Materials World Network: Intermediate Band Semiconductor Materials for High Efficiency Solar Energy Conversion

这个材料世界网络的重点是通过II-VI-O化合物半导体的中间电子态进行有效的太阳能转换，这是由密歇根大学（美国）和马德里politcnica大学（西班牙）太阳能能源研究所的研究人员合作完成的。半导体材料带隙中的中间态提供多个光学跃迁和相应的光学吸收带。基于这些材料的太阳能电池装置提供了一种潜在的高效途径，使用在简化的单结结构中具有三个确定的吸收带的材料。在II-VI化合物半导体中引入氧等电子杂质，有望实现具有高辐射效率和与太阳光谱相匹配的能量位置的光学跃迁。虽然这些材料非常适合高效的太阳能转换，但需要在材料合成和对光电特性的理解方面取得重大进展。该项目的主要技术目标是1)II-VI材料中氧态的理论和实验研究，2)II-VI- o材料中多光子光学跃迁的表征，以及3)通过中间电子态中载流子输运的确定。中间带材料的研究将直接影响光伏太阳能电池技术，其中预期的高效率和简单的单结器件设计将降低太阳能转换的成本。该项目将通过资助国外研究、科学家交流和建立一系列研讨会来促进研究生的教育。这一合作关系还将加强密歇根大学现有的教育工作，在那里，光伏和太阳能系统工程100课程的大一新生将与一家领先的太阳能研究所建立联系，作为他们团队项目的一部分，设计和实施一个由太阳能供电的系统。该项目由材料研究部（DMR）和NSF国际科学与工程办公室（OISE）共同资助。

This Materials World Network focuses on efficient solar energy conversion via intermediate electronic states in II-VI-O compound semiconductors in collaboration between researchers at The University of Michigan (US) and the Instituto de Energia Solar at the Universidad Politécnica de Madrid (Spain). Intermediate states in the bandgap of a semiconductor material provide multiple optical transitions and corresponding optical absorption bands. Solar cell devices based on these materials offer a potential route to high efficiency using a material with three defined absorption bands in a simplified one-junction structure. The introduction of oxygen isoelectronic impurities in II-VI compound semiconductors show promise in realizing optical transitions with high radiative efficiency and energetic positions well matched to the solar spectrum. While these materials are well suited for highly efficient solar energy conversion, major advances in material synthesis and the understanding of optoelectronic properties are required. The primary technical objectives of this project are 1) the theoretical and experimental study of oxygen states in II-VI materials, 2) characterization of multi-photon optical transitions in II-VI-O materials, and 3) determination of charge carrier transport in via intermediate electron states.Research on intermediate band materials will directly impact photovoltaic solar cell technology, where the projected high efficiency and simplistic single-junction device design would lower the cost of solar energy conversion. This project will contribute to the education of graduate students by funding research abroad, exchange of scientists, and the establishment of a seminar series. The partnership will also enhance existing educational efforts at the University of Michigan, where freshman in the Engineering 100 course on photovoltaics and solar-powered systems will have a connection to a leading solar energy institute as a part of their team project to design and implement a system powered by solar energy.This project is jointly funded by Division of Materials Research (DMR) and the NSF Office of International Science and Engineering (OISE).