Prabhakar Reddy Kasala, Lim Hojoon, Islam Arephin, Tian Yi, Hunt Adrian, Waluyo Iradwikanari, Rodriguez José A
Chemistry Division, Brookhaven National Laboratory, Upton, New York 11973, United States.
National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973, United States.
ACS Appl Mater Interfaces. 2025 Jun 25;17(25):36810-36820. doi: 10.1021/acsami.5c07344. Epub 2025 Jun 16.
The direct conversion of carbon dioxide (CO) into methanol via hydrogenation is essential for industrial applications. Recent studies on catalysts that contain an inverse oxide/metal configuration have shown very good catalytic performance for the CO hydrogenation to methanol process. In this study, we investigated the behavior of indium oxide-Cu(111) interfaces under pure CO and CO/H mixtures by using synchrotron-based ambient-pressure X-ray photoelectron spectroscopy (AP-XPS). Initially, a single layer of copper oxide (CuO) was grown on the Cu(111) surface by controlled oxidation. On this surface, indium was deposited at room temperature. Oxygen atoms are transferred from CuO/Cu(111) to the indium metal upon deposition, forming In-O-Cu bonds and active interfaces. Although Cu(111) is not very active for the binding and activation of CO, the formed InO-Cu(111) interfaces had no problem adsorbing and dissociating the molecules at room temperature. The reaction of CO with H on InO-Cu(111) yielded surface-bound HCO, CO, CO, and CH species, which are typical intermediates in the production of methanol and other oxygenates. The InO-Cu(111) interface underwent dynamic chemical changes under reaction conditions, forming In-Cu alloys at low indium coverages (<0.05 monolayer), while at higher indium coverages, a mixture of In-Cu and InO was detected in XPS. These findings indicate that InO/In-Cu interfaces can play a key role in processes aimed at the trapping and valorization of CO.
通过氢化将二氧化碳（CO₂）直接转化为甲醇对于工业应用至关重要。最近对具有反相氧化物/金属构型的催化剂的研究表明，其在CO₂加氢制甲醇过程中具有非常好的催化性能。在本研究中，我们使用基于同步加速器的常压X射线光电子能谱（AP-XPS）研究了纯CO₂和CO₂/H₂混合物下氧化铟-Cu(111)界面的行为。最初，通过控制氧化在Cu(111)表面生长单层氧化铜（CuO）。在该表面上，室温下沉积铟。沉积时，氧原子从CuO/Cu(111)转移到铟金属上，形成In-O-Cu键和活性界面。尽管Cu(111)对CO₂的吸附和活化活性不高，但形成的InO-Cu(111)界面在室温下能够吸附和解离这些分子。CO₂与H₂在InO-Cu(111)上反应生成表面结合的HCO、CO、CO₂和CHₓ物种，这些是甲醇和其他含氧化合物生产中的典型中间体。InO-Cu(111)界面在反应条件下经历动态化学变化，在低铟覆盖度（<0.05单层）下形成In-Cu合金，而在较高铟覆盖度下，XPS检测到In-Cu和InO的混合物。这些发现表明，InO/In-Cu界面在旨在捕获和利用CO₂的过程中可以发挥关键作用。
