CAS: Fundamental Experimental-Theoretical Investigations of New Metal Alloy Nanocatalysts for Natural Gas Repurposing

在化学系大分子，超分子和纳米化学项目的支持下，教授们。西蒙·M德克萨斯大学奥斯汀分校的Humphrey和Graeme Henkelman正在领导一项高度合作的研究计划，涉及纳米合金的合成和反应性研究，这些合金能够在甲烷释放的位置将甲烷转化为稳定的液体燃料，如甲醇。 与此同时，天然气燃烧在世界范围内，特别是在美国，是一个日益重要的环境问题。 天然气（即，通过直接燃烧产生二氧化碳来补救在石油回收场所或炼油厂中释放的甲烷）。 虽然甲烷是一种比二氧化碳更强大的温室气体，但燃烧的行为仍然浪费了甲烷，并每年向大气中增加数百万吨额外的二氧化碳。 这是因为压缩甲烷用于运输和最终使用不具有成本效益。 该研究项目是基础性的，旨在了解非贵金属合金的某些成分如何以受控和理想的方式进行目标反应。 该科学项目还通过与创新的本科教育计划相结合而得到显着增强，该计划称为奥斯汀国际框架（AIF），为UT奥斯汀本科生提供完全沉浸式的，奖学金支持的国际交流体验。 它为学生提供了一个独特的机会，以扩大他们的视野，同时赚取课程学分为他们的研究经验。这是一个合作的实验计算研究计划之间的教授组。西蒙·M得克萨斯大学奥斯汀分校的汉弗莱和格雷姆·亨克尔曼。 总体目标是利用专业知识，通过微波辅助加热技术形成新型金属纳米合金，并使用计算机理论指导合成研究，并阐明纳米颗粒催化剂的反应性，作为表面结构和组成的函数。 该项目的具体目标是使用催化价值较低和丰富的钴金属沿着与更高度亲氧的金属如Ru和Re的组合来制备新的二元和三元催化剂，以产生可以模拟更稀有的贵金属的反应性的系统。 除了模拟真实反应条件的模型气相化学反应研究外，还将使用光谱技术（例如，电子显微术、总X射线散射、扩展X射线精细结构、化学吸附等），在原子尺度上提供现实的理论模型。 然后，这种结构信息将被用来建立和完善理论模型，可以确定最重要的活性位点集合。 最终，这使得能够准确预测反应性和选择性，这可以用来为未来的合成目标提供信息，以识别具有所需反应性的最终催化剂：该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的评估被认为值得支持。影响审查标准。

With the support of the Macromolecular, Supramolecular and Nanochemistry Program in the Division of Chemistry, Profs. Simon M. Humphrey and Graeme Henkelman at the University of Texas at Austin are leading a highly collaborative research program involving the synthesis and reactivity studies of nano-sized alloys capable of converting methane into stable liquid fuels such as methanol, at the location where the methane is released. Meanwhile, natural gas flaring is an increasingly significant environmental issue worldwide and particularly in the USA. Natural gas (i.e., methane) that is released at oil recovery sites or in refineries is remediated by direct combustion to give carbon dioxide. While methane is a much more powerful greenhouse gas than carbon dioxide, the act of flaring still wastes the methane and adds millions of tones of extra carbon dioxide into the atmosphere each year. This is because compression of methane for transportation and eventual use is not cost-effective. This research project is fundamental and aims to understand how certain compositions of alloys of non-precious metals can perform the target reactions in a controlled and desirable manner. The scientific project is also significantly enhanced through integration with an innovative undergraduate educational program, called the Austin-International Framework (AIF), which provides a fully immersive, scholarship-supported international exchange experience to UT Austin undergraduates. It provides students the unique opportunity to broaden their horizons, while simultaneously earning course credit for their research experiences.This a collaborative experimental-computational research program between the groups of Profs. Simon M. Humphrey and Graeme Henkelman at the University of Texas at Austin. The overarching aims are to leverage expertise in the formation of novel metallic nanoalloys via microwave-assisted heating techniques, and to use theory in silico to guide synthetic studies and to elucidate the resulting reactivity of the nanoparticle catalysts, as a function of surface structure and composition. The specific goals of this project are to prepare new binary and ternary catalysts using combinations of catalytically less valuable and abundant coinage metals along with more highly oxophilic metals such as Ru and Re, to generate systems that can mimic the reactivity of scarcer noble metals. In addition to model gas-phase chemical reaction studies that mimic realistic reaction conditions, structure-function relationships will be elucidated using a palette of spectroscopic techniques (e.g., electron microscopy, total X-ray scattering, extended X-ray fine structure, chemisorption, etc.), to provide realistic theoretical models at the atomic scale. This structural information will then be used to build and refine theoretical models that can identify then most important active site ensembles. Ultimately this enables accurate predictions of reactivity and selectivity, which can be leveraged to inform future synthetic targets, toward the identification of eventual catalysts with desired reactivity: those that are able to selectively activate CH4 to CH3 and H in the presence of atomic oxygen.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.