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
·
材料科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Siying Chong,Shuang Zhao,Jiaoyan Li,Gangwei Huang,Yajing Zhang,Ruirui Liu,Kangjun Wang
Gas-phase dehydrocyclization of biomass-derived 1,4-butanediol (BDO) to γ-butyrolactone (GBL) is a sustainable and environmentally friendly process conducted at atmospheric pressure. In the present work, a series of 15Cu/xMgO-yCeO 2 catalysts with different MgO: CeO 2 ratios were prepared by the ammonia vaporization method. The gas-phase dehydrocyclization of BDO to GBL was carried out over these Cu-based catalysts synthesized in a fixed-bed reactor. The physicochemical properties of the catalysts were investigated by XRD, SEM, TEM, FTIR, N 2 isothermal adsorption–desorption, H 2 -TPR, CO 2 -TPD, Raman, XPS, and EPR. The results indicated that the 15Cu/10MgO-90CeO 2 catalyst exhibited a smaller particle size, higher specific surface area, and increased oxygen vacancies than the 15Cu/CeO 2 catalyst. Operating conditions of 240 °C reaction temperature, 2.4 mL/h space velocity, and 98.92 % GBL yield from BDO dehydrogenation were achieved under 40 mL/min N 2 flow for 4 h. Density functional theory (DFT) calculations confirmed that the 15Cu/10MgO-90CeO 2 catalyst with more oxygen vacancies was more favorable for the adsorption and activation of BDO on the catalyst surface than 15Cu/CeO 2 , and its higher catalytic activity was attributed to the synergistic interaction between Cu + and oxygen vacancies on the catalyst surface.
研究领域:
催化化学
·
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2022
·Vol. 10
·期 13
·7300-7313
·
IF 14.511
Zhao Sun,Junpeng Liu,Rongjun Zhang,Yu Wu,Hongwei Li,Sam Toan,Zhiqiang Sun
Sorption-enhanced steam reforming of methanol (SE-SRM) is a promising approach to creating a high-purity hydrogen supply. However, catalysts suffer from activity deactivation and low CO2 uptake capacity. In this study, we investigate the role of Ga doping of Cu–MgO in SE-SRM by synthesizing a series of MgO embedded xGaCuMg catalytic sorbents via a sol–gel method. The TEM-EDX mapping results indicate that MgO nanoparticles can be successfully embedded in the bulk-phase of the catalytic sorbent with a stabilized microstructure. The results from in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) reveal that the Ga-doped catalytic sorbent is conducive to promoting the conversion of C-containing intermediates in SE-SRM, and absorbing CO2 in the form of bidentate carbonate rather than monodentate carbonate. Experimental studies verify that the best uptake capacity of 18GaCuMg catalytic sorbent (36.25 mg CO2/g MgO) achieves almost complete conversion of methanol (99.70%) with 100% H2 selectivity at 200 °C. Specifically, no CO is formed during the kinetic-control stage of SE-SRM. Density functional theory (DFT) calculations based on the Cu(111)Ga2O3(202)MgO(200) model revealed that the Ga doping can enhance the adsorption energies of methanol and carbon dioxide, promoting methanol activation and increasing CO2 uptake capacity. These findings provide valid strategies for functionalized nanomaterial design, which will substantially promote the SE-SRMR performance with desired catalytic sorbent recyclability.
研究领域:
材料科学
·
催化化学
·
能源工程
✓ 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
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2026
·
IF 9.2
Jiaoyan Li,Tianyu Li,Kun Sun,Junhao Chang,Peng Zheng,Yajing Zhang,Fangke Wang,Kangjun Wang
EMSI enhances FFA ring-opening hydrogenolysis to 1,2-PeD. • Electron-deficient Cu species and basic sites synergistically activate C–O bonds. • In situ ATR-FTIR reveals furan-ring opening and C 5 intermediate formation. • DFT reveals furan-O adsorption promotes C 5 –O 1 bond polarization and cleavage. Selective hydrogenolysis of furfuryl alcohol (FFA) to 1,2-pentanediol (1,2-PeD) offers a route for biomass valorization. However, catalysts suffer from unclear active-site configurations and insufficient activation of the key C–O bond. To address this, a Cu/MgO catalyst featuring basic sites and electron-deficient Cu active sites at the interface is developed. Compared with Cu/Al 2 O 3 and Cu/CeO 2 , Cu/MgO achieves 97% FFA conversion and 45% 1,2-PeD selectivity under continuous-flow conditions at 140 °C and 6 MPa H 2 . In situ XPS, in situ ATR-FTIR, and DFT calculations indicate that electronic metal-support interaction (EMSI) at the Cu–MgO interface induces interfacial charge redistribution and favors ring-opening hydrogenolysis. The resulting electron-deficient Cu species and MgO-derived basic sites cooperatively promote FFA adsorption through the furan-ring oxygen, C–O bond activation, C 5 carbonyl intermediate formation, and hydrogenation to 1,2-PeD. This work addresses the mechanistic gap between EMSI and the ring-opening hydrogenolysis of FFA over Cu–MgO catalysts. Cu–MgO interfacial sites, where EMSI generates electron-deficient Cu species while MgO provides basic sites, enable selective ring-opening hydrogenolysis of furfuryl alcohol to 1,2-pentanediol. Preferential adsorption through the furan-ring O atom positions the C 5 –O 1 bond near the Cu–MgO interface, promoting interfacial polarization, selective C–O bond cleavage, C 5 carbonyl intermediate formation, and subsequent hydrogenation to 1,2-pentanediol, as supported by in situ XPS, in situ ATR-FTIR, and DFT calculations. Download: Download high-res image (331KB) Download: Download full-size image
✓ 已验证
DOI
高影响因子
Molecular Catalysis
·
2017
·
IF 0
Hao Chen,Houhang Ruan,Xilei Lu,Jie Fu,Timothy Langrish,Xiuyang Lu
Catalytic transfer hydrogenation of furfural to furfuryl alcohol is considered to be a very important industrial process. In this work, non-noble Cu supported on MgO-Al 2 O 3 catalysts have been prepared by co-precipitation and have shown excellent catalytic performance for conversion of furfural to furfuryl alcohol in near-critical iso-propanol. The effects of the Cu state (reduction degree and dispersion) and loading in Cu/MgO-Al 2 O 3 , acidity of catalysts have been investigated by X-ray diffraction (XRD), coupled plasma optical emission spectrometry (ICP-OES), N 2 adsorption and desorption (N 2 -BET) and temperature-programmed desorption of ammonia (NH 3 -TPD), which have led to high activity for producing furfuryl alcohol. The results have shown that the selectivity of furfuryl alcohol has been influenced by the Cu state, Lewis acidity, reaction temperature and reaction time. The mechanisms, Lewis acid- and metal mediated hydrogenation, have shown that a desirable balance of Cu loading and Lewis acidity of catalyst has influenced the activity significantly. Almost 100% furfural conversion, with 89.3% furfuryl alcohol yield has been obtained. Cycling tests have shown that the prepared catalysts have been stable, where recycling the catalysts at least four times has not shown any reduction in activity.
研究领域:
化学工程
·
催化材料
✓ 已验证
DOI
危险品化学品经营许可证（带存储）