Pub Date : 2025-10-25DOI: 10.1016/j.micromeso.2025.113907
Rui Geng, Xianjun Niu, Yajie Liu
HZSM-5 zeolite is extensively used in methanol-to-aromatics (MTA) reactions; however, its low aromatics selectivity limits its performance due to weak intrinsic aromatization ability. In this study, a series of bifunctional x-Ga2O3/HZSM-5 were synthesized by mechanically mixing different Ga2O3 isomers with HZSM-5 to systematically investigate the influence of the crystal structure on methanol aromatization. Among them, β-Ga2O3/HZSM-5 catalyst exhibited the highest aromatic selectivity, reaching 40 mol%. Structural characterization by XRD, N2 adsorption, XPS, H2-TPR, XANES, and EXAFS analyses revealed that the dispersion and reducibility of extra-framework Ga3+ species varied with the Ga2O3 structure. In particular, the monoclinic β-Ga2O3 exhibited a pronounced interaction with Brønsted acid sites of HZSM-5, promoting the formation of highly active and stable four-coordinated [Ga2O2]2+ dimers. These species functioned as efficient dehydrogenation and cyclization centers, thereby markedly promoting aromatics production.
{"title":"Effect of extra-framework Ga2O3 species in Ga/ZSM-5 catalysts on methanol-to-aromatics reaction","authors":"Rui Geng, Xianjun Niu, Yajie Liu","doi":"10.1016/j.micromeso.2025.113907","DOIUrl":"10.1016/j.micromeso.2025.113907","url":null,"abstract":"<div><div>HZSM-5 zeolite is extensively used in methanol-to-aromatics (MTA) reactions; however, its low aromatics selectivity limits its performance due to weak intrinsic aromatization ability. In this study, a series of bifunctional <em>x</em>-Ga<sub>2</sub>O<sub>3</sub>/HZSM-5 were synthesized by mechanically mixing different Ga<sub>2</sub>O<sub>3</sub> isomers with HZSM-5 to systematically investigate the influence of the crystal structure on methanol aromatization. Among them, β-Ga<sub>2</sub>O<sub>3</sub>/HZSM-5 catalyst exhibited the highest aromatic selectivity, reaching 40 mol%. Structural characterization by XRD, N<sub>2</sub> adsorption, XPS, H<sub>2</sub>-TPR, XANES, and EXAFS analyses revealed that the dispersion and reducibility of extra-framework Ga<sup>3+</sup> species varied with the Ga<sub>2</sub>O<sub>3</sub> structure. In particular, the monoclinic β-Ga<sub>2</sub>O<sub>3</sub> exhibited a pronounced interaction with Brønsted acid sites of HZSM-5, promoting the formation of highly active and stable four-coordinated [Ga<sub>2</sub>O<sub>2</sub>]<sup>2+</sup> dimers. These species functioned as efficient dehydrogenation and cyclization centers, thereby markedly promoting aromatics production.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"400 ","pages":"Article 113907"},"PeriodicalIF":4.7,"publicationDate":"2025-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145425236","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-25DOI: 10.1016/j.micromeso.2025.113903
Zhiping Wang , Rui Zhu , Jiejie Ling , Han Jiang , Lei Liu , Yan Gao , Hailang Liu , Le Xu
Zeolite Beta, discovered in 1967, features a unique three-dimensional (3D) 12-ring channel system and a highly tunable Si/Al ratio (SAR), granting exceptional stability and acidity crucial for catalysis. While conventional hydrothermal synthesis normally yields zeolite Beta with the SAR range of 10–30 using tetraethylammonium hydroxide (TEAOH) as the organic structure-directing agent (OSDA), the discovery of Al-rich natural mineral (Tschernichite) with the ∗BEA topology (SAR∼3.3) spurred efforts to synthesize low-SAR Beta zeolite for enhanced acid site density, hydrophilicity and ion-exchange capacity, enabling applications like dehydration, separation and shape-selective catalysis. However, achieving low SARs for the hydrothermal crystallization of zeolite Beta is still challenging, requiring excess Na+ which promotes impurity phases (e.g., GIS, ANA, MOR), prolongs crystallization period and reduces yield. Inspired by our recent work on the kinetic-control synthesis of high-silica NaY zeolite using aluminophosphate as the aluminum carrier, this study presents an accelerated, impurity-free synthetic route to achieve Al-rich zeolite Beta. Using the pre-synthesized aluminophosphate (e.g., AlPO-5) as a partial Al source favors the formation of a silica-rich Beta zeolite nucleus, thus effectively suppresses impurities (eliminating GIS phase in Na+-containing system) and amorphous phase (in Na+-free system), ultimately accelerating crystallization process. Based on this synthetic control, this study successfully synthesized the phase-pure Beta zeolite at SAR of 7.55 (Na+-free) and 6.58 (Na+-containing), while this strategy was extended to the Beta zeolite synthesis with other aluminophosphate, including SSZ-51 (SFO) and AlPO-18 (AEI).
