EAGER: High-Efficiency and Cost-Effective Electrocatalysts for the Direct Conversion of Methane to Methanol at Ambient Conditions

页岩气矿床蕴藏着大量的天然气。将低密度天然气从偏远的页岩储藏地点运输到其使用点往往是不经济的，因此这些“搁浅的天然气”可能会在现场燃烧或燃烧以回收能源，从而绕过了运输的需要。增加这种国内能源供应的可获得性将降低燃料价格，增强能源安全，并减少这种资源的环境足迹。一种策略是从天然气中提取较大的燃料分子，并将它们压缩成易于运输的稠密液体。然而，天然气中的大部分是甲烷，这需要很高的能量才能压缩成液体。因此，一种很有前途的替代策略是将气态甲烷化学转化为液态甲醇。然而，使用已知的方法进行这种化学转化是极其困难的，而且页岩矿藏相对于化学制造设施来说位置偏远，这增加了挑战。该研究项目旨在开发新型的电化学催化剂，以更有效、更经济地将搁置的气态甲烷转化为液态甲醇。这种方法与可部署到远程位置的小型模块化制造单元兼容。本研究项目合理地利用电催化剂的表面取向和吸附原子修饰来促进甲烷电催化氧化制甲醇。人们正在探索金属催化剂的高指数面的使用以及氧化物载体上可移动的氧间隙的作用。使用Ni(310)和Ni(760)研究了高指数面降低甲烷吸附和部分氧化的活化势垒的可能性。利用原位傅里叶变换红外光谱与交流阻抗谱相结合的方法，研究了甲烷在活化化学吸附转化为吸附氢气和吸附甲基的过程中，表面小面、非化学计量比和吸附中心的作用。考虑到甲烷作为化学反应物的顽固性，这一过程的成功示范将增加使用搁浅甲烷的经济可行性，并减少巨大的国内能源供应对环境的影响。该研究项目还包括培养研究生和本科生。

Shale gas deposits contain enormous quantities of natural gas. Transporting low density natural gas from remote shale deposit locations to its point of use is often uneconomical, so this "stranded gas" may be flared or burned for energy recovery on site, circumventing the need for transport. Increasing the accessibility of this domestic energy supply would decrease fuel prices, increase energy security, and reduce the environmental footprint of this resource. One strategy is to extract the larger fuel molecules from natural gas, and compress them into an easily transportable dense liquid. The majority of natural gas is methane, though, which requires high energy to compress into liquid form. Thus, a promising alternative strategy is the chemical conversion of gaseous methane into liquid methanol. However, this chemical conversion is extremely difficult using known methods, and the remote location of the shale deposits relative to chemical manufacturing facilities increases the challenge. This research project seeks to develop novel electrochemical catalysts that will more efficiently, effectively, and economically convert stranded gaseous methane into liquid methanol. Such methods are compatible with small-scale, modular, manufacturing units that are deployable to remote locations. This research project rationalizes the use of surface orientation and adatom decoration of electrocatalysts to promote electrocatalytic oxidation of methane to methanol. The use of high-index facets of metallic catalysts and the role of mobile oxygen interstitials on oxide supports is being explored. The potential for higher-index planes to lower the activation barrier for methane adsorption and partial oxidation is being examined using Ni (310) and Ni (760). In-situ Fourier-transform infrared spectroscopy coupled with impedance spectroscopy is being used to probe the role of surface facets, nonstoichiometry, and adsorption sites in the activated chemisorption and transformation of methane to adsorbed hydrogen and adsorbed methyl. Given the recalcitrance of methane as a chemical reactant, successful demonstration of this process would increase the economic feasibility of using stranded methane and reduce the environmental impact of a vast domestic energy supply. The research project also involves training both graduate and undergraduate students.