Department of Chemical Engineering, Stanford University, Stanford, CA 94305.
SUNCAT Center for Interface Science and Catalysis, Stanford University, Stanford, CA 94305.
Proc Natl Acad Sci U S A. 2022 Feb 15;119(7). doi: 10.1073/pnas.2114768119.
The conversion of CO into fuels and chemicals is an attractive option for mitigating CO emissions. Controlling the selectivity of this process is beneficial to produce desirable liquid fuels, but C-C coupling is a limiting step in the reaction that requires high pressures. Here, we propose a strategy to favor C-C coupling on a supported Ru/TiO catalyst by encapsulating it within the polymer layers of an imine-based porous organic polymer that controls its selectivity. Such polymer confinement modifies the CO hydrogenation behavior of the Ru surface, significantly enhancing the C production turnover frequency by 10-fold. We demonstrate that the polymer layers affect the adsorption of reactants and intermediates while being stable under the demanding reaction conditions. Our findings highlight the promising opportunity of using polymer/metal interfaces for the rational engineering of active sites and as a general tool for controlling selective transformations in supported catalyst systems.
将 CO 转化为燃料和化学品是缓解 CO 排放的一种有吸引力的选择。控制这个过程的选择性有利于生产所需的液体燃料，但 C-C 偶联是反应中的一个限制步骤，需要高压。在这里，我们提出了一种在负载型 Ru/TiO 催化剂上通过将其封装在基于亚胺的多孔有机聚合物的聚合物层中来有利于 C-C 偶联的策略，该聚合物层控制其选择性。这种聚合物限制改变了 Ru 表面的 CO 加氢行为，使 C 的生成周转频率显著提高了 10 倍。我们证明了聚合物层在苛刻的反应条件下稳定的同时，影响了反应物和中间体的吸附。我们的研究结果突出了利用聚合物/金属界面来合理设计活性位点的有前途的机会，并将其作为控制负载催化剂体系中选择性转化的通用工具。