{"title":"Accelerated, impurity-free crystallization of aluminum-rich beta zeolite with aluminophosphate as the aluminum carrier","authors":"Zhiping Wang , Rui Zhu , Jiejie Ling , Han Jiang , Lei Liu , Yan Gao , Hailang Liu , Le Xu","doi":"10.1016/j.micromeso.2025.113903","DOIUrl":"10.1016/j.micromeso.2025.113903","url":null,"abstract":"<div><div>Zeolite Beta, discovered in 1967, features a unique three-dimensional (3D) 12-ring channel system and a highly tunable Si/Al ratio (SAR), granting exceptional stability and acidity crucial for catalysis. While conventional hydrothermal synthesis normally yields zeolite Beta with the SAR range of 10–30 using tetraethylammonium hydroxide (TEAOH) as the organic structure-directing agent (OSDA), the discovery of Al-rich natural mineral (Tschernichite) with the <strong>∗BEA</strong> topology (SAR∼3.3) spurred efforts to synthesize low-SAR Beta zeolite for enhanced acid site density, hydrophilicity and ion-exchange capacity, enabling applications like dehydration, separation and shape-selective catalysis. However, achieving low SARs for the hydrothermal crystallization of zeolite Beta is still challenging, requiring excess Na<sup>+</sup> which promotes impurity phases (e.g., <strong>GIS</strong>, <strong>ANA</strong>, <strong>MOR</strong>), prolongs crystallization period and reduces yield. Inspired by our recent work on the kinetic-control synthesis of high-silica NaY zeolite using aluminophosphate as the aluminum carrier, this study presents an accelerated, impurity-free synthetic route to achieve Al-rich zeolite Beta. Using the pre-synthesized aluminophosphate (e.g., AlPO-5) as a partial Al source favors the formation of a silica-rich Beta zeolite nucleus, thus effectively suppresses impurities (eliminating <strong>GIS</strong> phase in Na<sup>+</sup>-containing system) and amorphous phase (in Na<sup>+</sup>-free system), ultimately accelerating crystallization process. Based on this synthetic control, this study successfully synthesized the phase-pure Beta zeolite at SAR of 7.55 (Na<sup>+</sup>-free) and 6.58 (Na<sup>+</sup>-containing), while this strategy was extended to the Beta zeolite synthesis with other aluminophosphate, including SSZ-51 (<strong>SFO)</strong> and AlPO-18 (<strong>AEI)</strong>.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"400 ","pages":"Article 113903"},"PeriodicalIF":4.7,"publicationDate":"2025-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145359750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-24DOI: 10.1016/j.micromeso.2025.113906
Bidemi T. Fashina, Anastasia G. Ilgen
The understanding of reactions in nanoscale confinement is important for predicting fate and transport of ions and the development of environmental remediation and resource recovery technologies. Here, we investigated the effect of nanoconfinement on the adsorption kinetics of lutetium (Lu3+), europium (Eu3+), and neodymium (Nd3+) on two cylindrical mesoporous silicas with pore diameters of 4 nm and 7 nm, and one non-porous silica. The three lanthanides differ in their solvated radius, solvation energy, and water exchange rate constants, which enables inquiry into the role of solvation properties on the adsorption kinetics of the three lanthanides. The measured values of the adsorption rate constants (k) and the equilibrium surface coverages (qe) indicate that the uptake of the three lanthanides is faster, and coverage is higher on non-porous silica compared to the porous silicas. We assign this trend to the energy barrier associated with permeation of ions into nanoscale pores and the larger ratio of outer-sphere to inner-sphere complexes that form on the non-porous silica. The k was higher on the 7 nm porous compared 4 nm porous silica suggesting that the energy barrier for ion permeation into smaller pores is higher (less favorable). The qe increased with decreasing pore diameter, which we attribute to the lower desolvation cost in smaller pores thus facilitating more inner-sphere complexation. The solvation energy and solvated radius were the most important solvation properties dictating the adsorption kinetics of the three lanthanides. The reported water exchange rate for the first solvation shell for the three lanthanides did not correlate with the observed adsorption rate constants.
