MOFs-Derived Zn-Based Catalysts in Acetylene Acetoxylation

Metal–organic frameworks (MOFs)-derived materials with a large specific surface area and rich pore structures are favorable for catalytic performance. In this work, MOFs are successfully prepared. Through pyrolysis of MOFs under nitrogen gas, zinc-based catalysts with different active sites for acetylene acetoxylation are obtained. The influence of the oxygen atom, nitrogen atom, and coexistence of oxygen and nitrogen atoms on the structure and catalytic performance of MOFs-derived catalysts was investigated. According to the results, the catalysts with different catalytic activity are Zn-O-C (33%), Zn-O/N-C (27%), and Zn-N-C (12%). From the measurements of X-ray photoelectron spectroscopy (XPS), it can be confirmed that the formation of different active sites affects the electron cloud density of zinc. The electron cloud density of zinc affects the ability to attract CH3COOH, which makes catalysts different in terms of catalytic activity.

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Inverse relationship of dimensionality and catalytic activity in CO2transformation: a systematic investigation by comparing multidimensional metal–organic frameworks

Journal of Materials Chemistry A ◽

10.1039/c7ta04004k ◽

2017 ◽

Vol 5 (30) ◽

pp. 15961-15969 ◽

Cited By ~ 29

Author(s):

Robin Babu ◽

Roshith Roshan ◽

Yeongrok Gim ◽

Yun Hee Jang ◽

Jintu Francis Kurisingal ◽

...

Keyword(s):

Catalytic Activity ◽

Active Sites ◽

Inverse Relationship ◽

Metal Organic Frameworks ◽

Catalytic Performance ◽

Systematic Investigation ◽

Cycloaddition Reactions ◽

Metal Organic ◽

Relationship Of

The correlation between dimensionality and active sites on deciding the catalytic performance of an MOF catalyst in CO2–epoxide cycloaddition reactions has been studied.

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Capping Agent Effect on Pd-Supported Nanoparticles in the Hydrogenation of Furfural

Catalysts ◽

10.3390/catal10010011 ◽

2019 ◽

Vol 10 (1) ◽

pp. 11 ◽

Cited By ~ 3

Author(s):

Shahram Alijani ◽

Sofia Capelli ◽

Stefano Cattaneo ◽

Marco Schiavoni ◽

Claudio Evangelisti ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Active Sites ◽

Catalytic Performance ◽

Shielding Effect ◽

Capping Agents ◽

X Ray ◽

Supported Nanoparticles ◽

Liquid Phase Hydrogenation ◽

Diallyldimethylammonium Chloride ◽

Transmission Electron

The catalytic performance of a series of 1 wt % Pd/C catalysts prepared by the sol-immobilization method has been studied in the liquid-phase hydrogenation of furfural. The temperature range studied was 25–75 °C, keeping the H2 pressure constant at 5 bar. The effect of the catalyst preparation using different capping agents containing oxygen or nitrogen groups was assessed. Polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), and poly (diallyldimethylammonium chloride) (PDDA) were chosen. The catalysts were characterized by ultraviolet-visible spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The characterization data suggest that the different capping agents affected the initial activity of the catalysts by adjusting the available Pd surface sites, without producing a significant change in the Pd particle size. The different activity of the three catalysts followed the trend: PdPVA/C > PdPDDA/C > PdPVP/C. In terms of selectivity to furfuryl alcohol, the opposite trend has been observed: PdPVP/C > PdPDDA/C > PdPVA/C. The different reactivity has been ascribed to the different shielding effect of the three ligands used; they influence the adsorption of the reactant on Pd active sites.

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Mechanosynthesis of new azine-functionalized Zn(ii) metal–organic frameworks for improved catalytic performance

Journal of Materials Chemistry A ◽

10.1039/c4ta04001e ◽

2014 ◽

Vol 2 (40) ◽

pp. 16863-16866 ◽

Cited By ~ 89

Author(s):

Mohammad Yaser Masoomi ◽

Saeideh Beheshti ◽

Ali Morsali

Keyword(s):

Catalytic Activity ◽

Metal Organic Frameworks ◽

Catalytic Performance ◽

Metal Organic

Functionalization of MOF pore walls with azine groups enables greater interaction between the walls and substrate molecules, thereby increasing catalytic activity of the MOFs.

