Francis Verpoort - Academia.edu (original) (raw)

Papers by Francis Verpoort

Journal of Alloys and Compounds, Oct 1, 2023

Journal of CO2 utilization, Jul 1, 2017

A newly Zn-doped ZIF-67 has been synthesized in water at room temperature for the first time with... more A newly Zn-doped ZIF-67 has been synthesized in water at room temperature for the first time without the aid of any organic solvent. The textural and physical properties of the material were analyzed by X-ray diffraction (XRD), thermogravimetric analysis (TGA), N 2 adsorption-desorption, scanning electron microscopy (SEM) and ICP-AES. The catalyst showed quantitative conversions and selectivity for the synthesis of cyclic carbonates starting from epoxides and carbon dioxide. Compared with different reported MOFs as heterogeneous catalysts used for the cycloaddition of carbon dioxide to epoxides, this catalyst outperforms all the reported ones till now. The coupling reaction was studied at different pressures and temperatures applying different epoxide substrates. Additionally, no co-catalyst and solvent were required to obtain excellent conversions. The heterogeneous nature of the catalyst was maintained at least up to four catalytic cycles with a slight loss of activity.

MXene quantum dots (MQDs) sensor is a promising platform for identifying target analytes by sensi... more MXene quantum dots (MQDs) sensor is a promising platform for identifying target analytes by sensing fluorescence, electrochemical signals, photoluminescence, biomedical, and so on. On the way to designing MQDs in the sensors, substantial progress has been made with basic scientific and technological hurdles remaining. Combining specific functional designs of MQDs with mechanistic understanding provides new research prospects and technology opportunities even at the industrial level. However, MQDs must be able to detect target analytes with higher sensitivity, robust stability, and applied compatibility. Here, we review the recent advances and challenges in the synthetic strategies and rational design of MQDs. By zooming in on several representative examples, we discuss the existing potentials of MQDs in the application of fluorescence, electrochemical luminescence, photoluminescence, colorimetric/fluorescent dual‐mode, and biomedical sensors. Finally, we identify the opportunities and challenges to further understanding of MQDs sensors.

Journal of Catalysis, May 1, 2020

Selective hydrogenation of organic functionalities at environmentally benign conditions using vis... more Selective hydrogenation of organic functionalities at environmentally benign conditions using visible light is of great industrial and economic significance. Herein we report visible-light-induced rapid, almost quantitative and selective hydrogenation of olefins to respective mono-reduced products using cooperative performance of Pd(0) nanoparticles (NPs) and Pd(II) ions evenly distributed on a newly synthesized conjugated mesoporous poly-azobenzene network. Role of variable Pd(0)/Pd(II) ratio on the properties of polymeric networks and their overall catalytic abilities is critically investigated. This is the first proposed example of cooperative hydrogenation by simultaneous activation of H 2 and unsaturated substrates using Mott-Schottky heterojunction between Pd NPs and the semiconducting polymer, with the help of Pd(II)site-mediated g-coordination. A control over selective mono-reduction of diene with identical double bonds was also obtained. The catalytic activity retained for other non-olefinic functionalities as well.

Catalysts, Apr 11, 2022

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Chemical Engineering Journal, Mar 1, 2022

