Collaborative Research: SusChEM: Mechanistic origins of synergetic effects in plasma catalysis

研究机构：马里兰大学帕克分校/明尼苏达大学双子城分校。拟建的合作研究项目旨在利用表征良好的常压等离子体源，实现等离子体与地球上丰富的催化剂的良好控制相互作用。等离子体催化剂的活化对于提高催化系统的效率有着巨大的希望，在广泛的行业中有潜在的应用，包括化学和材料合成、环境修复和能源生产。该项目的首要目标是研究等离子体与催化剂协同作用的潜在机制。计划是将等离子体催化协同效应的大小与入射的反应物质通量，以及催化剂表面性质和表面电子结构的变化联系起来。对不同催化剂进行仔细的系统比较可以阐明协同效应的微观起源，并探索热失活催化剂的潜在等离子体活化。该项目可能有助于更好地了解等离子体条件和催化剂的要求，以充分利用等离子体-催化剂系统的协同潜力。提出了一项机制研究，旨在提供原子的见解，以揭示等离子体-催化剂相互作用期间协同效应的关键机制。铁、镍、钴和铜载体催化剂（氧化铝和二氧化硅载体）将在本研究中使用。由于不同的电子结构和表面催化机理，这些催化剂的热催化活性差异很大。本文将重点研究等离子体-表面相互作用条件改变时氧/甲烷模型体系催化剂的原子表面修饰。这将包括这些表面变化对形成的产品及其形成速率的影响。气相表征将通过分子束质谱和双光子激光诱导荧光来实现。表面表征将包括椭偏、紫外和x射线诱导光发射光谱加上热解吸和傅里叶变换红外光谱。所提出的方法有可能对当前最先进的技术进行革命性的改变，使催化剂的机械信息设计非常适合等离子体-催化剂协同作用。除了培训研究生和本科生外，研究人员还计划为中学生开发关于等离子体催化的课程材料和互动讲座。

1703211 / 1703439PI: Oehrlein, Gottlieb S. / Bruggeman, Peter J. Institution: University of Maryland College Park / University of Minnesota-Twin CitiesThe proposed collaborative research project aims at using a well-characterized atmospheric-pressure plasma source to enable well-controlled interactions of the plasma with earth-abundant catalysts. The activations of catalysts using plasmas holds great promise for increasing the efficiency of catalytic systems with potential applications in a broad spectrum industries, including chemical and materials synthesis, environmental remediation, and energy generation. The overriding goal of the proposed project is to investigate the underlying mechanisms that are responsible for the synergistic effects of plasma with catalysts. The plan is to correlate the magnitude of the plasma catalytic synergistic effect(s) with incident reactive species fluxes, along with changes in catalyst surface properties, and surface electronic structure. A careful systematic comparison of the different catalysts may elucidate the microscopic origins of the synergistic effect and explore potential plasma activation of thermally inactive catalysts. The project may lead to better understanding of the requirements for plasma conditions and catalysts to fully exploit the synergistic potential of plasma-catalyst systems.A mechanistic study is proposed that is aimed at providing atomistic insights to unravel the key mechanisms responsible for the synergistic effect(s) during plasma-catalyst interactions. Iron, nickel, cobalt, and copper supported catalysts (on alumina and silica supports) will be employed in this study. These catalysts vary strongly in thermal catalytic activities due to different electronic structure and surface-catalytic mechanisms. The investigation will be focused on studying atomistic surface modifications of the catalysts for the oxygen/methane model system as the plasma-surface interaction conditions are changed. This will include the impact of these surface changes on the products formed and their formation rates. Gas phase characterization will be achieved by molecular beam mass spectrometry and two-photon laser induced fluorescence. Surface characterization will include ellipsometry, ultra-violet and x-ray induced photoemission spectroscopy coupled with thermal desorption, and Fourier transform infrared spectroscopy. The proposed approach has the potential to make transformative changes to the current state-of-the-art by enabling a mechanistically informed design of catalysts ideally suited for plasma-catalyst synergies. In addition to training graduate and undergraduate students, the investigators plan to develop course material on plasma-catalysis and an interactive lecture for middle school students.