NSF-DFG Echem: CAS: Spin-polarized electron currents for spin-selective electrocatalysis

在NSF化学部的资助下，这项研究计划涉及匹兹堡大学的大卫沃尔德克教授和明斯特大学（德国）的合作者，他们将探索使用自旋极化电子来提高电催化中的化学选择性和能源效率。基于手性诱导的自旋选择性效应的思想，拟议的研究将开发新的电极材料和电极设计，用于产生自旋极化电子，并评估其作为电催化剂的性能。手性催化剂和手性电极可用于产生自旋极化电子流，然后可用于促进特定的化学反应途径的想法代表了电催化和电合成的一种全新方法。由于析氧反应已被广泛研究与非手性电催化剂，是至关重要的能源技术，并涉及生产双原子氧（其中有两个不成对的电子自旋），它将被用作模型系统，以检查自旋极化电子电流的重要性，在电催化。参与这项研究的学生将有机会参与美国和德国机构之间的交流。匹兹堡大学大卫沃尔德克教授与德国明斯特大学（德国）的合作者共同开展的这项研究项目，主要有三个方面的内容。在每种情况下，自旋极化电子电流的程度将与电催化的选择性和/或效率相关。推力1将研究一系列的手性金属氧化物，其非手性类似物是已知的析氧反应的良好催化剂。从简单的手性金属氧化物开始，继续双层和掺杂复合材料的电催化剂的自旋过滤性能和电催化性能将被评估，并与它们的非手性类似物进行对比。推力2将开发复合材料，其中非手性电催化剂嵌入在手性载体基质中，以赋予自旋极化，从而在析氧催化剂上产生三重态氧的选择性。推力3将创建和开发用作电催化剂的手性超材料。使用纳米光刻方法，该团队将制造包含纳米级金属（或金属氧化物）螺旋的电催化膜，这些螺旋将光能耦合到催化剂中，并产生自旋极化电子来驱动电催化。这项研究为如何设计手性无机膜以提高自旋极化电子电流的产生以及如何将其用作一类新的电催化剂提供了新的见解。 虽然主要的努力将应用于析氧反应，我们从自旋极化电子流的产生过程中获得的见解，有望直接应用于其他电合成反应的电催化剂的设计。这项研究是由美国国家科学基金会-DFG电合成和电催化牵头机构活动资助的（NSF-DFG ECHEM）机会NSF 20- 578.该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

With funding from the NSF Division of Chemistry, this research program involving Professor David Waldeck of the University of Pittsburgh and collaborators at the University of Münster (Germany) will explore the use of spin-polarized electrons to improve the chemical selectivity, and energy efficiency, in electrocatalysis. By building on ideas from the chiral induced spin selectivity effect, the proposed research will develop new electrode materials and electrode designs for generating spin polarized electrons and evaluate their performance as electrocatalysts. The idea that chiral catalysts and chiral electrodes can be used to generate spin-polarized electron currents which can then be used to promote particular chemical reaction pathways represents a fundamentally new approach for electrocatalysis and electrosynthesis. Because the oxygen evolution reaction has been widely studied with achiral electrocatalysts, is critically important for energy technologies, and involves the production of diatomic oxygen (which has two unpaired electron spins), it will be used as a model system to examine the importance of spin polarized electron currents in electrocatalysis. Students involved in this research will have the opportunity to engage in exchange between the US and German institutions. The team will conduct outreach activities involving K-12 students in the Pittsburgh area that promote interest in STEM fields.This collaborative research project of Professor David Waldeck of the University of Pittsburgh and collaborators at the University of Münster (Germany) has three major thrusts. In each case, the extent of spin-polarized electron currents will be correlated with the selectivity and/or efficiency of electrocatalysis. Thrust 1 will investigate a range of chiral metal oxides, whose achiral analogues are known to be good catalysts for the oxygen evolution reaction. Starting with simple chiral metal oxides and continuing with bilayer and doped composites the electrocatalysts spin-filtering properties and electrocatalytic performance will be evaluated and contrasted with their achiral analogues. Thrust 2 will develop composite materials in which achiral electrocatalysts are imbedded in a chiral support matrix to impart spin polarization and hence selectivity for triplet oxygen production on oxygen evolution catalysts. Thrust 3 will create and develop chiral metamaterials for use as electrocatalysts. Using nanolithography methods, the team will fabricate electrocatalytic films comprising nanoscale metal (or metal oxide) helices that couple light energy into the catalyst and generate spin polarized electrons to drive the electrocatalysis. The research promises new insights into how chiral inorganic films can be designed to improve the generation of spin-polarized electron currents and how they can be employed as a new class of electrocatalysts. Although the major effort will be applied to the oxygen evolution reaction, the insights gained for the production of spin-polarized electron currents are expected to be directly applicable to the design of electrocatalysts for other electrosynthesis reactions.This research was funded under the NSF-DFG Lead Agency Activity in Electrosynthesis and Electrocatalysis (NSF-DFG EChem) opportunity NSF 20-578.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.