CAREER: Lead-Free Pseudohalide/Halide Perovskites for Next-Generation White Light-Emitting Diodes

照明占美国总用电量的八分之一。传统光源如白炽灯泡和荧光灯管消耗大量能源。发光二极管（led）作为新一代照明技术，具有超长的使用寿命和极低的能耗。尽管发展迅速，但LED技术仍处于早期阶段，需要不断创新和突破才能充分发挥这项技术的潜力。白光led通常是通过将黄色发光材料（称为“荧光粉”）涂在蓝色led上而获得的。缺乏红色成分导致冷色，不适合室内照明应用。CAREER项目的目标是开发高效、环保的发光材料，利用地球上丰富的元素和低成本、大规模的基于解决方案的方法来取代黄色荧光粉。该项目旨在开发具有卓越色彩质量的高效白光led，加快白光led的广泛采用，并节省能源。该项目为本科生和研究生提供多学科领域的教育培训，如物理、材料科学、电气工程和机械工程。该研究还与当地K-12学校的光子教育活动相结合。该项目由材料研究部和促进竞争研究的既定计划（EPSCoR）共同资助。金属卤化物钙钛矿是一种很有前途的半导体材料，在光电器件中具有潜在的应用前景。然而，这种材料普遍包含铅和稳定性问题阻碍了这些材料的实际应用。首席研究员正在探索新的无铅假卤化物/卤化物钙钛矿纳米晶体，并通过理论和实验方法研究影响其光学性质和稳定性的因素。在这个项目中获得的知识提高了我们对伪卤化物/卤化物钙钛矿材料物理的基本理解，并有助于发现下一代白光led的新环保材料。该项目希望解决这些材料实际应用中的难题，并加速其在光电器件中的应用。该项目的完成将降低LED的成本，在普通照明市场广泛采用白光LED，并显著节约能源。该项目由材料研究部和促进竞争研究的既定计划（EPSCoR）共同资助。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。

Lighting accounts for one-eighth of total U.S. electricity consumption. Conventional light sources such as incandescent light bulbs and fluorescence light tubes consume a lot of energy. Light-emitting diodes (LEDs) as a new generation lighting technology have extremely long life spans and consume much less energy. Despite rapid advances, LED technology is still in its early stage, and continued innovation and breakthroughs are needed to achieve the full potential of this technology. White LEDs are typically obtained by coating yellow luminescence materials (called “phosphor”) onto blue LEDs. The lack of red component results in a cool color, which is not suitable for indoor lighting applications. The objective of this CAREER project is to develop highly efficient, environmentally friendly luminescent materials by using earth-abundant elements and low-cost and large-scale solution-based methods to replace the yellow phosphors. The project aims to develop highly efficient white LEDs with superior color quality, to speed up the widespread adoption of white LEDs, and to save energy. This project offers educational training in multidisciplinary areas such as Physics, Material Science, Electrical Engineering, and Mechanical Engineering for both undergraduate and graduate students. The research is also integrated with photonic education activities at local K-12 schools. This project is jointly funded by the Division of Materials Research and the Established Program to Stimulate Competitive Research (EPSCoR).Metal halide perovskites are promising semiconductor materials for potential applications in optoelectronic devices. However, the common inclusion of lead and stability issues of this material are hampering the practical applications of these materials. The Principal Investigator is exploring new lead-free pseudohalide/halide perovskite nanocrystals and investigating the factors affecting their optical properties and stability by using theoretical and experimental methods. The knowledge obtained in this project improves our fundamental understanding of the physics of pseudohalide/halide perovskite materials and assists in discovering new environmentally friendly materials for next-generation white LEDs. The project expects to solve the issues challenging the practical applications of these materials and to accelerate their use in optoelectronic devices. The completion of this project results in a cost reduction of LED, widespread adoption of white LED in the general illumination market, and significant energy savings. This project is jointly funded by the Division of Materials Research and the Established Program to Stimulate Competitive Research (EPSCoR).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.