ACS Catalysis
·
2024
·
IF 11.3
Mei-Yao Wu,Shan-Qing Li,Wei-Wei Wang,Chun-Jiang Jia
The structures of active components in practical solid catalysts are seldom homogeneous, which makes it challenging to explore the synergistic effect among the complex catalyst components in heterogeneous catalysis. The active structure of Cu-based catalysts, which are widely used in water gas shift reactions and other important industrial reactions, has been debated. This work prepared Cu–MgO catalysts with the copresence of Cu particles and Cu atoms to investigate the synergistic effects of these Cu species. We found that the Cu nanoparticles served to adsorb and activate the reactant molecule of CO, while the atomic Cu species at the surface of the MgO lattice might exist as the Mg2Cu2–Ov site for water dissociation. The presence of surface-substituted Cu atoms modulated the reactivity of adjacent oxygen vacancy in the MgO surface, enhanced the ability of H2O dissociation to form reactive –OH species, and allowed the oxygen vacancies to recycle, contributing to the continuation of the reaction. A volcano-type relation of catalytic performance versus Cu0/Cu2+ ratio has been established, revealing the existence of synergy between Cu particles and Cu atoms. In addition, due to this synergistic effect, the optimized Cu–MgO catalyst shows a very high activity with a CO conversion rate of 1119 μmolCO gCu–1 s–1 at 300 °C. This work revealed the synergistic effect of different Cu species in the Cu–MgO catalysts, which was important for unraveling the contribution of complex components to catalytic performance.
研究领域:
催化化学
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材料科学
✓ 已验证
DOI
高影响因子
Reaction Kinetics Mechanisms and Catalysis
·
2014
·Vol. 111
·期 2
·633-645
·
IF 0.983
Yue Chuan-Jun,Gu Li-Ping,Su Yang,Zhu Shao-Ping
Cu/MgO and MgO nested on the surface of Raney Cu were prepared by a wet-mixing method and used as catalyst for glycerol hydrogenolysis. The texture of Raney Cu/MgO was characterized by X-ray diffraction and transmission electron microscopy, Brunauer–Emmett–Teller, and CO 2 -temperature-programmed desorption techniques. Results indicated that MgO was well dispersed in the pores of Raney Cu. Moreover, Raney Cu with large specific surface area had a larger contact surface for MgO, and a new phase of Cu–MgO was produced. Glycerol hydrogenolysis was selectively catalyzed under the synergistic effect of Cu and MgO in Cu/MgO catalyst. Under the moderate conditions of 180 °C and 1 MPa H 2 , the conversion of glycerol was 36.2 wt% and the selectivity for 1,2-propanediol was ~85 wt% when chemical equilibrium.
研究领域:
化学工程
·
催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
Nano Energy
·
2025
·
IF 17.1
Zhao Sun,Huicai Wang,Xingxu Wang,Riguang Zhang,Zhiqiang Sun
Sorption-enhanced steam reforming of methanol (SE-SRM) offers a promising route for high-quality hydrogen production with in situ CO 2 capture; however, achieving an optimal balance between catalytic activity and CO 2 uptake capability, while ensuring catalyst stability, remains a significant challenge. In this study, a series of Zr-doped (0 wt%, 5 wt%, 15 wt%, 25 wt%) Cu-MgO catalytic sorbents are synthesized for SE-SRM. At 180℃, the hydrogen concentration and yield reach nearly 100 % and 10.35 μmol·g −1 ·s −1 . Moreover, the catalytic sorbent basically retains its catalytic activity and CO 2 uptake capacity after 30 cycles with merely slight deactivation. Results demonstrate that the doped Zr, presents as tetragonal ZrO 2 , enhances metal-support interactions with the formation of a Cu-O-Zr interfacial structure, promoting Cu nanocluster dispersion and altering the Cu + /Cu 0 distributions. Zr doping also enables the modulation of the medium-strong basic sites. Moreover, the AFM and TEM confirmed the formation of high-roughness MgO surface on the substrate, thereby facilitating CO 2 diffusion and adsorption. DFT calculation results further confirm the advantages of Zr-doped Cu-MgO catalytic sorbents due to its stronger capability on CH 3 OH activation and CO 2 adsorption.
研究领域:
催化化学
·
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2023
·
IF 4.7
Kai Sun,Yuewen Shao,Cong Ming,Mengjiao Fan,Huailin Fan,Lijun Zhang,Shu Zhang,Yi Wang,Guozhu Chen,Xun Hu
Impregnation is a traditional method for preparing heterogeneous catalysts, which typically includes impregnation, calcination and reduction steps. In this study, catalyst preparation was combined with its use in catalytic hydrogenation for avoiding ex-situ catalyst-synthesis. Specifically, Cu/MgO were prepared by simply mixing CuSO 4 , MgO and the reactant to be hydrogenated such as levulinic acid (LA) or ethyl levulinate (EL) in ethanol with hydrogen. Heating of the mixture to 160 °C could obtain both synthesized Cu/MgO and hydrogenation product of gamma-valerolactone (GVL) (highest yield: 99.9%). The formation of Cu/MgO catalyst proceeded via the steps of fixing Cu 2+ by reacting with the basic sites of MgO to form Cu(OH) 2 . The metastable Cu(OH) 2 decomposed to form CuO that was reduced to Cu for catalyzing conversion of LA/EL to GVL. Such a method is very simple and applicable to prepare varied types of Cu-based catalyst by changing copper salts and supports of varied alkalinity.
研究领域:
催化
·
化学工程
·
可再生能源
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）