Collaborative Research: InGaN/III-V hybrid integration for high-temperature solar cells

非技术：太阳能电池在世界许多地方越来越普遍，无论是在屋顶上还是在大型太阳能发电站中。太阳能电池在没有电线的情况下提供具有成本效益的电力，因此对“离网”应用很有用。例如，太阳能电池为传感器网络供电并提供便携式电源。它们也是卫星以及用于行星探测的太空飞行器的主要动力源。传统的太阳能电池会随着温度的升高而失去效率。因此，任何温度超过华氏300度的地方传统上都被视为禁区。因此，能够同时利用热能和太阳能的创新发电方案从未实现过。与已经被太阳能机器人广泛探索过的火星相比，我们对非常热的金星和水星的了解少得惊人。太阳能汽车可以改变这一点。该项目旨在通过展示耐用的新设计，在800华氏度以上的温度下实现高效率，推动新兴的高温太阳能电池领域的发展。基于III族元素氮化物（如镓和铟）的太阳能电池，随着温度的升高，效率呈现出不同寻常的提高。这开启了在高温下工作的高效太阳能电池的可能性。除了上述应用之外，该项目还可以使传感器在苛刻的环境（如发动机）中高效无线运行。这两家合作项目将寻求将太阳能电池测试纳入各自机构的教师培训计划。他们还将把研究纳入研究生和本科课程，并继续致力于招募代表性不足的学生进入STEM职业。技术：Lee和Zhao的目标是利用晶圆键合技术将III-V和III-N材料的独特优势结合起来，形成适合300-450℃高温的多结器件。高温太阳能电池是内太阳系探测和光热混合能源系统所需要的。III-V型太阳能电池表现出最高的效率，但其性能随着温度的升高而下降。相比之下，III-N太阳能电池最近表现出了随着温度升高而效率提高的不同寻常的特征。这两家合作项目将采用跨学科的方法，结合外延生长、材料表征、器件制造、器件测试和建模，来展示高温下的高效光伏。该项目将促进对光电器件在高温下性能的理解。在低温下，热能对热离子发射和辐射复合等现象的影响已经得到了广泛的研究，而对300-450℃高温的研究较少。co- pi假设光电器件可以重新设计，以解释并在某些情况下利用这种高温。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Non-technical:Solar cells are increasingly common in many parts of the world, both on rooftops and in large scale solar power stations. Solar cells provide cost-effective power without wires and so are useful for "off-grid" applications. For example, solar cells power sensor networks and provide portable power. They are also the primary power source for satellites, as well as space vehicles used for planetary exploration. Traditional solar cells lose efficiency as temperature increases. Consequently, any place where temperatures exceed 300 degrees Fahrenheit has traditionally been considered off-limits. As a result, innovative power generation schemes that could benefit from the ability to use both heat energy and solar energy at the same time have never been realized. In comparison to Mars, which has been extensively explored by solar-powered robotic vehicles, we know surprisingly little about our very hot nearby neighbors of Venus and Mercury. Solar-powered vehicles could change this. This project aims to advance the burgeoning field of high-temperature solar cells by demonstrating durable new designs that can achieve high efficiency at temperatures above 800 degrees Fahrenheit. Solar cells based on nitrides of Group III elements such as gallium and indium have shown an unusual increase in efficiency with rising temperature. This opens up the possibility of efficient solar cells that operate at high temperature. Beyond the applications above, this project could also lead to sensors that operate efficiently and wirelessly in demanding environments, such as engines. The two co-PIs will seek to incorporate solar cell testing into teacher training programs at their respective institutions. They will also incorporate research into graduate and undergraduate classes and continue their commitment to recruiting under-represented students into STEM careers.Technical:Lee and Zhao aim to combine the unique strengths of III-V and III-N materials using wafer bonding to form multi-junction devices optimized for high temperatures of 300-450C. High-temperature solar cells are needed for inner solar system exploration and hybrid photovoltaic-thermal energy systems. III-V solar cells exhibit the highest-known efficiencies, but their performance decreases with increasing temperature. In contrast, III-N solar cells have recently demonstrated the unusual characteristic of increasing in efficiency with rising temperature. The two co-PIs will take an interdisciplinary approach to demonstrate high-efficiency photovoltaics at high temperature, combining epitaxial growth, materials characterization, device fabrication, device testing, and modeling. This project will advance understanding of optoelectronic device performance at high operating temperatures. The impact of thermal energy on phenomena such as thermionic emission and radiative recombination have widely been studied at cryogenic temperatures, with less attention paid to elevated temperatures of 300-450C. The co-PIs hypothesize that optoelectronic devices can be redesigned to account for and, in some cases, take advantage of such elevated temperatures.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.