic material characterization, and device performance characterization studies for highly crystalline perovskite based thin film solar cells has the potential to make fundamental advances in thin film solar cell technology.