中国科学院煤炭化学研究所覃勇团队揭示了铁亚纳米催化剂自旋控制核效应促进苯氧化。相关研究成果发表在2022年11月22日出版的《德国应用化学》。

从根本上理解核活性效应的性质对于合理设计具有低核活性的优良亚纳米催化剂非常重要，但这仍然是一个长期的挑战。

该文中，我们通过原子层沉积精确地合成了锚定在N，O共掺杂碳纳米棒（NOC）上的具有可调核活性的Fe亚纳米催化剂（Fe1–Fe4）。Fe亚纳米催化剂的电子性质和自旋构型依赖于核活性，并主导H₂O₂活化模式和Fe位点上活性O物种对C–H氧化的吸附强度。多重表征方法和DFT计算表明，Fe1–NOC单原子催化剂由于其独特的配位环境（Fe1N2O3）和中等自旋态（t2g4eg1），表现出最先进的苯氧化制苯酚活性，在25°C下产生407 h^–1的TOF，在60°C下未1869 h^–1，这是Fe二聚体的3.4、5.7和13.6倍，三聚体和四聚体催化剂。

附：英文原文

Title: Boosting Benzene Oxidation with a Spin-State-Controlled Nuclearity Effect on Iron Sub-Nanocatalysts

Author: Fanle Bu, Chaoqiu Chen, Yu Yu, Wentao Hao, Shichao Zhao, Yongfeng Hu, Yong Qin

Issue&Volume: 2022-11-22

Abstract: A fundamentally understanding the nature of nuclearity effects is very important for rational design of superior sub-nanocatalysts with low nuclearity but remains a long-standing challenge. Here, we have precisely synthesized Fe sub-nanocatalysts with tunable nuclearity (Fe1–Fe4) anchored on N, O-co-doped carbon nanorods (NOC) by atomic layer deposition. The electronic properties and spin configuration of the Fe sub-nanocatalysts are nuclearity-dependent and dominate the H2O2 activation modes and adsorption strength of active O species on Fe sites towards C–H oxidation. The Fe1–NOC single atom catalyst exhibits state-of-the-art activity for benzene oxidation to phenol ascribed to its unique coordination environment (Fe1N2O3) and medium spin state (t2g4eg1) supported by multifold characterization methods and DFT calculations, yielding TOF of 407 h–1 at 25°C and 1869 h–1 at 60°C, which is 3.4, 5.7 and 13.6 times higher than those of Fe dimer, trimer and tetramer catalysts, respectively.

DOI: 10.1002/anie.202216062

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202216062