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Defective Pt nanoparticles encapsulated in mesoporous metal–organic frameworks for enhanced catalysis

Chemical Communications ◽

10.1039/c8cc04485f ◽

2018 ◽

Vol 54 (64) ◽

pp. 8822-8825 ◽

Cited By ~ 14

Author(s):

Qiang Wang ◽

Xu-Sheng Wang ◽

Chun-Hui Chen ◽

Xue Yang ◽

Yuan-Biao Huang ◽

...

Keyword(s):

Catalytic Activity ◽

Active Sites ◽

Metal Organic Frameworks ◽

Pt Nanoparticles ◽

Mild Conditions ◽

Metal Organic ◽

Mesoporous Metal ◽

First Time

Highly ultrafine defective Pt nanoparticles (NPs) encapsulated in the mesopores of MIL-101 (Pt(Co)@MIL-101) were achieved for the first time through a chemical dealloying approach. The obtained material could provide more active sites to contact reactants and showed superior catalytic activity towards the hydrogenation of nitroarenes under mild conditions.

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A Facile Method for Preparing UiO-66 Encapsulated Ru Catalyst and its Application in Plasma-Assisted CO2 Methanation

Nanomaterials ◽

10.3390/nano9101432 ◽

2019 ◽

Vol 9 (10) ◽

pp. 1432 ◽

Cited By ~ 7

Author(s):

Weiwei Xu ◽

Mengyue Dong ◽

Lanbo Di ◽

Xiuling Zhang

Keyword(s):

Electron Microscopy ◽

Catalytic Activity ◽

Photoelectron Spectroscopy ◽

Gas Flow ◽

Structural Integrity ◽

Metal Organic Framework ◽

Step Method ◽

Co2 Methanation ◽

X Ray ◽

Metal Organic

With increasing applications of metal-organic frameworks (MOFs) in the field of gas separation and catalysis, the preparation and performance research of encapsulating metal nanoparticles (NPs) into MOFs (M@MOF) have attracted extensive attention recently. Herein, an Ru@UiO-66 catalyst is prepared by a one-step method. Ru NPs are encapsulated in situ in the UiO-66 skeleton structure during the synthesis of UiO-66 metal-organic framework via a solvothermal method, and its catalytic activity for CO2 methanation with the synergy of cold plasma is studied. The crystallinity and structural integrity of UiO-66 is maintained after encapsulating Ru NPs according to the X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). As illustrated by X-ray photoelectron spectroscopy (XPS), high resolution transmission electron microscopy (HRTEM), and mapping analysis, the Ru species of the hydration ruthenium trichloride precursor are reduced to metallic Ru NPs without additional reducing processes during the synthesis of Ru@UiO-66, and the Ru NPs are uniformly distributed inside the Ru@UiO-66. Thermogravimetric analysis (TGA) and N2 sorption analysis show that the specific surface area and thermal stability of Ru@UiO-66 decrease slightly compared with that of UiO-66 and was ascribed to the encapsulation of Ru NPs in the UiO-66 skeleton. The results of plasma-assisted catalytic CO2 methanation indicate that Ru@UiO-66 exhibits excellent catalytic activity. CO2 conversion and CH4 selectivity over Ru@UiO-66 reached 72.2% and 95.4% under 13.0 W of discharge power and a 30 mL·min−1 gas flow rate ( V H 2 : V C O 2 = 4 : 1 ), respectively. Both values are significantly higher than pure UiO-66 with plasma and Ru/Al2O3 with plasma. The enhanced performance of Ru@UiO-66 is attributed to its unique framework structure and excellent dispersion of Ru NPs.

