CAREER: SusChEM: Tunable Electrocatalysis at Buried Interfaces

该项目将研究完全或部分被超薄多孔材料层覆盖的金属催化剂的电化学催化作用。将评估涂层催化剂在促进与燃料电池相关的清洁能源技术和减少二氧化碳排放方面的有效性。这项研究将与教学和推广工作相结合，强调众包工具和基于问题的学习原则，积极吸引学生和公民科学家参与创新清洁能源技术的产生和评估。该项目将专注于定义明确的平面电极，通过室温紫外线(UV)-臭氧工艺，在其上沉积超薄氧化硅和氧化钛层，从而实现纳米级的氧化厚度控制。氧化膜的厚度和表面化学性质将被调整，以控制活性物质的选择性传输和/或修改埋在界面上的独特催化位点。将使用一套成像和光谱学技术来研究定义良好的氧化物封装电催化剂用于酒精氧化和二氧化碳还原，这将使i.)传输和动力学效应的反褶积，ii.)阐明超薄氧化物覆盖层影响反应选择性的机制，以及iii.)开发可应用于广泛材料和反应的设计规则。实验测量将与合作者进行的数值模拟和密度泛函理论计算密切协调。本研究的一个重点是比较埋藏的氧化物/金属界面与氧化物/金属/电解质三相界面的催化性能。总的来说，所提出的研究将为合理设计稳定的氧化物封装电催化剂奠定基础，该催化剂能够高效和选择性地产生和使用燃料。除了具体的研究之外，该项目还将启动一项名为“能源创新众包”的倡议，该倡议将利用新兴的众包原则和在线工具来：(1)加快对当今学生的培训，使其成为未来能源技术的发明者和评估者；(2)增加对国家创新网络的参与；(3)提高学生和公众对尖端清洁能源技术的认识。该奖项反映了美国国家科学基金会的法定使命，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。

The project will investigate electrochemical catalysis on metal catalysts that are fully- or partially-covered by ultra-thin layers of porous materials. The coated catalysts will be evaluated for their effectiveness in promoting clean energy technologies related to fuel cells and reduction of carbon dioxide emissions. The research will be coupled with teaching and outreach efforts emphasizing crowdsourcing tools and problem-based learning principles that actively engage students and citizen scientists in the generation and evaluation of innovative clean energy technologies. The project will focus on well-defined planar electrodes on which ultra-thin overlayers of silicon oxide and titanium oxide will be deposited by a room temperature ultraviolet (UV)- Ozone process that allows for nanometer-level control of the oxide thickness. The thickness and surface chemistry of the oxide films will be tuned to control the selective transport of active species and/or modify the unique catalytic sites at the buried interface. The well-defined oxide-encapsulated electrocatalysts will be investigated for alcohol oxidation and carbon dioxide reduction using a suite of imaging and spectroscopy techniques that will enable i.) deconvolution of transport and kinetic effects, ii.) elucidation of the mechanisms by which ultrathin oxide overlayers influence reaction selectivity, and iii.) the development of design rules that can be applied across a wide range of materials and reactions. Experimental measurements will be closely coordinated with numerical modeling and density functional theory calculations performed by collaborators. A specific focus of this research is to compare the catalytic properties of buried oxide/metal interfaces to those at oxide/metal/electrolyte triple-phase boundary sites. Overall, the proposed research will lay the groundwork for the rational design of stable oxide-encapsulated electrocatalysts capable of highly efficient and selective generation and use of fuels. Beyond the specific research, the project will launch an initiative entitled "Crowdsourcing for Energy Innovation" that will leverage emerging crowdsourcing principles and online tools to i.) accelerate training of today's students to become the inventors and evaluators of tomorrow's energy technology, ii.) increase participation in the Nation's innovation network, and iii.) increase student and public awareness of cutting-edge clean energy technologies.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.