Visible light mediated heterogeneous photocatalysis of the fungicide thiabendazole (TBZ; initial ... more Visible light mediated heterogeneous photocatalysis of the fungicide thiabendazole (TBZ; initial concentration of 50 μmol/L) has been investigated using amorphous porous organic polymers (POPs). For the first time, both reversible adsorption in the dark and photocatalytic degradation under light irradiation are simultaneously monitored and kinetically modeled via coupled continuity equations for TBZ in both liquid phase and on the catalyst surface during a sequence of dark/light periods. The final model takes into account the effect of light intensity (28-120 W/m 2) and pH (3-9) on the adsorption and photocatalytic degradation processes. It is found that light intensity maintains a linear relation with both the degradation rate in the solution and on the catalyst surface, while it does not significantly affect the adsorption/desorption rates. The effect of pH was investigated in relation to the speciation of TBZ and its impact on adsorption/desorption and degradation coefficients. It is shown that the different TBZ species have distinct adsorption and desorption coefficients with their charge conditions. Furthermore, changes in pH have a significant effect on the overall removal by adsorption (highest at pH 6.8) or actual degradation (highest at pH 4.4). The proposed model was satisfactory to describe the experimental data with a root-mean-square deviation (RMSD) of 1.88 μmol/L, corresponding to deviations below 4%. In addition, photocatalytic experiments under natural sunlight with a variable visible light intensity of 10 to 125 W/m 2 and reusability of the photocatalyst was successfully validated by the proposed model. Furthermore, the calculated quantum yield for the used POP mounts up to 2.8×10-6 molecules/photon with the space time yield reaches 1.5×10-6 molecules/(photon mg cat), which is an order of magnitude higher than earlier reported values.

Journal of Molecular Liquids, Oct 1, 2021

The development of techniques related to biomass conversion into chemical products needs addition... more The development of techniques related to biomass conversion into chemical products needs additional study and advances. It is necessary to perform experimental investigations and modeling in order to produce information about mixtures that could be used as reaction media or in separation processes. Research on phase equilibrium is fundamental for the achievement of valuable knowledge. Therefore, this research aims to perform a study of xylitol and sorbitol solubility in methanol-ethanol mixtures throughout the molar composition range and at temperatures ranging from 293.15 K to 323.15 K, under atmospheric conditions. The Jouyban-Acree, NRTL and UNIQUAC models were fitted to experimental data. The parameters of the models were explicitly obtained as temperature dependents.

Nanoscale Research Letters, Feb 17, 2020

Nanoscale Au-ZnO heterostructures were fabricated on 4-in. SiO 2 /Si wafers by the atomic layer d... more Nanoscale Au-ZnO heterostructures were fabricated on 4-in. SiO 2 /Si wafers by the atomic layer deposition (ALD) technique. Developed Au-ZnO heterostructures after post-deposition annealing at 250°C were tested for amperometric hydrogen peroxide (H 2 O 2) detection. The surface morphology and nanostructure of Au-ZnO heterostructures were examined by field emission scanning electron microscopy (FE-SEM), Raman spectroscopy, atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), etc. Additionally, the electrochemical behavior of Au-ZnO heterostructures towards H 2 O 2 sensing under various conditions is assessed by chronoamperometry and electrochemical impedance spectroscopy (EIS). The results showed that ALD-fabricated Au-ZnO heterostructures exhibited one of the highest sensitivities of 0.53 μA μM −1 cm −2 , the widest linear H 2 O 2 detection range of 1.0 μM-120 mM, a low limit of detection (LOD) of 0.78 μM, excellent selectivity under the normal operation conditions, and great long-term stability. Utilization of the ALD deposition method opens up a unique opportunity for the improvement of the various capabilities of the devices based on Au-ZnO heterostructures for amperometric detection of different chemicals.

Research Square (Research Square), Dec 16, 2021

Herein, a facile and low-cost route was used to prepare Polydopamine@Zeolitic Imidazolate Framewo... more Herein, a facile and low-cost route was used to prepare Polydopamine@Zeolitic Imidazolate Framework-67 (PDA@ZIF-67). The structure, morphology, surface functional groups and particle size distribution of PDA@ZIF-67 were studied using FTIR, FESEM, EDS, and BET analyses. The specific surface area and diameter of PDA@ZIF-67 were equal to be 78.203 m 2 /g and 4.179 mm, respectively. The PDA@ZIF-67 was used as an adsorbent for the adsorption of methylene blue dye. The results show that the maximum adsorption efficiency of methylene blue on the surface of PDA@ZIF-67 is achieved at pH 2, the temperature of 65°C, 10 mg of adsorbent, and methylene blue concentration of 7.5 ppm. Moreover, the adsorption process's isothermal, thermodynamic, and kinetics were studied entirely to consider the adsorption mechanism. The methylene blue molecules located in the fine pores of the PDA@ZIF-67 adsorbent determine the adsorption rate. Moreover, the adsorption process of methylene blue at high temperatures is a spontaneous and endothermic reaction. The adsorption efficiency of PDA@ZIF-67, after the recovery, reached 62.21%, which is an excellent advantage for using this adsorbent.

