CAREER:Engineering Efficient, Thin-film Hybrid Photovoltaic Elements Based on Excitonic Energy Transfer

这项研究的目标是设计一种新型超薄、灵活、高效且坚固的光伏太阳能电池。该方法是采用溶液处理的半导体纳米晶体，化学接枝在电访问，灵活的硅纳米柱p-i-n结substrate.Intellectual优点：这些新型的混合型太阳能电池的设计是基于非辐射和辐射能量转移，这提供了高吸收纳米晶体和3-dimensionally结构的薄硅基板之间的有效的电磁耦合。这种较长范围的能量转移机制基本上避免了导致传统体异质结几何形状的较低效率的典型电荷转移问题。具有工程化能量转移相互作用的光学厚多层膜将接枝在由薄Si衬底加工的纳米柱的密集阵列上，该纳米柱具有增强的光捕获能力和优化的p-i-n结，用于有效的电荷分离和传输。这种纳米晶敏化硅太阳能电池预计将达到15%的转换效率与最低的硅材料的要求。更广泛的影响：薄，但有效的光伏元件的发展应有助于减少我们对化石燃料的依赖，并有助于国内，生态友好和可再生能源发电技术和产业的发展。混合光电子结构将对各种发光和传感器应用感兴趣，这种跨学科的方法将为学生提供机会，使他们能够熟练掌握光子学，材料科学与工程和物理学领域，并与工业项目和国际合作者建立联系。将大力吸引本科生和大学预科生参与，促进他们对科学和工程的兴趣。

The objective of this research is to engineer a new type of ultra-thin, flexible, yet efficient and robust photovoltaic solar cell. The approach is to employ solution processable semiconductor nanocrystals that are chemically grafted on electrically accessible, flexible Si nanopillar p-i-n junction substrates.Intellectual merit: The design of these novel hybrid solar cells is based on non-radiative and radiative energy transfer, which provides efficient electromagnetic coupling between highly absorbing nanocrystals and 3-dimensionally structured thin Si substrates. Such longer-range energy transfer mechanisms essentially avoid typical charge transfer problems leading to lower efficiencies of traditional bulk-heterojunction geometries. Optically thick nanocrystal multilayers with engineered energy transfer interactions will be grafted on dense arrays of nanopillars processed from thin Si substrates with enhanced light trapping capabilities and optimized p-i-n junctions for efficient charge separation and transport. Such nanocrystal-sensitized Si solar cells are expected to reach 15% conversion efficiency with minimal Si material requirements.Broader impacts: The development of thin, yet efficient photovoltaic elements should assist in lessening our reliance on fossil fuels and contribute towards the development of domestic, eco-friendly and renewable energy-generating technologies and industries. Hybrid optoelectronics structures will be of interest for various light-emitting and sensor applications and such interdisciplinary approach will provide students with an opportunity to gain proficiency in the fields of photonics, materials science and engineering and physics and to connect to industrial projects and international collaborators. Strong effort will be devoted to involve undergraduate and pre-college students and facilitate their interest in science and engineering.