Atmospheric Fullerene Chemistry: Elucidating Oxidative Pathways and Characterization of Corresponding Derivatives

NSF 13- 1179纳米技术的环境健康和安全项目经理：Barbara Karn博士提案#1236865大气富勒烯化学：阐明氧化途径和相应衍生物的表征摘要：碳基纳米材料，如富勒烯和纳米管，特别是已被提出用于各种应用，现在正在进行工业规模的广泛生产。特别令人感兴趣的是，目前严重缺乏信息/数据，是大气过程（例如氧化反应情景）的作用，以显着改变广泛的富勒烯环境行为，包括：溶解度，（生物）可用性，反应性，稳定性，毒性和整体环境影响。该项目旨在从根本上评估固态和水溶性富勒烯物种在各种高度受控的大气条件下的反应性（包括动力学和衍生物分析），重点是氧化途径。该项目的首要假设是，C60作为一种模型富勒烯，可以通过大气中各种普遍存在的氧化过程进行化学氧化和物理改变。子假设包括：（A）多个竞争性氧化反应同时发生，尽管具有不同的动力学，产生相应的各种衍生物;（B）在“湿”条件（10%RH）下，富勒烯将变得越来越亲水，溶解聚集体，其中水解是初始氧化后的主要反应;（C）模型气相中的（大气）有机物和无机物将改变这些动力学;（D）来自“湿”反应（10%RH）的反应产物在含水系统中将相对稳定;而在“干燥”反应条件下，衍生物在暴露于水时会继续与水反应。在这个项目结束时，我们将大大提高对环境相关的化学机制/途径和控制富勒烯聚集速率和程度的物理化学因素的理解，在大气条件下的转化和稳定性。这些信息将提供基本的理解材料的生命周期（S）除了在富勒烯毒理学研究的解释帮助。研究结果还将提供有关富勒烯稳定性、储存和商业应用的信息，并将有助于开发绿色富勒烯化学品。该项目（平台）旨在广泛影响本科生和研究生的教育和研究，除了有助于具体的K-12推广计划。研究生和本科（项目综合）教育和高度跨学科的研究将加强我们的人力资源基础，在一个新兴的需求领域，合格的研究人员短缺，但需要可持续的纳米技术的发展。此外，PI将支持并直接与教育工作者和学生合作，在圣路易斯的知识就是力量计划（KIPP）提供专业知识和定期指导：圣路易斯学院，为学生准备当地，区域和国际科学博览会项目和比赛。

NSF 13-1179Environmental Health and Safety of NanotechnologyProgram Manager: Dr. Barbara KarnProposal #1236865Atmospheric Fullerene Chemistry: Elucidating Oxidative Pathways and Characterization of Corresponding DerivativesAbstract: Carbon based nano-scale materials such as fullerenes and nanotubes in particular have been proposed for a variety of applications and are now on track to be widely produced at the industrial scale. Of particular interest, and currently deeply lacking in information/data, is the role of atmospheric processes (e.g. oxidizing reaction scenarios) to significantly alter a wide breadth of fullerene environmental behavior(s) including: solubility, (bio)availability, reactivity, stability, toxicity and overall environmental impact. This project is designed to fundamentally evaluate the reactivity (including kinetic and derivative analyses) of solid state and aqueous available fullerene species under various, highly controlled, atmospheric conditions, focused on oxidation pathways. The overarching hypothesis of this project is that C60, as a model fullerene, can be chemically oxidized and physically altered by a variety of oxidative, yet ubiquitous, processes in the atmosphere. Sub-hypotheses include: (A) Multiple, competing oxidative reactions occur simultaneously, albeit with different kinetics, resulting in corresponding and various derivatives; (B) Under "wet" conditions (10% RH), fullerenes will become increasingly hydrophilic, dissolving aggregates, with hydrolysis as major reaction after initial oxidation; (C) Model (atmospheric) organics and inorganics in the gas phase will modify these kinetics; (D) Reaction products from "wet" reactions (10% RH) will be relatively stable in aqueous systems; whereasunder "dry" reaction conditions, derivatives will continue to react with water upon aqueous exposure.Intellectual Merit: At the conclusion of this project, we will have a vastly improved understanding of environmentally relevant chemical mechanisms/pathways and physico-chemical factors that control the rate and extent of fullerene aggregation, transformation(s) and stabilities under atmospheric conditions. This information will provide fundamental understanding for material life cycle(s) in addition to aiding in the interpretation of fullerene toxicological studies. Results will also provide information regarding fullerene stability, storage and commercial applications, and will contribute to the development of green fullerene chemistries.Broader Impacts: In addition to creating and disseminating new technical knowledge needed for decision-making regarding an industrially produced, engineered nanomaterial; this project (platform) is designed to broadly impact both undergraduate and graduate education and research, in addition to contributing to specific K-12 outreach programs. Graduate and undergraduate(project integrated) education and highly interdisciplinary research will strengthen our human resource base in an emerging need area where qualified researchers are in short supply, yet needed for the development of sustainable nanotechnologies. Furthermore, PI's will support and work directly with educators and students, providing expertise and regular mentoring at the St. Louis' Knowledge is Power Program (KIPP): Inspire Academy, preparing students for local, regional and international science fair projects and competitions.