Catalysts

The degradation of dyes is a difficult task due to their persistent and stable nature; therefore,... more The degradation of dyes is a difficult task due to their persistent and stable nature; therefore, developing materials with desirable properties to degrade dyes is an important area of research. In the present study, we propose a simple, one-pot mechanochemical approach to synthesize CuO nanoparticles (NPs) using the leaf extract of Seriphidium oliverianum, as a reducing and stabilizing agent. The CuO NPs were characterized via X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL) and Fourier-transform infrared spectroscopy (FTIR). The photocatalytic activity of CuO NPs was monitored using ultraviolet-visible (UV-Vis) spectroscopy. The CuO NPs exhibited high potential for the degradation of water-soluble industrial dyes. The degradation rates for methyl green (MG) and methyl orange (MO) were 65.231% ± 0.242 and 65.078% ± 0.392, respectively. Bio-mechanochemically synthesized CuO NPs proved to be good candidates for efficiently removing dyes from water.

Chemistry Africa

Hexavalent chromium comes into the environment from natural sources and due to anthropogenic [1] ... more Hexavalent chromium comes into the environment from natural sources and due to anthropogenic [1] activity. Mixed oxide chromite, a normal spinel is the main source of chromium in ultramafic and serpentinite rocks. In 2007, Fendorf et.al experimentally verified the genesis of hexavalent chromium from natural sources in soil and ground water [2]. Ground and surface water hexavalent chromium contamination coming from natural sources has been reported from many parts of the globe [3]. Chromium is used extensively in various small-and largescale industries [1]. Chromium and its compounds are extensively used in industry, with the most common and important sources coming from the electroplating, catalyst sector, tanning, water cooling, pulp production, dyes and pigments, film and photography, wood preservation, and alloy manufacture industries. Petroleum refining processes and chromite ore processing have introduced chromium into the soil, air, and water. Chrome plating baths are of two types: hexavalent and trivalent baths. Hexavalent chromium baths are of frequent use. Typical hexavalent chromium bath composition is as follows: (a) electrolytic solution: chromic acid (b) anode: lead with tin up to 7%; (c) operating temperature: 45-60 °C, (d) plating current: 1.5-3.0 kA/m 2. About 35% of used chromium is discharged in the effluent as trivalent and hexavalent chromium. Chromates of barium, lead, and zinc provides the pigments of lemon chromium, chromium yellow, chromium red, chromium orange, zinc yellow, and zinc green glass. Chromium compounds have been used in the formulation of wood preservatives for more than a century. These are ''Wolman compounds'' (based on sodium fluoride and nitrophenol with sodium dichromate or potassium dichromate),

Resources Chemicals and Materials

Two ligands, 1, 3-bis(4-carboxyphenyl)imidazolium chloride and 4, 4՛-bipyridine, were employed to... more Two ligands, 1, 3-bis(4-carboxyphenyl)imidazolium chloride and 4, 4՛-bipyridine, were employed to prepare nickel and zinc azolium based MOFs, 1 and 2 by the mixed ligand solvothermal approach. The positively charged azolium moieties in the imidazolium linker resulted in a charged environment in the as-synthesized frameworks. As a result, 1 and 2 demonstrated preferential adsorption of CO2 over methane molecules in the gas phase adsorption due to the higher quadruple moment of CO2, which interacts more with the positively charged frameworks. Besides, in aqueous media, 1 and 2 exhibited incredible adsorption efficiency for anionic dyes. In the following, MOF 1 was metallated at the carbene site of the azolium linker to generate the novel heterogeneous catalyst 1-Pd, which was successfully applied for Sonogashira and Suzuki-Miyaura coupling reactions without losing its activity after three cycles.

