CAREER: Rational Design of Efficient Carbon Nanotube-Supported TiO2 Photocatalysts for Air Purification

职业：合理设计用于空气净化的高效碳纳米管负载 TiO2 光催化剂

• 批准号: 1653527
• 负责人: Placidus Amama
• 金额: $ 52万
• 依托单位: Kansas State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-02-01 至 2023-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1653527&HistoricalAwards=false
• 关键词: CAREER; Rational; Design; Efficient; Carbon

PI Name: AmamaProposal Number: 1653527 NO2 is one of six priority air pollutants regulated by the US Environmental Protection Agency and has been linked to health problems (lung diseases, strokes, ischemic heart disease, and cancer), formation of ground-level ozone, and fine-particle pollution. Under ultraviolet (UV) light, titanium dioxide (TiO2) oxidizes low-level NOx (~1 ppm or below) in air to harmless nitrates. This project will provide the framework for the coupling of carbon nanotubes (CNTs) and TiO2 with the goal of enabling low-cost and large-area CNT-based/TiO2 coatings for efficient outdoor pollution control. This technology is expected to provide significant improvement in urban air quality and combat ozone at the source. The educational plan will simultaneously advance scientific discovery and increase the science, technology, engineering, and mathematics (STEM) pipeline, as well as equip engineering students at Kansas State University (KSU) with skillsets for innovative and successful careers in nanotechnology.The objective of this project is to integrate nanotechnology and heterogeneous catalysis to fabricate well-tailored and multifunctional CNT-based composites for environmental remediation. The PI will test the broad hypothesis that photocatalytic activity and photoresponse of CNT-supported TiO2 nanocomposites (CNT/TiO2) are enhanced by the properties of CNTs and resulting interfacial charge transfer properties. The research goal will be achieved by pursuing the following specific tasks: 1) scalable synthesis of highly uniform CNTs [metallic single-walled CNTs (m-SWCNTs), semiconducting SWCNTs (s-SWCNTs), and multiwalled CNTs (MWCNTs)] using an industrial waste gas from Fischer-Tropsch synthesis as a feedstock; 2) controlled CNT functionalization and coupling of CNTs and TiO2 using UV light and a green solvent (H2O2); 3) elucidation of the coupling mechanisms between CNTs and TiO2; and 4) evaluation of the photocatalytic activity of CNT/TiO2 in the oxidation of NOx under various environmental and material variables. This study will illuminate the coupling mechanisms between TiO2 and CNTs and establish structure-property-function relationships. The work is a novel means for maximizing charge-separation efficiency of TiO2 and extending its photoresponse to the visible-light region. The resulting s-SWCNT/TiO2 photocatalyst will provide a transformative pathway for the synthesis of visible-light-active, low-cost, efficient, and large-area CNT-based/TiO2 coatings for the photocatalytic oxidation of NOx. Creation of a scalable and controlled CVD synthesis approach for s-SWCNTs and m-SWCNTs that are orders-of-magnitude higher than conventional post-purification methods will be transformative, as it is a necessary first step for scalable synthesis of well-tailored SWCNT/TiO2 photocatalysts. The use of UV/H2O2 for CNT functionalization during TiO2 deposition will ensure that electrons are freely shuttled along the CNTs; this approach differs from conventional approaches, which largely involve the use of aggressive acid treatment that imparts significant defects on CNTs. The resulting structure-property-function correlations of CNT/TiO2 photocatalysts will substantially improve understanding of the coupling mechanisms and lay a solid foundation for the adoption of the nanocomposites in a number of photocatalytic applications including water splitting, air purification, CO2 reduction, water purification, and microbial inactivation. The international exchange program will benefit both research and education at KSU, as US students will gain valuable global perspective--a critical skill for an engineer in the 21st century.

