中国科学院理化技术研究所吴骊珠团队报道了，冠醚修饰钴酞菁烷碳纳米管的单分子分散通过主客体相互作用实现强劲的CO₂还原。相关研究成果于2024年10月17日发表在《德国应用化学》。

将分子催化剂固定在导电载体（例如，多壁碳纳米管，CNTs）上是一种很有前景的方法，可以实现明确的催化剂/载体界面，这在催化转化方面表现出了可观的性能。然而，由于每种固定化分子催化剂的固有活性利用不足，特别是在适当电流密度的负载下，它们的全部潜力远未实现。

该文中，研究人员发现四冠醚取代的酞菁钴与金属离子（如K⁺离子）之间的主客体相互作用，这不仅消除了固定化过程中的催化剂聚集，而且在运行条件下通过额外的静电吸引增强了催化剂/载体的相互作用。

研究通过简单的浸涂程序，实现了单分子分散。这种催化剂/电极界面是稳定的，可以在所有负载条件下以几乎不变的周转频率（TOF）选择性催化CO₂转化为CO（＞96%），充分利用了负载型分子催化剂的固有活性。因此，在570mV的过电位下，在水性H型电解槽中同时实现了高TOF和高电流密度（在38mA/cm²下TOF为111s^-1）。

附：英文原文

Title: Single  Molecular Dispersion of Crown Ether-Decorated Cobalt Phthalocyanineon Carbon Nanotubes for Robust CO2 Reduction through Host-Guest Interactions

Author: Lei Zhu, Yi-Xuan Wang, Li-Juan Chen, Jian Li, Shuai Zhou, Qing-Qing Yang, Xu-Zhe Wang, Chen-Ho Tung, Li-Zhu Wu

Issue&Volume: 2024-10-17

Abstract: Immobilizing molecular catalysts on electro-conductive supports (for example, multi-walled carbon nanotubes, CNTs) represent a promising way to well-defined catalyst/support interfaces, which has shown appreciable performance for catalytic transformation. However, their full potential is far from achieved due to insufficient utilization of the intrinsic activity for each immobilized molecular catalyst, especially at loadings that should allow decent current densities. In the present work, we discover host-guest interaction between tetra-crown ether substituted cobalt phthalocyanine and metal ions, for example K+ ions, not only eliminate catalyst aggregation at immobilization procedures but also reinforce catalyst/support interactions by additional electrostatic attractions under operational conditions. Through simple dip-coating procedures, a successful single-molecular dispersion is achieved. Such a catalyst/electrode interface is stable and can selectively catalyze CO2-to-CO conversion (＞96%) with almost unchanged turnover frequency (TOF) at all loading conditions, which implies a full utilization of the intrinsic activity of supported molecular catalysts. Therefore, a simultaneous achievement of high TOF and high current density (TOF of 111 s-1 at 38 mA/cm2) is achieved, in an aqueous H-type electrolyzer at an overpotential of 570 mV.

DOI: 10.1002/anie.202418156

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202418156