Membranes, 2022

The performance of most polymer membranes suffers from the trade-off relationship between permeab... more The performance of most polymer membranes suffers from the trade-off relationship between permeability and selectivity [...]

Catalysts, 2022

As a well-known greenhouse gas, carbon dioxide (CO2) has attracted increasing levels of attention... more As a well-known greenhouse gas, carbon dioxide (CO2) has attracted increasing levels of attention in areas of energy, environment, climate, etc. Notably, CO2 is an abundant, nonflammable, and renewable C1 feedstock in view of chemistry. Therefore, the transformation of CO2 into organic compounds is an extremely attractive research topic in modern green and sustainable chemistry. Among the numerous CO2 utilization methods, carboxylative cycloaddition of CO2 into propargylic alcohols is an ideal route due to the corresponding products, α-alkylidene cyclic carbonates, which are a series of highly functionalized compounds that supply numerous potential methods for the construction of various synthetically and biologically valuable agents. This cyclization reaction has been intensively studied and systematically summarized, in the past years. Therefore, attention has been gradually transferred to produce more derivative compounds. Herein, the tandem reactions of this cyclization with hyd...

Journal of Alloys and Compounds, Oct 1, 2023

Journal of CO2 utilization, Jul 1, 2017

A newly Zn-doped ZIF-67 has been synthesized in water at room temperature for the first time with... more A newly Zn-doped ZIF-67 has been synthesized in water at room temperature for the first time without the aid of any organic solvent. The textural and physical properties of the material were analyzed by X-ray diffraction (XRD), thermogravimetric analysis (TGA), N 2 adsorption-desorption, scanning electron microscopy (SEM) and ICP-AES. The catalyst showed quantitative conversions and selectivity for the synthesis of cyclic carbonates starting from epoxides and carbon dioxide. Compared with different reported MOFs as heterogeneous catalysts used for the cycloaddition of carbon dioxide to epoxides, this catalyst outperforms all the reported ones till now. The coupling reaction was studied at different pressures and temperatures applying different epoxide substrates. Additionally, no co-catalyst and solvent were required to obtain excellent conversions. The heterogeneous nature of the catalyst was maintained at least up to four catalytic cycles with a slight loss of activity.

MXene quantum dots (MQDs) sensor is a promising platform for identifying target analytes by sensi... more MXene quantum dots (MQDs) sensor is a promising platform for identifying target analytes by sensing fluorescence, electrochemical signals, photoluminescence, biomedical, and so on. On the way to designing MQDs in the sensors, substantial progress has been made with basic scientific and technological hurdles remaining. Combining specific functional designs of MQDs with mechanistic understanding provides new research prospects and technology opportunities even at the industrial level. However, MQDs must be able to detect target analytes with higher sensitivity, robust stability, and applied compatibility. Here, we review the recent advances and challenges in the synthetic strategies and rational design of MQDs. By zooming in on several representative examples, we discuss the existing potentials of MQDs in the application of fluorescence, electrochemical luminescence, photoluminescence, colorimetric/fluorescent dual‐mode, and biomedical sensors. Finally, we identify the opportunities and challenges to further understanding of MQDs sensors.

Journal of Catalysis, May 1, 2020

Selective hydrogenation of organic functionalities at environmentally benign conditions using vis... more Selective hydrogenation of organic functionalities at environmentally benign conditions using visible light is of great industrial and economic significance. Herein we report visible-light-induced rapid, almost quantitative and selective hydrogenation of olefins to respective mono-reduced products using cooperative performance of Pd(0) nanoparticles (NPs) and Pd(II) ions evenly distributed on a newly synthesized conjugated mesoporous poly-azobenzene network. Role of variable Pd(0)/Pd(II) ratio on the properties of polymeric networks and their overall catalytic abilities is critically investigated. This is the first proposed example of cooperative hydrogenation by simultaneous activation of H 2 and unsaturated substrates using Mott-Schottky heterojunction between Pd NPs and the semiconducting polymer, with the help of Pd(II)site-mediated g-coordination. A control over selective mono-reduction of diene with identical double bonds was also obtained. The catalytic activity retained for other non-olefinic functionalities as well.

