ITQ Instituto de Tecnología Química, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas (UPV-CSIC), Av. Los Naranjos s/n, 46022, Valencia, Spain.
Institute of Catalysis Research and Technology (IKFT), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz Platz 1, 76344, Eggenstein-Leopoldshafen, Germany.
Angew Chem Int Ed Engl. 2023 Jan 2;62(1):e202214048. doi: 10.1002/anie.202214048. Epub 2022 Nov 30.
A frontier challenge in single-atom (SA) catalysis is the design of fully inorganic sites capable of emulating the high reaction selectivity traditionally exclusive of organometallic counterparts in homogeneous catalysis. Modulating the direct coordination environment in SA sites, via the exploitation of the oxide support's surface chemistry, stands as a powerful albeit underexplored strategy. We report that isolated Rh atoms stabilized on oxygen-defective SnO uniquely unite excellent TOF with essentially full selectivity in the gas-phase hydroformylation of ethylene, inhibiting the thermodynamically favored olefin hydrogenation. Density Functional Theory calculations and surface characterization suggest that substantial depletion of the catalyst surface in lattice oxygen, energetically facile on SnO , is key to unlock a high coordination pliability at the mononuclear Rh centers, leading to an exceptional performance which is on par with that of molecular catalysts in liquid media.
在单原子（SA）催化中，一个前沿挑战是设计完全无机的位点，使其能够模拟均相催化中传统上与有机金属对应物不同的高反应选择性。通过利用氧化物载体的表面化学，调节 SA 位点的直接配位环境，是一种强大但尚未充分探索的策略。我们报告说，在氧缺陷的 SnO 上稳定的孤立 Rh 原子独特地将优异的 TOF 与气相乙烯氢甲酰化中的基本完全选择性结合在一起，抑制热力学上有利的烯烃加氢。密度泛函理论计算和表面表征表明，催化剂表面的晶格氧大量耗尽（在 SnO 上很容易实现）是在单核 Rh 中心实现高配位灵活性的关键，从而导致了一种卓越的性能，与液体介质中的分子催化剂相当。
