CAS: Molecular Design of Photoactive Covalent Organic Frameworks Capable of Reductive and Oxidative Degradation of Perfluoroalkyl Substances

在化学系化学催化项目的支持下，莱斯大学的Thomas Senftle教授和Rafael Verduzco教授正在研究开发新的光催化材料，用于处理被聚氟烷基和全氟烷基物质（PFAS）污染的水。PFAS分子被统称为“永远的化学物质”，因为它们在环境中不会自然分解，可以积聚在水、土壤和食物来源中。鉴于这些永久性化学品对健康构成的威胁，迫切需要新的方法来清除我们水道中的PFAS污染。为了解决这个问题，研究团队将开发具有光催化活性的纳米结构、高多孔材料，使PFAS能够同时吸附和降解，将其转化为良性产物。具体来说，该团队正在开发光化学活性共价有机框架（COFs），用于去除水中的PFAS。COFs是完全有机的大分子，具有蜂窝状的分子结构，莱斯大学的科学家们将寻求设计这些材料，使其与PFAS发生强烈的相互作用，以进行吸附和光化学降解。该项目有潜力推动低成本方法的发展，以修复pfas污染的水，最终发展可持续和经济上可行的水处理方法。该项目还将设立新的外联活动。pi将接待来自当地社区大学的学生，为学生提供动手实验经验，否则他们的研究机会将有限。这些pi还将通过莱斯大学的教师研究经验（RET）项目与当地一所高中的教师合作，该项目将生产高质量的学习模块，以支持休斯顿地区的K-12 STEM教育。在这个项目中，dr。Senftle和Verduzco及其团队将应用计算和实验方法开发共价有机框架（COFs）作为降解多氟烷基和全氟烷基物质（PFAS）的光催化剂。COFs的模块化特性为调整其与PFAS分子的相互作用提供了多种途径，可用于增强吸附和控制催化降解机制。该小组将研究一系列具有主链和侧链功能化变化的COF结构，这有望提高对控制光催化PFAS降解机制的结构-性能关系的认识。模拟和实验相结合的使用有望使人们更好地了解影响COF作为吸附剂和光催化剂性能的物理机制。研究将集中在澄清光电性质在电子尺度上的影响，以更好地理解分子在原子尺度上的扩散和吸附。该项目旨在提供新的设计原则，以增强PFAS在光催化COF材料中的吸附和降解。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。

With the support of the Chemical Catalysis program in the Division of Chemistry, Professors Thomas Senftle and Rafael Verduzco of Rice University are studying the development of new photocatalytic materials for treating waters contaminated with poly- and perfluoroalkyl substances (PFAS). PFAS molecules are collectively known as “forever chemicals” because they do not break down naturally in the environment and can accumulate in water, soil, and sources of food. Given the health risks posed by such forever chemicals, new methods are urgently needed for removing PFAS contamination from our waterways. To address this problem, the research team will develop nanostructured, highly porous materials that are also photocatalytically active, enabling the simultaneous adsorption and degradation of PFAS to convert them to benign products. Specifically, the team is developing photochemically-active covalent organic frameworks (COFs) for removal of PFAS from water. COFs are fully organic macromolecules with a honeycomb-like molecular structure, and the Rice scientists will seek to engineer these materials to interact strongly with PFAS for both adsorption and photochemical degradation. This project has the potential to advance the development of low-cost approaches for remediating PFAS-contaminated water, toward ultimately developing sustainable and economically viable approaches for water treatment. The project also will establish new outreach activities. The PIs will host students from a local community college to provide hands-on laboratory experience for students who otherwise would have limited research opportunities. The PIs also will work with teachers from a local high school through a Research Experiences for Teachers (RET) program at Rice University, which will produce high-quality learning modules to bolster K-12 STEM education in the Houston area.Under this project, Drs. Senftle and Verduzco and their team will apply computational and experimental methods to develop covalent organic frameworks (COFs) as photocatalysts for the degradation of poly- and perfluoroalkyl substances (PFAS). The modular nature of COFs offers several avenues for tuning their interactions with PFAS molecules, which can be used to enhance adsorption and control catalytic degradation mechanisms. The group will study a series of COF structures with variations in backbone and side-chain functionalization, which is expected to enhance to provide knowledge of the structure-property relationships that govern photocatalytic PFAS degradation mechanisms in COFs. The combined use of simulation and experiment is expected to lead to an improved understanding of the physical mechanisms that influence COF performance both as an adsorbent and a photocatalyst. Studies will focus on clarifying the influence of optoelectronic properties at the electronic scale to better understanding molecular diffusion and adsorption at the atomic scale. The project aims to deliver new design principles for enhancing PFAS adsorption and degradation in photocatalytic COF materials.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.