Catalysts, Apr 11, 2022

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Chemical Engineering Journal, Mar 1, 2022

Visible light mediated heterogeneous photocatalysis of the fungicide thiabendazole (TBZ; initial ... more Visible light mediated heterogeneous photocatalysis of the fungicide thiabendazole (TBZ; initial concentration of 50 μmol/L) has been investigated using amorphous porous organic polymers (POPs). For the first time, both reversible adsorption in the dark and photocatalytic degradation under light irradiation are simultaneously monitored and kinetically modeled via coupled continuity equations for TBZ in both liquid phase and on the catalyst surface during a sequence of dark/light periods. The final model takes into account the effect of light intensity (28-120 W/m 2) and pH (3-9) on the adsorption and photocatalytic degradation processes. It is found that light intensity maintains a linear relation with both the degradation rate in the solution and on the catalyst surface, while it does not significantly affect the adsorption/desorption rates. The effect of pH was investigated in relation to the speciation of TBZ and its impact on adsorption/desorption and degradation coefficients. It is shown that the different TBZ species have distinct adsorption and desorption coefficients with their charge conditions. Furthermore, changes in pH have a significant effect on the overall removal by adsorption (highest at pH 6.8) or actual degradation (highest at pH 4.4). The proposed model was satisfactory to describe the experimental data with a root-mean-square deviation (RMSD) of 1.88 μmol/L, corresponding to deviations below 4%. In addition, photocatalytic experiments under natural sunlight with a variable visible light intensity of 10 to 125 W/m 2 and reusability of the photocatalyst was successfully validated by the proposed model. Furthermore, the calculated quantum yield for the used POP mounts up to 2.8×10-6 molecules/photon with the space time yield reaches 1.5×10-6 molecules/(photon mg cat), which is an order of magnitude higher than earlier reported values.

Journal of Molecular Liquids, Oct 1, 2021

The development of techniques related to biomass conversion into chemical products needs addition... more The development of techniques related to biomass conversion into chemical products needs additional study and advances. It is necessary to perform experimental investigations and modeling in order to produce information about mixtures that could be used as reaction media or in separation processes. Research on phase equilibrium is fundamental for the achievement of valuable knowledge. Therefore, this research aims to perform a study of xylitol and sorbitol solubility in methanol-ethanol mixtures throughout the molar composition range and at temperatures ranging from 293.15 K to 323.15 K, under atmospheric conditions. The Jouyban-Acree, NRTL and UNIQUAC models were fitted to experimental data. The parameters of the models were explicitly obtained as temperature dependents.

Nanoscale Research Letters, Feb 17, 2020

Nanoscale Au-ZnO heterostructures were fabricated on 4-in. SiO 2 /Si wafers by the atomic layer d... more Nanoscale Au-ZnO heterostructures were fabricated on 4-in. SiO 2 /Si wafers by the atomic layer deposition (ALD) technique. Developed Au-ZnO heterostructures after post-deposition annealing at 250°C were tested for amperometric hydrogen peroxide (H 2 O 2) detection. The surface morphology and nanostructure of Au-ZnO heterostructures were examined by field emission scanning electron microscopy (FE-SEM), Raman spectroscopy, atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), etc. Additionally, the electrochemical behavior of Au-ZnO heterostructures towards H 2 O 2 sensing under various conditions is assessed by chronoamperometry and electrochemical impedance spectroscopy (EIS). The results showed that ALD-fabricated Au-ZnO heterostructures exhibited one of the highest sensitivities of 0.53 μA μM −1 cm −2 , the widest linear H 2 O 2 detection range of 1.0 μM-120 mM, a low limit of detection (LOD) of 0.78 μM, excellent selectivity under the normal operation conditions, and great long-term stability. Utilization of the ALD deposition method opens up a unique opportunity for the improvement of the various capabilities of the devices based on Au-ZnO heterostructures for amperometric detection of different chemicals.