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Effect of Direct Reduction Treatment on Pt–Sn/Al2O3 Catalyst for Propane Dehydrogenation

Catalysts ◽

10.3390/catal9050446 ◽

2019 ◽

Vol 9 (5) ◽

pp. 446 ◽

Cited By ~ 7

Author(s):

Jae-Won Jung ◽

Won-Il Kim ◽

Jeong-Rang Kim ◽

Kyeongseok Oh ◽

Hyoung Lim Koh

Keyword(s):

Catalytic Activity ◽

Photoelectron Spectroscopy ◽

Direct Reduction ◽

Coke Formation ◽

Catalytic Performance ◽

Propane Dehydrogenation ◽

X Ray ◽

Transmission Electron ◽

Calcination Step ◽

Xrd Patterns

Pt–Sn/Al2O3 catalysts were prepared by the direct reduction method at temperatures from 450 to 900 °C, denoted as an SR series (SR450 to SR900 according to reduction temperature). Direct reduction was performed immediately after catalyst drying without a calcination step. The activity of SR catalysts and a conventionally prepared (Cal600) catalyst were compared to evaluate its effect on direct reduction. Among the SR catalysts, SR550 showed overall higher conversion of propane and propylene selectivity than Cal600. The nano-sized dispersion of metals on SR550 was verified by transmission electron microscopy (TEM) observation. The phases of the bimetallic Pt–Sn alloys were examined by X-ray diffraction, TEM, and energy dispersive X-ray spectroscopy (EDS). Two characteristic peaks of Pt3Sn and PtSn alloys were observed in the XRD patterns, and these phases affected the catalytic performance. Moreover, EDS confirmed the formation of Pt3Sn and PtSn alloys on the catalyst surface. In terms of catalytic activity, the Pt3Sn alloy showed better performance than the PtSn alloy. Relationships between the intermetallic interactions and catalytic activity were investigated using X-ray photoelectron spectroscopy. Furthermore, qualitative analysis of coke formation was conducted after propane dehydrogenation using differential thermal analysis.

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Facile Fabrication of Nanosized Nickel Powder via Solid-State Reaction at Low Heat and its Catalytic Performance

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.393-395.1235 ◽

2011 ◽

Vol 393-395 ◽

pp. 1235-1241

Author(s):

Liu Hong ◽

Wu Bin ◽

Feng Cheng Tao ◽

Qin Xia

Keyword(s):

Catalytic Activity ◽

Solid State ◽

Solid State Reaction ◽

Photoelectron Spectroscopy ◽

Catalytic Performance ◽

X Ray ◽

Nickel Powders ◽

Transmission Electron ◽

Raney Ni ◽

Facile Fabrication

Nano-Nickel (Ni0) powders have been successfully prepared via the reduction of nanosized NiO powders by the solid state reaction. And the nanosized NiO powders were derived from low temperature (350°C) calcinations in muffle in air of nanosized Ni(OH)2 powders firstly prepared by the room temperature solid state reaction between NiSO4•6H2O and NaOH by H2 at 400°C for 4 h. The crystallinity, microstructure of surface and xps property of obtained nickel powders were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). Furthermore, the catalytic activity of the obtained nanosized Ni powders for hydrogenation of nitrobenzene to aniline was investigated. The results show that the spherical Ni parepared in particle sizes ranges from 20 to 25 nm and achieves enhanced catalytic activity for hydrogenation of nitrobenzene to aniline compared with Raney Ni.

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Activation of Peroxymonosulfate by CuNi@C Derived from Metal–Organic Frameworks Precursor

Australian Journal of Chemistry ◽

10.1071/ch18260 ◽

2018 ◽

Vol 71 (11) ◽

pp. 874 ◽

Cited By ~ 2

Author(s):

Xue Huang ◽

Jing Zhang ◽

Xiao Zhang ◽

Qing-Ping Wu ◽

Chun-Hui Yan

Keyword(s):