PI 名称：Amama 提案编号：1653527 NO2 是美国环境保护署监管的六种优先空气污染物之一，与健康问题（肺病、中风、缺血性心脏病和癌症）、地面臭氧的形成、和细颗粒物污染。在紫外线 (UV) 光下，二氧化钛 (TiO2) 可将空气中的低浓度氮氧化物（约 1 ppm 或以下）氧化成无害的硝酸盐。该项目将为碳纳米管（CNT）和TiO2的耦合提供框架，目标是实现低成本、大面积的CNT基/TiO2涂层，以实现有效的室外污染控制。该技术预计将显着改善城市空气质量并从源头对抗臭氧。该教育计划将同时推进科学发现，增加科学、技术、工程和数学 (STEM) 渠道，并为堪萨斯州立大学 (KSU) 的工程学生提供纳米技术创新和成功职业生涯的技能。该项目旨在整合纳米技术和多相催化，制造用于环境修复的定制多功能碳纳米管基复合材料。 PI 将测试一个广泛的假设，即 CNT 支撑的 TiO2 纳米复合材料 (CNT/TiO2) 的光催化活性和光响应因 CNT 的特性和由此产生的界面电荷转移特性而增强。研究目标将通过追求以下具体任务来实现：1）使用费托合成产生的工业废气作为原料； 2) 使用紫外光和绿色溶剂 (H2O2) 控制 CNT 功能化以及 CNT 和 TiO2 的耦合； 3）阐明CNT和TiO2之间的偶联机制； 4）评估不同环境和材料变量下CNT/TiO2在NOx氧化中的光催化活性。本研究将阐明 TiO2 和 CNT 之间的耦合机制，并建立结构-性能-功能关系。这项工作是一种最大化 TiO2 电荷分离效率并将其光响应扩展到可见光区域的新方法。由此产生的s-SWCNT/TiO2光催化剂将为合成可见光活性、低成本、高效、大面积的CNT基/TiO2涂层提供一条变革性途径，用于光催化氧化NOx。为 s-SWCNT 和 m-SWCNT 创建可扩展且受控的 CVD 合成方法，该方法比传统后纯化方法高出几个数量级，这将具有变革性，因为这是可扩展合成精心定制的 SWCNT 的必要的第一步/TiO2光催化剂。在 TiO2 沉积过程中使用 UV/H2O2 进行 CNT 功能化将确保电子沿着 CNT 自由穿梭；这种方法与传统方法不同，传统方法主要涉及使用侵蚀性酸处理，从而在碳纳米管上产生明显的缺陷。由此产生的CNT/TiO2光催化剂的结构-性能-功能相关性将大大提高对耦合机制的理解，并为纳米复合材料在许多光催化应用中的采用奠定坚实的基础，包括水分解、空气净化、二氧化碳还原、水净化和微生物灭活。国际交流计划将有利于堪萨斯州立大学的研究和教育，因为美国学生将获得宝贵的全球视野——这是 21 世纪工程师的关键技能。

项目成果

Efficient Growth of Carbon Nanotube Carpets Enabled by In Situ Generation of Water

• DOI: 10.1021/acs.iecr.0c00711
• 发表时间: 2020-05-13
• 期刊: INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
• 影响因子: 4.2
• 作者: Everhart, Brian M.;Almkhelfe, Haider;Amama, Placidus B.
• 通讯作者: Amama, Placidus B.

Synthesis of ultrathin, nano-sized Ti3C2Tx with abundant =O and –OH terminals and high transparency as a cocatalyst: Enabling design of high-performance Titania-Ti3C2Tx hybrid photocatalysts

• DOI: 10.1016/j.jpcs.2022.110875
• 发表时间: 2022-07
• 期刊: Journal of Physics and Chemistry of Solids
• 影响因子: 4
• 作者: Ahmed Al Mayyahi;Swagotom Sarker;Brian M.Everhart;B. Tonyali;U. Yucel;Placidus B Amama

High-Throughput Experimentation for Selective Growth of Small-Diameter Single-Wall Carbon Nanotubes Using Ru-Promoted Co Catalysts

• DOI: 10.1021/acs.chemmater.2c00347
• 发表时间: 2022-05-24
• 期刊: CHEMISTRY OF MATERIALS
• 影响因子: 8.6
• 作者: Everhart, Brian M.;Rao, Rahul;Amama, Placidus B.
• 通讯作者: Amama, Placidus B.

Photocatalytic NOx Mitigation Under Relevant Conditions Using Carbon Nanotube-Modified Titania

• DOI: 10.1016/j.cej.2022.136984
• 发表时间: 2022-05
• 期刊: Chemical Engineering Journal
• 影响因子: 15.1
• 作者: B. Everhart;Bailey McAuley;Ahmed Al Mayyahi;B. Tonyali;U. Yucel;P. Amama

Hierarchical TiO2-g-C3N4 photocatalyst with purification effect for NOx oxidation under cyan light

• DOI: 10.1016/j.jphotochem.2023.114965
• 发表时间: 2023-10
• 期刊: Journal of Photochemistry and Photobiology A: Chemistry
• 作者: A. A. Mayyahi-A.;Archana Sekar;Sabari Rajendran;Shusil Sigdel;Lian Lu;Juan Wang;Guohong Wang