Collaborative Research: Highly Selective Photocatalysis on TiO2 with Atomically Dispersed Active Centers

合作研究：具有原子分散活性中心的二氧化钛的高选择性光催化

• 批准号: 1924545
• 负责人: De-en Jiang
• 金额: $ 15万
• 依托单位: University of California-Riverside
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2022-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1924545&HistoricalAwards=false
• 关键词: Collaborative; Research; Highly; Selective; Photocatalysis

Catalysts accelerate chemical reactions toward preferred products with significant savings in energy and capital costs. Photocatalysts - those that rely on the sun's energy - offer a path to sustainable manufacturing of fuels and chemicals, and also facilitate remediation of environmental pollutants. The project will investigate novel photocatalyst designs for upgrading natural gas to higher-value products and clean-up of nitric oxide from air pollutants. The research will be supplemented by a broad range of educational and outreach activities aimed primarily at K-12 and undergraduate students from underrepresented backgrounds.The project enlists the expertise of three investigators with skills in catalyst synthesis, spectroscopic characterization techniques, and computational catalysis to prepare and characterize structurally well-defined and atomically-dispersed active sites on heterogeneous catalysts. The catalysts will be evaluated for their ability to control the product selectivity of photo-driven reactions and to elucidate the corresponding reaction mechanisms. This project responds to a critical challenge in heterogeneous catalysis that traditional synthesis methods often lead to a variety of catalytic sites that are structurally poorly defined. This diversity of active sites leads to poor reaction selectivity and hinders elucidation of reaction mechanisms. The researchers will address these challenges by synthesizing atomically-dispersed active centers, mononuclear metal sites and surface oxygen vacancies, on titanium dioxide, a prototypical photocatalyst. The project focuses on two technologically important reactions, the oxidation of methane to methanol and the reduction of NO to dinitrogen. The effort involves characterization of the catalysts with advanced techniques, such as HAADF-STEM and EXAFS. Operando infrared, Raman, and X-ray spectroscopies will be employed to provide insights into the mechanism of the surface reactions. DFT calculations will further complement the mechanistic information. The project is expected to generate novel insights into the factors that govern the reaction selectivity of heterogeneous catalytic reactions. The team will pursue a multi-pronged approach to engage underrepresented minorities in this research at their respective institutions and to educate the general public about photocatalysis. Specific activities include participation in the NSF-sponsored Research Experience for Undergraduates (REU) Program, an innovative course for freshmen undergraduate students whose primary declarations are not in the sciences, engagement in outreach activities with local high schools, and a collaborative effort with high-school teachers to introduce students to molecular modeling.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

催化剂加速了化学反应，以节省能源和资本成本的优选产品。 光催化剂 - 依靠太阳能量的光催化剂为燃料和化学物质的可持续制造提供了一条途径，并促进了对环境污染物的修复。 该项目将研究用于将天然气升级到高价值产品的新型光催化剂设计，并从空气污染物中清理一氧化氮。 这项研究将以各种各样的背景不足的K-12和本科生的广泛教育和外展活动进行补充。该项目吸引了三位具有催化剂合成技能，光谱表征技术和计算催化和表征结构良好和表征性良好型和表征的研究者的研究人员的专业知识。 将评估催化剂的能力，可以控制光驱动反应的产品选择性并阐明相应的反应机理。 该项目应对异质催化中的一个关键挑战，传统的合成方法通常会导致各种结构上定义较差的催化位点。这种活跃位点的多样性导致反应选择性不佳，并阻碍了反应机制的阐明。 研究人员将通过在二氧化钛（一种原型的光催化剂）上合成原子分散的活性中心，单核金属位点和表面氧空位来解决这些挑战。 该项目着重于两个技术上重要的反应，即甲烷对甲醇的氧化以及对二氮的减少。 努力涉及用高级技术（例如HAADF-STEM和EXAFS）对催化剂进行表征。 Operando红外，拉曼和X射线光谱将采用对表面反应机理的见解。 DFT计算将进一步补充机械信息。 预计该项目将对控制异质催化反应的反应选择性的因素产生新的见解。 该团队将采用多管齐下的方法，以在本研究中与代表性不足的少数群体在其各自的机构中参与其中，并向公众教育有关光催化的信息。 具体活动包括参加NSF赞助的本科生（REU）计划的研究经验，这是一项针对新生的创新课程，他们的主要宣言不在科学中，与当地高中进行外展活动，以及与高中的合作努力通过高中培训来介绍分子模型。基金会的智力优点和更广泛的影响评论标准。