Photoelectron Spectroscopy ◽

Metallic Copper ◽

Metal Organic Frameworks ◽

Aqueous Media ◽

Oxidative Degradation ◽

Acid Orange 7 ◽

X Ray Diffraction ◽

X Ray ◽

Initial Ph ◽

Metal Organic

Calcined Cu-based metal–organic frameworks impregnated with nickel nitrate catalysts (CuNi@C) were synthesised. X-Ray diffraction, scanning electronic microscopy, energy dispersive X-ray spectrometry, and X-ray photoelectron spectroscopy techniques were applied for the characterisation of the synthesised catalyst, which revealed an octahedral particle shape, rough surface, and metallic copper (Cu, CuO) and nickel (Ni, NiO) particles. CuNi@C was fabricated as a novel peroxymonosulfate (PMS) activator for the oxidative degradation of Acid Orange 7 (AO7) in aqueous media. Results showed that the CuNi@C/PMS system can efficiently degrade nearly 100 % of 0.02 mmol L−1 AO7 within 60 min. In addition, the trapping experiments confirmed the participation of sulfate radicals (SO4•−) and hydroxyl radicals (HO•) as reactive species in the system. Furthermore, the effects of parameters including catalyst and PMS dosages, initial concentration of AO7, and pH were studied. Results showed that the decolourisation efficiency increased with the increase of catalyst dosage, but decreased with the increase of AO7 concentration. The optimal PMS concentration was 0.675 mmol L−1, and initial pH showed no significant effect on the degradation of AO7. Moreover, the CuNi@C could be reused four times with good activity and reusability. Findings revealed that the CuNi@C/PMS system shows potential for degrading contaminants in the environment, due to its catalytic activity and non-negligible adsorption.

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Operando high-pressure investigation of size-controlled CuZn catalysts for the methanol synthesis reaction

Nature Communications ◽

10.1038/s41467-021-21604-7 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Núria J. Divins ◽

David Kordus ◽

Janis Timoshenko ◽

Ilya Sinev ◽

Ioannis Zegkinoglou ◽

...

Keyword(s):

High Pressure ◽

Photoelectron Spectroscopy ◽

Active Sites ◽

Surface Segregation ◽

Ambient Pressure ◽

Catalytic Performance ◽

Oxide Interface ◽

X Ray ◽

Oxide Support ◽

Open Questions

AbstractAlthough Cu/ZnO-based catalysts have been long used for the hydrogenation of CO2 to methanol, open questions still remain regarding the role and the dynamic nature of the active sites formed at the metal-oxide interface. Here, we apply high-pressure operando spectroscopy methods to well-defined Cu and Cu0.7Zn0.3 nanoparticles supported on ZnO/Al2O3, γ-Al2O3 and SiO2 to correlate their structure, composition and catalytic performance. We obtain similar activity and methanol selectivity for Cu/ZnO/Al2O3 and CuZn/SiO2, but the methanol yield decreases with time on stream for the latter sample. Operando X-ray absorption spectroscopy data reveal the formation of reduced Zn species coexisting with ZnO on CuZn/SiO2. Near-ambient pressure X-ray photoelectron spectroscopy shows Zn surface segregation and the formation of a ZnO-rich shell on CuZn/SiO2. In this work we demonstrate the beneficial effect of Zn, even in diluted form, and highlight the influence of the oxide support and the Cu-Zn interface in the reactivity.

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Mechanochemical Synthesis of Nickel-Modified Metal–Organic Frameworks for Reduction Reactions

Catalysts ◽

10.3390/catal11050526 ◽

2021 ◽

Vol 11 (5) ◽

pp. 526

Author(s):

Paulette Gómez-López ◽

Martyna Murat ◽

José M. Hidalgo-Herrador ◽

Carolina Carrillo-Carrión ◽

Alina M. Balu ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Metal Organic Framework ◽

Catalytic Performance ◽

Hydrogenation Reaction ◽

Nickel Oxide Nanoparticles ◽

The Sustainable Development ◽

X Ray ◽

Metal Organic ◽

Complementary Techniques ◽

Ni Species

In this work, we report the incorporation of nickel oxide nanoparticles into a metal–organic framework (MOF) structure by a solvent-free mechanochemical strategy. In particular, the zirconium-based MOF UiO-66 was modified with different Ni loadings and characterized using complementary techniques including X-ray diffraction (XRD), N2 porosimetry and X-ray photoelectron spectroscopy (XPS). The catalytic potential of the as-prepared Ni/UiO-66 materials in the hydrogenation reaction of methyl levulinate using 2-propanol as hydrogen donor solvent has been investigated under flow conditions. Under optimized conditions, the 5%Ni/UiO-66 led to the best catalytic performance (70% yield, 100% selectivity to gamma-valerolactone), which could be attributed to the higher content of the Ni species within the MOF structure. The obtained results are promising and contribute to highlighting the great potential of MOFs in biomass upgrading processes, opening the path to the sustainable development of the chemical industry.

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