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，莱斯大学的托马斯·森夫特尔教授和拉斐尔·弗杜斯科教授正在研究开发新的光催化材料，用于处理被聚和全氟烷基物质（PFAS）污染的沃茨。PFAS分子被统称为“永久化学品”，因为它们不会在环境中自然分解，并且可以在水，土壤和食物来源中积累。考虑到这些永久性化学品带来的健康风险，迫切需要新的方法来消除我们水道中的PFAS污染。为了解决这个问题，研究小组将开发纳米结构的，高度多孔的材料，这些材料也具有光催化活性，能够同时吸附和降解PFAS，将其转化为良性产品。具体来说，该团队正在开发光化学活性共价有机框架（COFs），用于从水中去除PFAS。COF是具有蜂窝状分子结构的完全有机大分子，Rice科学家将寻求设计这些材料，使其与PFAS强烈相互作用，以实现吸附和光化学降解。该项目有可能促进开发低成本的方法来修复PFAS污染的水，最终开发可持续和经济可行的水处理方法。该项目还将开展新的外联活动。PI将接待来自当地社区学院的学生，为那些研究机会有限的学生提供实践实验室经验。PI还将通过莱斯大学的教师研究经验（RET）计划与当地高中的教师合作，该计划将制作高质量的学习模块，以支持休斯顿地区的K-12 STEM教育。Senftle和Verduzco博士及其团队将应用计算和实验方法开发共价有机框架（COFs）作为光催化剂，用于降解聚乙烯。全氟烷基物质（PFAS）。COF的模块化性质为调节其与PFAS分子的相互作用提供了几种途径，这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骨架和侧链官能化变化的COF结构，预计这将增强对COF中光催化PFAS降解机制的结构与性质关系的了解。模拟和实验相结合的使用，预计将导致更好地理解的物理机制，影响COF性能作为吸附剂和光催化剂。研究将侧重于澄清在电子尺度上的光电性能的影响，以更好地理解在原子尺度上的分子扩散和吸附。该项目旨在提供新的设计原则，以提高光催化COF材料中PFAS的吸附和降解。该奖项反映了NSF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.