Research Square (Research Square), Dec 16, 2021

Herein, a facile and low-cost route was used to prepare Polydopamine@Zeolitic Imidazolate Framewo... more Herein, a facile and low-cost route was used to prepare Polydopamine@Zeolitic Imidazolate Framework-67 (PDA@ZIF-67). The structure, morphology, surface functional groups and particle size distribution of PDA@ZIF-67 were studied using FTIR, FESEM, EDS, and BET analyses. The specific surface area and diameter of PDA@ZIF-67 were equal to be 78.203 m 2 /g and 4.179 mm, respectively. The PDA@ZIF-67 was used as an adsorbent for the adsorption of methylene blue dye. The results show that the maximum adsorption efficiency of methylene blue on the surface of PDA@ZIF-67 is achieved at pH 2, the temperature of 65°C, 10 mg of adsorbent, and methylene blue concentration of 7.5 ppm. Moreover, the adsorption process's isothermal, thermodynamic, and kinetics were studied entirely to consider the adsorption mechanism. The methylene blue molecules located in the fine pores of the PDA@ZIF-67 adsorbent determine the adsorption rate. Moreover, the adsorption process of methylene blue at high temperatures is a spontaneous and endothermic reaction. The adsorption efficiency of PDA@ZIF-67, after the recovery, reached 62.21%, which is an excellent advantage for using this adsorbent.

Catalysts

The degradation of dyes is a difficult task due to their persistent and stable nature; therefore,... more The degradation of dyes is a difficult task due to their persistent and stable nature; therefore, developing materials with desirable properties to degrade dyes is an important area of research. In the present study, we propose a simple, one-pot mechanochemical approach to synthesize CuO nanoparticles (NPs) using the leaf extract of Seriphidium oliverianum, as a reducing and stabilizing agent. The CuO NPs were characterized via X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL) and Fourier-transform infrared spectroscopy (FTIR). The photocatalytic activity of CuO NPs was monitored using ultraviolet-visible (UV-Vis) spectroscopy. The CuO NPs exhibited high potential for the degradation of water-soluble industrial dyes. The degradation rates for methyl green (MG) and methyl orange (MO) were 65.231% ± 0.242 and 65.078% ± 0.392, respectively. Bio-mechanochemically synthesized CuO NPs proved to be good candidates for efficiently removing dyes from water.

Chemistry Africa

Hexavalent chromium comes into the environment from natural sources and due to anthropogenic [1] ... more Hexavalent chromium comes into the environment from natural sources and due to anthropogenic [1] activity. Mixed oxide chromite, a normal spinel is the main source of chromium in ultramafic and serpentinite rocks. In 2007, Fendorf et.al experimentally verified the genesis of hexavalent chromium from natural sources in soil and ground water [2]. Ground and surface water hexavalent chromium contamination coming from natural sources has been reported from many parts of the globe [3]. Chromium is used extensively in various small-and largescale industries [1]. Chromium and its compounds are extensively used in industry, with the most common and important sources coming from the electroplating, catalyst sector, tanning, water cooling, pulp production, dyes and pigments, film and photography, wood preservation, and alloy manufacture industries. Petroleum refining processes and chromite ore processing have introduced chromium into the soil, air, and water. Chrome plating baths are of two types: hexavalent and trivalent baths. Hexavalent chromium baths are of frequent use. Typical hexavalent chromium bath composition is as follows: (a) electrolytic solution: chromic acid (b) anode: lead with tin up to 7%; (c) operating temperature: 45-60 °C, (d) plating current: 1.5-3.0 kA/m 2. About 35% of used chromium is discharged in the effluent as trivalent and hexavalent chromium. Chromates of barium, lead, and zinc provides the pigments of lemon chromium, chromium yellow, chromium red, chromium orange, zinc yellow, and zinc green glass. Chromium compounds have been used in the formulation of wood preservatives for more than a century. These are ''Wolman compounds'' (based on sodium fluoride and nitrophenol with sodium dichromate or potassium dichromate),

