Novel Catalysts for Electrochemical Carbon Dioxide Conversion: from Bimetallic Surfaces to Gas Diffusion Electrodes

弗吉尼亚大学的Giovanni Zangari教授获得了美国国家科学基金会化学部化学催化项目的奖金，他将研究新的电催化剂材料和旨在电化学减少二氧化碳的电极结构。二氧化碳加氢有望为实现燃料生产的碳中性循环提供一种灵活、有效的途径，对有效降低大气中二氧化碳浓度具有潜在的巨大重要性。虽然目前的催化剂存在选择性差、转化率低的问题，但具有横向成分梯度和可调吸附强度的双金属表面和表面合金对各种反应物和中间体具有广泛提高催化剂选择性和加速选定燃料形成的潜力。这些新型催化剂将通过电化学方法合成，并通过产物分析和反应机理的动力学研究来测试其催化活性和选择性。在接下来的阶段中，多孔纳米颗粒催化剂将被合成，并被离子液体浸渍，目的是增加催化剂表面的二氧化碳浓度，以提高其转化率。最后，将使用这些多孔纳米颗粒催化剂制备气体扩散电极，并开发合适的电极配置，以最大限度地提高电化学燃料的生产速度。拟议的研究目标是通过电化学转化为有用的液体燃料来降低大气中的二氧化碳浓度，这种燃料可能由可再生能源提供动力。通过开发能够加速二氧化碳转化的材料，本研究将对电化学过程中燃料形成的机制有一个基本的了解。这将使合理的催化剂设计和优化，以及提高过程的选择性。对不同电极配置的研究将有助于更好地了解二氧化碳在异质介质中的传输，从而优化反应器的整体性能。这里开发的知识不仅将促进二氧化碳回收新技术的广泛实施，而且有可能被转移到各种电化学转化过程中。此外，这项研究将为电化学和材料科学交叉领域的学生提供培训机会，以及一系列以环境问题为重点的教育活动，包括全校范围的研讨会和为本科生提供独特的实验室体验。

With this award from the Chemical Catalysis Program in the Chemistry Division at the National Science Foundation, Professor Giovanni Zangari of the University of Virginia will study new electrocatalyst materials and electrode configurations aimed at electrochemically reducing carbon dioxide. Hydrogenation of carbon dioxide is expected to provide a flexible, efficient route to the realization of a carbon neutral cycle for fuel production, potentially of enormous importance to effectively decrease carbon dioxide concentration in the atmosphere. While current catalysts suffer from poor selectivity and low conversion rates, bimetallic surfaces and surface alloys with lateral compositional gradients and tunable adsorption strength for the various reactants and intermediates have the potential to widely enhance catalyst selectivity and accelerate formation of selected fuels. These novel catalysts will be synthesized by electrochemical methods, and their catalytic activity and selectivity will be tested via product analysis and kinetic investigations of the reaction mechanism. In a successive stage, porous nanoparticle catalysts reproducing the optimized compositions identified previously will be synthesized and impregnated with ionic liquids with the objective of increasing carbon dioxide concentration at the catalytic surface to boost its conversion rate. Finally, gas diffusion electrodes will be fabricated using these porous nanoparticle catalysts and suitable electrode configurations will be developed with the aim of maximizing electrochemical fuel production rates.The proposed research targets the decrease of carbon dioxide concentration in the atmosphere via its electrochemical conversion to useful liquid fuels, potentially powered by renewable energy. By developing materials capable of accelerating carbon dioxide conversion, this research will develop a fundamental understanding of the mechanism of fuel formation by electrochemical processes. This will enable rational catalyst design and optimization as well as enhanced process selectivity. Investigation of various electrode configurations will provide a better insight on the transport of carbon dioxide through heterogeneous media, which could be used to optimize the overall reactor performance. The knowledge developed here will not only facilitate widespread implementation of new technologies for recycling of carbon dioxide, but has the potential to be transferred to a variety of electrochemical conversion processes. Additionally, this research will provide training opportunities for students at the intersection of electrochemistry and materials science, as well as an array of educational activities focused on environmental issues, including a university-wide seminar offering and unique laboratory experiences for undergraduates.