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

NSF 13-1179纳米技术的环境健康与安全项目经理：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：碳基纳米级材料，如富勒烯和纳米管，特别是已经提出了各种应用，现在正在轨道上被广泛生产在工业规模上。大气过程（如氧化反应场景）在显著改变富勒烯环境行为方面的作用，包括：溶解度、（生物）可利用性、反应性、稳定性、毒性和总体环境影响，这是目前极度缺乏信息/数据的特别感兴趣的问题。该项目旨在从根本上评估各种高度控制的大气条件下固态和水性富勒烯的反应性（包括动力学和衍生物分析），重点是氧化途径。这个项目的首要假设是C60，作为一种典型的富勒烯，可以被化学氧化和物理改变，通过各种氧化过程，但在大气中无处不在。子假设包括：(A)多个相互竞争的氧化反应同时发生，尽管具有不同的动力学，产生相应的各种衍生物；(B)在“湿”条件下（10% RH），富勒烯将变得越来越亲水，溶解聚集体，在初始氧化后以水解为主要反应；(C)模型（大气）有机物和无机物在气相中会改变这些动力学；(D)“湿”反应（10% RH）的反应产物在水体系中相对稳定；而在“干燥”反应条件下，衍生物在含水暴露时将继续与水反应。智力优势：在这个项目结束时，我们将大大提高对环境相关化学机制/途径和物理化学因素的理解，这些因素控制富勒烯在大气条件下聚集、转化和稳定性的速度和程度。这些信息除了有助于富勒烯毒理学研究的解释外，还将提供对物质生命周期的基本理解。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，并将有助于绿色富勒烯化学的发展。更广泛的影响：除了创造和传播有关工业生产的工程纳米材料决策所需的新技术知识之外；该项目（平台）旨在广泛影响本科和研究生的教育和研究，除了有助于具体的K-12外展计划。研究生和本科（项目集成）教育以及高度跨学科的研究将加强我们在一个新兴需求领域的人力资源基础，在这个领域合格的研究人员供不应求，但是可持续纳米技术的发展需要这些研究人员。此外，PI将支持和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）：激励学院提供专业知识和定期指导，为学生准备当地，区域和国际科学博览会项目和竞赛。

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.