Resources Chemicals and Materials

Two ligands, 1, 3-bis(4-carboxyphenyl)imidazolium chloride and 4, 4՛-bipyridine, were employed to... more Two ligands, 1, 3-bis(4-carboxyphenyl)imidazolium chloride and 4, 4՛-bipyridine, were employed to prepare nickel and zinc azolium based MOFs, 1 and 2 by the mixed ligand solvothermal approach. The positively charged azolium moieties in the imidazolium linker resulted in a charged environment in the as-synthesized frameworks. As a result, 1 and 2 demonstrated preferential adsorption of CO2 over methane molecules in the gas phase adsorption due to the higher quadruple moment of CO2, which interacts more with the positively charged frameworks. Besides, in aqueous media, 1 and 2 exhibited incredible adsorption efficiency for anionic dyes. In the following, MOF 1 was metallated at the carbene site of the azolium linker to generate the novel heterogeneous catalyst 1-Pd, which was successfully applied for Sonogashira and Suzuki-Miyaura coupling reactions without losing its activity after three cycles.

Membranes, 2022

The performance of most polymer membranes suffers from the trade-off relationship between permeab... more The performance of most polymer membranes suffers from the trade-off relationship between permeability and selectivity [...]

Catalysts, 2022

As a well-known greenhouse gas, carbon dioxide (CO2) has attracted increasing levels of attention... more As a well-known greenhouse gas, carbon dioxide (CO2) has attracted increasing levels of attention in areas of energy, environment, climate, etc. Notably, CO2 is an abundant, nonflammable, and renewable C1 feedstock in view of chemistry. Therefore, the transformation of CO2 into organic compounds is an extremely attractive research topic in modern green and sustainable chemistry. Among the numerous CO2 utilization methods, carboxylative cycloaddition of CO2 into propargylic alcohols is an ideal route due to the corresponding products, α-alkylidene cyclic carbonates, which are a series of highly functionalized compounds that supply numerous potential methods for the construction of various synthetically and biologically valuable agents. This cyclization reaction has been intensively studied and systematically summarized, in the past years. Therefore, attention has been gradually transferred to produce more derivative compounds. Herein, the tandem reactions of this cyclization with hyd...

IntechOpen, 2018

In recent years, the olefins metathesis has established itself as a powerful tool for carbon-carb... more In recent years, the olefins metathesis has established itself as a powerful tool for carbon-carbon bonds forming and has found numerous applications in polymer chemistry. One of the important directions of metathesis is the polymerization with cycle opening. A study of new ruthenium catalysts, resistant to the many functional groups effects, has showed the possibility of synthesizing functionalized polymers with unique properties. In this chapter, reactivity and activation parameters of eight different norbornene dicar-boxylic acid alkyl esters in the presence of a Hoveyda-Grubbs II catalyst for the ring opening metathesis polymerization were determined by 1 H NMR analysis in-situ. The molecules of esters differ in the aliphatic radical structure and the location of the sub-stituent groups. Kinetic studies have shown that effective polymerization constants and activation parameters strongly depend on the monomer structure. It is shown that the elongation of the aliphatic radical does not significantly affect the reactivity, but significantly changes the activation parameters. The branching of the aliphatic radical significantly affects both the reactivity of the corresponding ester and the activation parameters of the polymerization. The position of the substituents in the norbornene ring of the ester also has a significant effect on the activation parameters of metathesis polymerization.