CAREER: Accelerating sustainable water treatment using smart ultraviolet light emitting diodes

在过去的几十年里，发光二极管，简称LED，已经成为几乎每个家庭的常见特征。最近，研究人员发明了可以发出高能紫外线(UV)的LED。紫外线已被广泛应用于各个领域，包括水处理行业，用于杀灭细菌和去除水中的污染物。然而，相对较高的成本和较低的能源效率阻碍了UV技术在水务行业的采用。与现有的紫外光技术相比，紫外光LED具有更高的能效、更高的耐用性、更低的成本和数字接口能力，因此具有许多优势。这个职业项目的目标是开发第一个使用新型快速脉冲紫外光LED的智能紫外光LED系统。这将通过一系列实验来实现，以了解紫外线催化的化学反应杀灭病原体和降解污染物的机制。这项研究的成功完成将通过开发手持设备，在偏远地区以更低的成本更有效地处理水，从而在全球范围内带来好处。这项研究将与一个教育项目相结合，该项目的重点是让初中生参与STEM活动，以提高科学素养。大学生将有机会出国留学，前往发展中国家测试新设备，同时培训研究生进行尖端科学实验。该项目的总体目标是从机理上理解UV-LED催化的光化学反应，以便能够设计智能UV-LED技术。具体地说，研究目标是：1)识别和选择氯光分解过程中产生的特定自由基，以优化复杂水基质中的微污染物降解；2)利用对UV-LED灯应用占空比的能力，以增强UV和化学-UV消毒过程，以扰乱细胞修复并实现对细胞组件的定向破坏；以及3)让高中实习生、本科生和研究生参与设计和测试适用于发展中国家的新型UV-LED设备。该项目将使用定制设计的LED光反应器、一套基于电子自旋共振光谱的最先进的自由基表征技术，以及阐明细胞破坏的潜在机制的微生物分析来完成。便携式智能UV-LED设备将使用Arduino微控制器来控制脉冲频率和占空比。总而言之，这些改进将为可持续水处理、水再利用和使用点技术的下一次飞跃铺平道路。这项研究的成功完成将有可能促进相关领域的基础科学进步，如聚合物固化和光刻。这项研究将与STEM教育和推广工作紧密结合，以培训和鼓励下一代水科学和技术领域的领导者。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Over the past few decades, light emitting diodes, or LEDs for short, have become a common feature in nearly every home. More recently, researchers have created LEDs that can shine high-energy ultraviolet (UV) rays. UV rays have been widely used in various fields, including in the water treatment industry to kill germs and to remove pollutants in water. However, the adoption of UV technology in the water industry has been hindered by relatively higher cost and low energy efficiency. UV LEDs have many advantages over existing UV light technology due to greater energy efficiency, greater durability, lower cost, and ability for digital interfacing. The goal of this CAREER project is to develop the first Smart UV LED systems utilizing novel rapid pulsed UV LEDs. This will be achieved through a series of experiments to understand the mechanisms for UV catalyzed chemical reactions to kill pathogens and degrade pollutants. Successful completion of this research will provide benefits globally through the development of hand-held devices for more efficient treatment of water at lower cost in remote places. This research will be integrated with an education program focused on engaging middle and high school students in STEM activities to increase scientific literacy. College students will have opportunities for study abroad trips to developing countries to test new devices while training graduate students to perform cutting edge scientific experiments. The overall goal of this project is to develop a mechanistic understanding of UV-LED catalyzed photochemical reactions to enable the design of Smart UV-LED technologies. Specifically, the research objectives are to: 1) identify and select for specific radicals produced during chlorine photolysis to optimize micropollutant degradation in complex water matrices; 2) harness the ability to apply a duty cycle to UV-LED lamps to enhance UV and chemical-UV disinfection processes to disrupt cellular repair and achieve targeted damage of cellular components; and 3) to include high school research interns, undergraduates, and graduate students in the process of designing and testing novel UV-LED devices for application in developing countries. The project will be accomplished using custom-designed LED photoreactors, a suite of state-of-the-science radical characterization techniques based on electron spin resonance spectroscopy, and microbiological assays to elucidate the underlying mechanisms of cellular disruption. Portable, Smart UV-LED devices will be constructed using Arduino microcontrollers to control the pulse frequency and duty cycle. Together, these improvements will pave the way for the next leap forward in sustainable water treatment, water reuse, and point-of-use technologies. Successful completion of this research will have potential to contribute to fundamental scientific advancement in related fields such as polymer curing and photolithography. The research will be tightly integrated with STEM education and outreach efforts to train and encourage the next generation of leaders in water science and technology.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.