Collaborative Research: Heterogeneous Photocatalytic Transformation of Isoprene: Relevance to Secondary Organic Aerosol Formation

合作研究：异戊二烯的多相光催化转化：与二次有机气溶胶形成的相关性

• 批准号: 0964853
• 负责人: Michael Hoffmann
• 金额: $ 47.19万
• 依托单位: California Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-01 至 2013-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0964853&HistoricalAwards=false
• 关键词: Collaborative; Research; Heterogeneous; Photocatalytic; Transformation

The hypothesis to be tested in this project is that atmospheric heterogeneous photocatalysis of isoprene may play an important role in secondary organic aerosol (SOA) formation. The atmospheric relevance of transition metal-based particulate semiconductors in the photochemical oxidation of isoprene to low volatility products will be investigated. Photocatalysts will include atmospherically-relevant transition metal oxide particles, desert sand, and volcanic ash in the 0.1 to 10 micrometer size range. Liquid-solid photocatalytic reactions will be studied in terms of the organic substrate (isoprene and the primary products of isoprene gas-phase photochemical oxidation, methacrolein and methyl vinyl ketone), the presence of a sacrificial electron donor (e.g., acetate), oxygen concentration, and pH. The potential for photochemical Diels-Alder reactions to occur between isoprene (a diene) and a range of relevant dienophiles will be investigated, followed by analysis for oligomeric products. The research will be overseen by senior investigators from CalTech and the Oak Crest Institute of Science.These studies will potentially advance the field of aerosol research by guiding future smog chamber studies; identifying chemical markers characteristic of heterogeneous photooxidation pathways; and investigating the polymerization products, which may account for a significant portion of the SOA mass. The research will be carried out by a post-doctoral scholar, and a graduate student at Caltech, as well as community college students and high school teachers working in teams with high school students via Oak Crest. These efforts will help to broaden the participation of underrepresented groups in scientific research.

本项目要验证的假设是，异戊二烯的大气多相光催化可能在二次有机气溶胶（SOA）的形成中起重要作用。过渡金属基颗粒半导体在异戊二烯光化学氧化生成低挥发性产物中的大气相关性将被研究。光催化剂将包括与大气相关的过渡金属氧化物颗粒、沙漠沙子和0.1至10微米尺寸范围内的火山灰。将根据有机底物（异戊二烯和异戊二烯气相光化学氧化的主要产物，甲基丙烯醛和甲基乙烯酮），牺牲电子供体（例如，醋酸酯）的存在，氧浓度和ph值研究液固光催化反应。将研究异戊二烯（二烯）和一系列相关的亲二烯试剂之间发生光化学diols - alder反应的可能性，然后分析低聚物产物。这项研究将由加州理工学院和橡树峰科学研究所的高级研究人员监督。这些研究将通过指导未来的烟雾室研究，潜在地推动气溶胶研究领域的发展；鉴定非均质光氧化途径的化学标记研究聚合产物，这可能占SOA质量的很大一部分。这项研究将由一名博士后学者和加州理工学院的一名研究生，以及社区大学生和高中教师通过Oak Crest与高中生组成团队进行。这些努力将有助于扩大代表性不足的群体对科学研究的参与。