CAREER: Combining Materials Science and System-Level Analysis to Sustainably Supply Safe Drinking Water

供水基础设施老化是提供安全饮用水的一大挑战，特别是在没有集中式水处理设施的地区。现有的饮用水处理方法需要权衡取舍。例如，用氯处理会产生有害物质，紫外线和臭氧需要很高的能量，而且可能很昂贵。这个职业提案的目标是开发新的材料，可以廉价地利用可见光来产生活性氧物种，作为消毒剂来杀灭水中的病原体。新设计的材料将测试其杀死一系列病原体的能力，包括导致军团菌病的微生物。军团菌病是一种致命疾病，在美国每年造成4亿美元的医疗费用。这项研究的科学发现将用于通过播客提高公众对安全饮用水的认识，公众将在播客中提出问题。在新冠肺炎大流行期间，收听播客的人数显著增加，这表明这将是吸引普通公众的一种有效模式。研究人员还将开发一个讲故事的科学计划，利用饮用水的相关背景来提高K-6学生的知识，以培养对STEM主题的积极态度和认同感。这项职业计划结合了基础科学和环境工程原理，开发了利用节能LED的石墨化碳氮化物(g-C3N4)水处理技术。G-C3N4是一种非金属可见光催化剂，合成成本低，原料丰富，是一种很有前途的饮用水处理替代光催化剂。虽然人们一直在对g-C3N4进行化学修饰以提高光催化性能，但分子结构、物理化学性质和微生物失活之间的联系还没有完全解决。这项工作的总体目标是通过将g-C3N4的性质与材料化学和抗菌效果联系起来，建立一个合理的可见光可持续水消毒设计框架。这样做将使有意的材料设计能够适应一系列水基质和目标细菌。这项研究的一个重要进展包括扩大了饮用水病原体的灭活测试，如嗜肺军团菌、铜绿假单胞菌和非结核分枝杆菌。这将为水处理提供更相关的结果，因为目前90%的研究只集中在大肠杆菌灭活上。最后，本研究将结合生命周期和经济可行性评估，以确保光催化水消毒的可持续发展。PI将与(I)新开发的通过讲故事的科学计划的K-6学生合作，(Ii)通过卡内基科学中心一年一度的科学技术日与6-12名学生合作，以及(Iii)在播客中关注来自我们社区的饮用水问题和关注。通过这些活动，PI旨在展示公众如何成为开发创新的科学和工程解决方案的积极参与者，以应对可持续提供安全饮用水的重大挑战。该奖项反映了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。

Aging water supply infrastructure is a major challenge for providing safe drinking water, particularly in areas not serviced by centralized water treatment facilities. Existing approaches for drinking water treatment have tradeoffs. For example, treatment with chlorine can create harmful substances, and ultraviolet light and ozone require high energy and can be expensive. The goal of this CAREER proposal is to develop new materials that can harness visible light inexpensively to generate reactive oxygen species as disinfectants to kill pathogens in water. The newly designed materials will be tested for the ability to kill a range of pathogens, including the microorganism that causes Legionellosis, a deadly disease responsible for $400 million/year in healthcare costs in the US. The scientific discoveries from this research will be used to improve public awareness of safe drinking water through a podcast in which the public will submit questions. Podcast listening has significantly increased during the COVID-19 pandemic, suggesting this will be an effective mode of engaging the general public. The investigator will also develop a Science Through Storytelling program to enhance K-6 student knowledge using the relatable context of drinking water to develop positive attitudes and sense of identification around STEM topics. This CAREER proposal combines fundamental science and principles of environmental engineering to develop graphitic carbon nitride (g-C3N4) water treatment technologies leveraging energy-efficient LEDs. g-C3N4 is a non-metal, visible-light photocatalyst that is synthesized using low cost, abundant precursors, making it a promising alternative photocatalyst for drinking water treatment. While modifications of g-C3N4 chemistry have been pursued to improve photocatalytic performance, the link between molecular structure, physicochemical properties, and microorganism inactivation is not fully resolved. The overall goal of this work is to establish a rational design framework for visible-light enabled, sustainable water disinfection by connecting g-C3N4 properties to both material chemistry and antimicrobial efficacy. Doing so will enable intentional material design adaptable to a range of water matrices and target bacteria. An important advance of this research includes expanded inactivation testing of drinking water pathogens like Legionella pneumophila, Pseudomonas aeruginosa, and nontuberculous mycobacteria. This will provide more relevant results for water treatment, given that 90% of current studies have focused only on Escherichia coli inactivation. Finally, this research will integrate life cycle and economic feasibility assessment to ensure sustainable advancement of photocatalytic water disinfection. The PI will work with (i) K-6 students in a newly developed Science Through Storytelling program, (ii) 6-12 students through the Carnegie Science Center’s annual SciTech Days, and (iii) the general public in a podcast focused on drinking water questions and concerns sourced from our community. Through these activities, the PI aims to demonstrate how the public can become active participants in developing innovative science and engineering solutions to the grand challenge of sustainably providing safe drinking water.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.