SusChEM: Collaborative Research: Atomic Level Properties of Nanoscale Metal Phosphide Catalysts for Heteroatom Removal Reactions

在这个由化学系化学催化项目资助的项目中，西华盛顿大学的Mark Bussell教授和Takele Seda教授、韦恩州立大学的Stephanie Brock教授和弗吉尼亚理工大学的S. Ted Oyama教授正在研究一种新型材料的基本特性，这种材料可以去除石油和其他油类中的杂质。这种由与磷结合的金属组成的新材料被称为金属磷化物，已被证明能够从石油和其他由植物或食物来源制成的油中去除硫、氮和氧杂质。对这种去除催化剂的需求很高，因为所有这些油都含有大量杂质，并且必须以符合严格环境标准的方式去除它们。通过合作，该项目的研究人员正在探索金属磷化物的颗粒大小、形状和组成对其基本催化性能的作用，为这些有前途的催化剂的改进和商业化提供新的信息。基于金属磷化物的新一代催化剂的开发将对美国和全球产生积极的经济和环境影响。合作团队由PI Bussell和共同PI Seda组成，他们是一所主要的本科院校的教员，共同PI Brock是一所城市研究型大学的教员，共同PI Oyama在美国和日本的大型研究型大学担任联合职务，他们包含了各种各样的参与者。参与该项目的教师和学生正在参加K-12外展活动，以教育和招募下一代STEM人才，以解决世界面临的一系列能源问题。过渡金属磷化物具有成为高活性加氢脱硫（HDS）和加氢脱氧（HDO）催化剂的潜力。虽然金属磷化物代表了加氢处理应用的有前途的下一代催化剂，但在活性位点密度、表面组成和抗中毒/失活机制的影响已知之前，这种磷化物催化剂的改进和商业化前景面临重大挑战。本项目的目的是确定颗粒大小、颗粒形状和组成在决定包裹在介孔氧化物壳中的金属磷化物纳米颗粒的活性和选择性方面的作用，以用于HDS和HDO反应。预成型颗粒之所以被研究，是因为它们可以制备成几乎单分散的样品，尺寸范围在2-30纳米之间，也可以制备成球形或棒状单晶，从而可以量化活性位点密度（以及周转率（tof）），并评估不同晶面的相对活性。合作团队的每个成员都具有独特的表征能力，可以研究定义良好的金属磷化物纳米颗粒催化剂的结构细节。本文提出的核壳纳米催化剂的研究活动将使我们能够探索金属磷化物上HDS和HDO的基本化学性质，为这些有前景的催化剂的改进和商业化提供新的信息。

In this project funded by the Chemical Catalysis program of the Chemistry Division, Professors Mark Bussell and Takele Seda of Western Washington University, Professor Stephanie Brock of Wayne State University and Professor S. Ted Oyama of Virginia Tech are investigating the fundamental properties of a new class of materials for the removal of impurities from petroleum and other oils. The new materials, composed of metals bonded to phosphorus, are known as metal phosphides and have been shown capable of removing sulfur, nitrogen and oxygen impurities from both petroleum and other oils made from plant or food sources. The need for such removal catalysts is high because all these oils contain substantial impurities, and removing them must be done in such a way that stringent environmental standards are met. By working collaboratively, the researchers on this project are probing the role of particle size, shape and composition on the fundamental catalytic properties of metal phosphides, providing new information for the improvement and commercialization of these promising catalysts. The development of a new generation of catalysts based on metal phosphides would have positive economic and environmental impacts in the U.S. and globally. The collaborative team consisting of PI Bussell and co-PI Seda, faculty members at a predominantly undergraduate institution, co-PI Brock, a faculty member at an urban research university, and co-PI Oyama, who has joint appointments at large U.S. and Japanese research universities, embraces a diverse range of participants. The faculty and students involved in this project are participating in K-12 outreach to educate and recruit the next generation of STEM talent to address the range of energy issues facing the world. Transition metal phosphides have the potential to be highly active hydrodesulfurization (HDS) and hydrodeoxygenation (HDO) catalysts. While metal phosphides represent a promising next generation catalyst for hydrotreating applications, until the effects of active site density, surface composition, and mechanism of resistance to poisoning/deactivation are known, the prospects for improvement and commercialization of such phosphide catalysts face significant challenges. The aims of this project are to determine the roles of particle size, particle shape and composition in determining the activity and selectivity of metal phosphide nanoparticles encapsulated in mesoporous oxide shells for the HDS and HDO reactions. Pre-formed particles are being investigated because they can be prepared as nearly monodisperse samples in sizes ranging from 2-30 nm, and as spherical or rod-shaped single crystallites, thereby enabling quantification of the active site density (and thus turnover frequencies (TOFs)) as well as assessment of the relative activity of different crystal faces. Each member of the collaborative team brings unique characterization capabilities for investigating the structural details of the well-defined metal phosphide nanoparticle catalysts. The proposed research activities with core-shell nanocatalysts will allow us to probe the fundamental chemistry of HDS and HDO over metal phosphides, providing new information for the improvement and commercialization of these promising catalysts.