Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States.
Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, California 90095, United States.
Nano Lett. 2020 Dec 9;20(12):8719-8724. doi: 10.1021/acs.nanolett.0c03560. Epub 2020 Nov 17.
Gas-phase heterogeneous catalysis is a process spatially constrained on the two-dimensional surface of a solid catalyst. Here, we introduce a new toolkit to open up the third dimension. We discovered that the activity of a solid catalyst can be dramatically promoted by covering its surface with a nanoscale-thin layer of liquid electrolyte while maintaining efficient delivery of gas reactants, a strategy we call three-phase catalysis. Introducing the liquid electrolyte converts the original surface catalytic reaction into an electrochemical pathway with mass transfer facilitated by free ions in a three-dimensional space. We chose the oxidation of formaldehyde as a model reaction and observed a 25000-times enhancement in the turnover frequency of Pt in three-phase catalysis as compared to conventional heterogeneous catalysis. We envision three-phase catalysis as a new dimension for catalyst design and anticipate its applications in more chemical reactions from pollution control to the petrochemical industry.
气相多相催化是一种在固体催化剂二维表面上受到空间限制的过程。在这里，我们引入了一个新的工具包来开拓第三个维度。我们发现，通过在固体催化剂表面覆盖一层纳米级薄的液态电解质，同时保持气体反应物的有效输送，可以显著提高固体催化剂的活性，我们将这种策略称为三相催化。引入液态电解质将原始的表面催化反应转化为电化学途径，其中在三维空间中通过自由离子促进传质。我们选择甲醛氧化作为模型反应，与传统的多相催化相比，在三相催化中，Pt 的周转频率提高了 25000 倍。我们将三相催化视为催化剂设计的一个新维度，并预计其在从污染控制到石化工业等更多化学反应中的应用。
