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，无论是在屋顶还是在大型太阳能发电站。太阳能电池无需电线就能提供成本效益高的电力，因此适用于“离网”应用。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索的航天器的主要动力来源。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300华氏度的地方传统上都被认为是禁区。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。与太阳能机器人探测器广泛探索的火星相比，我们对金星和水星这两个非常热的近邻所知甚少。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来推进新兴的高温太阳能电池领域，这些设计可以在800华氏度以上的温度下实现高效率。基于镓和铟等第三族元素氮化物的太阳能电池显示出随着温度升高效率的不寻常增加。这为在高温下工作的高效太阳能电池开辟了可能性。除了上述应用之外，该项目还可能导致传感器在苛刻的环境中有效地无线运行，例如发动机。这两个联合PI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生课程，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的目标是使用晶圆键合将III-V和III-N材料的独特优势联合收割机结合起来，形成针对300- 450 C高温优化的多结器件。内太阳系探测和光热混合能源系统需要高温太阳能电池。III-V太阳能电池表现出最高的已知效率，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效率随着温度升高而增加的不寻常特性。这两个合作PI将采取跨学科的方法来展示高温下的高效光致发光，结合外延生长，材料表征，器件制造，器件测试和建模。该项目将促进对高工作温度下光电器件性能的理解。在低温下，热能对电子发射和辐射复合等现象的影响已经得到了广泛的研究，但对300- 450 ℃的高温关注较少。联合PI假设光电设备可以重新设计，以解决，在某些情况下，利用这种高温。这个奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

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.