US-EGYPT Cooperative Research: Polycyclic Aromatic Hydrocarbon Degradation by Nanostructured TiO2 Thin Films

美国-埃及合作研究：纳米结构TiO2薄膜降解多环芳烃

• 批准号: 0809174
• 负责人: S. Ismat Shah
• 金额: $ 2.99万
• 依托单位: University of Delaware
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-08-01 至 2011-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0809174&HistoricalAwards=false
• 关键词: US; EGYPT; Cooperative; Research; Polycyclic

0809174ShahDescription: This project supports collaborative research by Dr. S. Ismat Shah, Department of Materials Science and Engineering, University of Delaware-Newark. The Egyptian collaborator is Dr. Ahmed Aboul Gheit of the Egyptian Petroleum Research Institute, Cairo, Egypt. They plan to study Polycyclic Aromatic Hydrocarbons (PAHs) degradation. The project includes a systematic study of the synthesis process, characterization of the modified materials, and the degradation mechanism. PAHs are a group of more than 100 chemicals that are emitted when fossil fuels are used under conditions that lead to incomplete burning. Some PAHs are manufactured. They are colorless, white, or pale yellow-green solids. PAHs affect body immune system (effect confirmed only in animals) and are know carcinogens. In addition to their presence in air, they also make their way into the water systems either indirectly from the atmosphere or directly through the industrial waste. This proposal describes a methodology through which a tried and tested material, titanium dioxide (titania), will be used in a unique form (nanostructured thin film) which will allow the known properties of titanium dioxide to be exploited more efficiently for the degradation of PAHs in water. Bulk titania works only with the ultra-violet (UV) light. If natural degradation is desired, titania has to be modified so that the larger portion of the sunlight, the visible light, could be made useful. The heart of the project is to modify titania such that a structure could be formed that is sensitive to visible light. Intellectual Merit: This proposal describes a detailed study of photodegradation of Polycyclic Aromatic Hydrocarbons (PAHs) in water in the presence of a photocatalyst composed of semiconductor metal oxides. PAHs are carcinogens and are present in air and in water. They emanate primarily from incomplete combustion of fossil fuels. The photocatalyst (TiO2) will be in the form of thin films that are fabricated such that there is strong adhesion with the substrates, e.g., glass, etc. The thin film processes to be used include sol-gel, metalorganic chemical vapor deposition (MOCVD), and pulsed laser deposition (PLD). The photodegradation intermediates will be traced using high performance liquid chromatography analysis and degradation reaction path will be studied for samples irradiated at different periods with different irradiation strengths using UV and visible light. Extensive catalysts characterization will be carried out using various techniques including diffraction, microscopy and spectroscopy methods. Furthermore, the composition of the catalyst will be optimized for the phases present (anatase/rutile) or with the addition of dopant, particularly nitrogen, to the principle TiO2 catalyst to enhance its photocatalytic activity. The presence of the nanostructure in the TiO2 thin film form is the unique aspect of this study. Experiments will exploit the additional advantages the nanomaterials provide over bulk material, namely higher surface area, presence of more active metastable phases, and modified band structure better suitable for photocatalysis. Broader Impacts: The project addresses a problem of significant environmental and health impact. The collaboration between Egyptian and US scientists and engineers will be beneficial to both sides. Several U.S. and Egyptian undergraduate and graduate students will be involved in the proposed work. The PI has successfully worked with his Egyptian counterparts, including publishing several joint publications. This project is being supported under the US-Egypt Joint Fund Program.

0809174ShahDescription：该项目支持特拉华大学材料科学与工程系S. Ismat Shah博士的合作研究。 埃及合作者是埃及埃及石油研究所的艾哈迈德·阿布尔·盖伊特（Ahmed Aboul Gheit）博士。他们计划研究多环芳烃（PAHS）降解。 该项目包括对合成过程的系统研究，改良材料的表征以及降解机制。 PAH是一组100多种以上化学物质，当化石燃料在导致不完全燃烧的条件下使用时发出。一些PAH是制造的。它们是无色，白色或浅黄色绿色固体。 PAH会影响人体免疫系统（仅在动物中得到证实），并且已知致癌。除了在空中存在外，他们还间接地从大气或直接通过工业废物进入水系统。该提案描述了一种方法论，该方法将以独特的形式（纳米结构薄膜）使用，经过测试和测试的材料二氧化钛（钛）将允许二氧化钛的已知特性更有效地利用水中的二氧化钛的已知特性。散装二氧化钛仅与超紫罗兰色（UV）光一起使用。如果需要自然降解，则必须修改二氧化钛，以便可以使阳光的较大部分（可见光）变得有用。该项目的核心是修改二氧化钛，以便可以形成对可见光敏感的结构。智力优点：该提案描述了在由半导体金属氧化物组成的光催化剂的存在下，对水中多环芳烃（PAH）的光降解的详细研究。 PAH是致癌物，存在于空气和水中。它们主要来自化石燃料的不完全燃烧。光催化剂（TIO2）将以制造的薄膜形式（TiO2）形式，使得与底物具有较强的粘附力，例如玻璃，玻璃等。要使用的薄膜过程包括Sol-Gel，Metal Grangic Chemical Chemical Chemical Vapor沉积（MOCVD），以及脉冲激光deposite（PLD）。将使用高性能液相色谱分析来追踪光降解中间体，并将研究降解反应路径，以使用紫外线和可见光在不同时期内具有不同照射强度的不同时期的样品。将使用各种技术（包括衍射，显微镜和光谱法）进行广泛的催化剂表征。此外，将针对存在的相（解剖酶/金红石）或将掺杂剂（尤其是氮，尤其是氮）催化剂优化催化剂的组成，以增强其光催化活性。 Tio2薄膜形式中纳米结构的存在是本研究的独特方面。实验将利用纳米材料提供的额外优势，即比散装材料，即更高的表面积，更活跃的亚稳态相位以及改良的带结构更适合于光催化。更广泛的影响：该项目解决了重大环境和健康影响的问题。 埃及和美国科学家和工程师之间的合作将对双方都有利。 美国和埃及本科生和研究生将参与拟议的工作。 PI已成功与他的埃及同行合作，包括出版几家联合出版物。 该项目得到了美国埃及联合基金计划的支持。