利用FeN4对缺陷Cu1.81S进行电子调控实现高性能硝基芳烃加氢反应
发布时间:2025-12-09
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一、研究背景:
催化加氢是化学工业中的关键转化过程。硝基芳烃加氢生成芳香胺,这些芳香胺广泛应用于制药、染料和弹性体领域。虽然贵金属催化剂在非均相硝基芳烃加氢反应具有很高的活性,但高昂的成本限制了其大规模应用。因此,在过去十年中,基于Fe、Co、Ni和Cu的非贵金属催化剂得到了广泛的研究。其中,Fe和Cu因其储量丰富、成本低和毒性低而备受关注。然而,铁基催化剂的性能仍不足以满足工业应用需求。相比之下,铜基催化剂引起了人们的极大关注;一些铜基催化剂已在气相加氢反应中得到了广泛的工业应用。然而,铜基催化剂在气-液-固体系中的催化性能较差。主要原因是,铜或含铜纳米颗粒活化分子氢的能力较差,并且H2解离具有极高的能垒。这种缺陷主要是由于其电子结构的固有惰性,严重限制了它们在气液固加氢反应中的广泛应用。过去十年间,尽管对铜基催化剂的研究一直活跃,但性能提升缓慢,至今尚未取得公认的突破性进展。因此,调控铜基催化剂的电子结构从而调节其加氢性能的策略具有重要意义,但也极具挑战性。
二、文章简介:
1. 形貌与结构表征
Figure 1. (a) Schematic illustration of the preparation of Cu1.81S/Fe1@PC catalyst. (b) Scanning electron microscopy (SEM) and (c, d) transmission electron microscopy image of Cu1.81S/Fe1@PC. (e) High-resolution Transmission electron microscopy (HR-TEM) images of individual Cu1.81S nanocrystals, and the inset presents their lattice stripes. (f) Aberration corrected, high-angle annular dark-field scanning transmission electron microscopy (AC-HAADF-STEM) images of Cu1.81S/Fe1@PC. (g) HR-TEM images and elemental distribution maps of Cu1.81S/Fe1@PC.
Figure 2. (a) X-ray Diffraction of Cu1.81S/Fe1@PC and the contrasting catalysts. (b) XPS spectra of Cu 2p for Cu1.81S/Fe1@PC, Cu1.81S/Fe@PC. (c and e) Fe, Cu K-edge XANES spectra and (d and f) Fe, Cu K-edge k2-weight FTEXAFS spectra of Cu1.81S/Fe1@PC and reference samples. WT of EXAFS signals from (g) Cu1.81S/Fe1@PC and (h) reference samples.
2. Cu1.81S/Fe1@PC催化硝基芳烃加氢的性能
Figure 3. (a) Catalytic performance of different catalysts in p-CNB hydrogenation. (b) Effect of Fe loading on p-CNB hydrogenation. (c) Effect of Cu loading on p-CNB hydrogenation. Reaction conditions: 0.38 mmol p-CNB in 10 mL of solvent (H2O: EtOH=1:1,V/V) by using 20 mg of a catalyst, reaction for 6 h under 10 bar H2 at 120 oC.
3.FeN4与Cu1.81S纳米颗粒的协同催化效应
Figure 4. (a) Catalytic performance for nitrobenzene hydrogenation of corresponding kinetic curves and activation energy. (b) Effect of hydrogen pressure on the initial rate of catalytic reaction. Reaction conditions: 0.38 mmol p-CNB using 20 mg of catalyst in 10 mL of solvent (H2O: EtOH=1:1, V/V) at 120 °C under 10 bar H2 or D2. (c) Isotopic effects of Cu1.81S/Fe1@PC and Cu1.81S@PC in hydrogenation catalysis. (d–f) In-situ DRIFT of p-CNB hydrogenation based on Fe1@PC, Cu1.81S@PC, and Cu1.81S/Fe1@PC catalysts.
4. FeN4与Cu1.81S纳米颗粒协同作用机理
Figure 5. (a) Charge density difference distribution of catalysts. (b) Bader charge occupancy analysis of Catalysts. (c) The adsorption and dissociation energies of H2 on different active sites on Catalysts. (d) Electron localization function (ELF) of Catalysts.
通过蛋白质-金属离子网络的两步热解法,制备了负载于多孔碳上的Cu1.81S/Fe1@PC催化剂,该催化剂集成了FeN4和缺陷工程化的Cu1.81S。在温和条件下,该催化剂在硝基芳烃加氢反应中实现了芳香胺的高收率(>95%)。光谱分析表明,由于Fe-N4与Cu1.81S的相互作用,提高了Cu的氧化态。动力学和DFT计算结果表明,H2活化途径具有协同效应:Cu1.81S中的缺陷介导了异裂,而Fe-N4进一步调节了电子密度,从而降低了H2的解离势垒,从Cu1.81S@PC的0.67 eV降低到Cu1.81S/Fe1@PC的0.27 eV,进而提高了催化活性。这些结果表明,在温和条件下释放铜基催化剂对硝基化合物的催化活性是可行的,并为催化剂设计中不同活性位点类型的空间耦合策略提供了新的见解。
点击文末「阅读原文」,直达文献。 Authors: Zhenxing Ren, Lizhen Lian, Xingle Zuo, Xinkang Cui, Min Zhang, Liu Deng, Liqiang Wang,* and YouNian Liu* Title: Electronically Modulated Defective Cu1.81S by FeN4 for High‐Performance Nitroarene Hydrogenation Published in: Advanced Functional Materials, doi: 10.1002/adfm.202524811