{"title":"Lanthanide adsorption kinetics in silica nanopores","authors":"Bidemi T. Fashina, Anastasia G. Ilgen","doi":"10.1016/j.micromeso.2025.113906","DOIUrl":"10.1016/j.micromeso.2025.113906","url":null,"abstract":"<div><div>The understanding of reactions in nanoscale confinement is important for predicting fate and transport of ions and the development of environmental remediation and resource recovery technologies. Here, we investigated the effect of nanoconfinement on the adsorption kinetics of lutetium (Lu<sup>3+</sup>), europium (Eu<sup>3+</sup>), and neodymium (Nd<sup>3+</sup>) on two cylindrical mesoporous silicas with pore diameters of 4 nm and 7 nm, and one non-porous silica. The three lanthanides differ in their solvated radius, solvation energy, and water exchange rate constants, which enables inquiry into the role of solvation properties on the adsorption kinetics of the three lanthanides. The measured values of the adsorption rate constants (<em>k</em>) and the equilibrium surface coverages (<em>q</em><sub><em>e</em></sub>) indicate that the uptake of the three lanthanides is faster, and coverage is higher on non-porous silica compared to the porous silicas. We assign this trend to the energy barrier associated with permeation of ions into nanoscale pores and the larger ratio of outer-sphere to inner-sphere complexes that form on the non-porous silica. The <em>k</em> was higher on the 7 nm porous compared 4 nm porous silica suggesting that the energy barrier for ion permeation into smaller pores is higher (less favorable). The <em>q</em><sub><em>e</em></sub> increased with decreasing pore diameter, which we attribute to the lower desolvation cost in smaller pores thus facilitating more inner-sphere complexation. The solvation energy and solvated radius were the most important solvation properties dictating the adsorption kinetics of the three lanthanides. The reported water exchange rate for the first solvation shell for the three lanthanides did not correlate with the observed adsorption rate constants.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"400 ","pages":"Article 113906"},"PeriodicalIF":4.7,"publicationDate":"2025-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145425188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-23DOI: 10.1016/j.micromeso.2025.113904
Eduardo Antonio Pinto Dias , Débora Guimarães da Silva , Marcelo da Costa Amaral , Leonardo dos Santos Pereira , Darley Carrijo de Melo , Wander Luiz Vasconcelos
Over the past few years, efforts have been made to find solutions to combat climate change by capturing CO2 from industrial processes and from the atmosphere. Zeolites, a class of microporous materials with crystalline structures that display properties for adsorption, separation, and capture of gases, have been praised for effectively capturing and removing CO2. In this review, the properties of zeolites as CO2 adsorbents are discussed, presenting and addressing their potential and drawbacks. For this purpose, an overview of the types of zeolites (structures, classification and industrial applications) is presented. Then, the adsorption mechanisms, the relationship between the physicochemical properties of zeolites and their performance as CO2 adsorbents are systematically discussed. Based on the trends and properties identified, the state of the art on the synthesis, modification and shaping of zeolites, a fundamental step for their application as industrial adsorbents, is discussed. The application in gas processing is examined, focusing on natural gas processing. Finally, the challenges and the outlook for CO2 adsorption are highlighted. Recent advancements in zeolite development and application have demonstrated remarkable improvements in CO2 adsorption efficiency and versatility, reaffirming their importance in the transition to a low-carbon economy. However, the industrial application of zeolite in CO2 adsorption still presents significant challenges, such as enhancing adsorption and desorption capacity under real conditions, reducing the costs and impacts of synthesis and ensuring that the processes are environmentally viable.
