Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.
Chemistry Division, Brookhaven National Laboratory, Upton, NY, 11973, US.
Nat Commun. 2023 Jun 6;14(1):3273. doi: 10.1038/s41467-023-38928-1.
Size- and shape-tailored copper (Cu) nanocrystals can offer vicinal planes for facile carbon dioxide (CO) activation. Despite extensive reactivity benchmarks, a correlation between CO conversion and morphology structure has not yet been established at vicinal Cu interfaces. Herein, ambient pressure scanning tunneling microscopy reveals step-broken Cu nanocluster evolutions on the Cu(997) surface under 1 mbar CO(g). The CO dissociation reaction produces carbon monoxide (CO) adsorbate and atomic oxygen (O) at Cu step-edges, inducing complicated restructuring of the Cu atoms to compensate for increased surface chemical potential energy at ambient pressure. The CO molecules bound at under-coordinated Cu atoms contribute to the reversible Cu clustering with the pressure gap effect, whereas the dissociated oxygen leads to irreversible Cu faceting geometries. Synchrotron-based ambient pressure X-ray photoelectron spectroscopy identifies the chemical binding energy changes in CO-Cu complexes, which proves the characterized real-space evidence for the step-broken Cu nanoclusters under CO(g) environments. Our in situ surface observations provide a more realistic insight into Cu nanocatalyst designs for efficient CO conversion to renewable energy sources during C chemical reactions.
尺寸和形状适配的铜 (Cu) 纳米晶体可为易于二氧化碳 (CO) 激活提供共面晶面。尽管有广泛的反应性基准，但在共面 Cu 界面处，CO 转化率和形态结构之间尚未建立相关性。在此，常压扫描隧道显微镜揭示了在 1 毫巴 CO(g) 下 Cu(997)表面上的阶梯状 Cu 纳米团簇演变。CO 解离反应在 Cu 阶跃边缘产生一氧化碳 (CO) 吸附物和原子氧 (O)，导致 Cu 原子的复杂重构，以补偿常压下增加的表面化学势能。结合在配位不足的 Cu 原子上的 CO 分子有助于具有压力间隙效应的可逆 Cu 聚集，而解离的氧则导致不可逆的 Cu 晶面化几何形状。基于同步加速器的常压 X 射线光电子能谱确定了 CO-Cu 配合物中的化学结合能变化，这证明了 CO(g) 环境下阶梯状 Cu 纳米团簇的特征实空间证据。我们的原位表面观察为设计用于在 C 化学反应中有效将 CO 转化为可再生能源的 Cu 纳米催化剂提供了更现实的见解。