{"title":"CO2 adsorption by zeolites: State-of-Art, techniques and emerging trends","authors":"Eduardo Antonio Pinto Dias , Débora Guimarães da Silva , Marcelo da Costa Amaral , Leonardo dos Santos Pereira , Darley Carrijo de Melo , Wander Luiz Vasconcelos","doi":"10.1016/j.micromeso.2025.113904","DOIUrl":"10.1016/j.micromeso.2025.113904","url":null,"abstract":"<div><div>Over the past few years, efforts have been made to find solutions to combat climate change by capturing CO<sub>2</sub> from industrial processes and from the atmosphere. Zeolites, a class of microporous materials with crystalline structures that display properties for adsorption, separation, and capture of gases, have been praised for effectively capturing and removing CO<sub>2</sub>. In this review, the properties of zeolites as CO<sub>2</sub> adsorbents are discussed, presenting and addressing their potential and drawbacks. For this purpose, an overview of the types of zeolites (structures, classification and industrial applications) is presented. Then, the adsorption mechanisms, the relationship between the physicochemical properties of zeolites and their performance as CO<sub>2</sub> adsorbents are systematically discussed. Based on the trends and properties identified, the state of the art on the synthesis, modification and shaping of zeolites, a fundamental step for their application as industrial adsorbents, is discussed. The application in gas processing is examined, focusing on natural gas processing. Finally, the challenges and the outlook for CO<sub>2</sub> adsorption are highlighted. Recent advancements in zeolite development and application have demonstrated remarkable improvements in CO<sub>2</sub> adsorption efficiency and versatility, reaffirming their importance in the transition to a low-carbon economy. However, the industrial application of zeolite in CO<sub>2</sub> adsorption still presents significant challenges, such as enhancing adsorption and desorption capacity under real conditions, reducing the costs and impacts of synthesis and ensuring that the processes are environmentally viable.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"400 ","pages":"Article 113904"},"PeriodicalIF":4.7,"publicationDate":"2025-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145425189","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-23DOI: 10.1016/j.micromeso.2025.113905
Gavriel Arbiv , Sambhu Radhakrishnan , Alysson F. Morais , C. Vinod Chandran , Dries Vandenabeele , Dirk Dom , Karel Duerinckx , Christine E.A. Kirschhock , Eric Breynaert
Competitive adsorption is a major challenge in understanding catalytic activity, selectivity and reaction mechanisms in confined environments such as zeolites. This study investigated competitive adsorption in MFI-type zeolites (ZSM-5) using solid-state NMR, focusing on the interplay between toluene and water. Quantitative 1H NMR spectroscopy identified three distinct populations of adsorbed toluene evolving with increasing toluene loading. The adsorption behavior was consistent across a series of samples with Si/Al ratio ranging from 11.5 to 140. Combining 1D and 2D NMR techniques with sample engineering, selectively blocking the straight channels of MFI, and thus the access pathway for toluene, with furfuryl alcohol polymers, internal and external toluene populations could be differentiated. Crucially, introducing water to toluene-loaded zeolites caused a partial displacement of toluene from the internal channels, but significant removal from the pore mouths. This displacement occurred even in the highly hydrophobic zeolite (Si/Al = 140), where water still preferentially adsorbed to Brønsted acid sites and silanol species. These findings demonstrate how competitive adsorption of solvents, products, or impurities could influence, or could be exploited to steer, selectivity and efficiency in catalytic transformations in zeolites. Understanding such effects is crucial for the rational optimization of reaction environments in catalytic systems containing water.
{"title":"Competitive adsorption of toluene and water in MFI-type zeolites probed by solid-state NMR spectroscopy","authors":"Gavriel Arbiv , Sambhu Radhakrishnan , Alysson F. Morais , C. Vinod Chandran , Dries Vandenabeele , Dirk Dom , Karel Duerinckx , Christine E.A. Kirschhock , Eric Breynaert","doi":"10.1016/j.micromeso.2025.113905","DOIUrl":"10.1016/j.micromeso.2025.113905","url":null,"abstract":"<div><div>Competitive adsorption is a major challenge in understanding catalytic activity, selectivity and reaction mechanisms in confined environments such as zeolites. This study investigated competitive adsorption in MFI-type zeolites (ZSM-5) using solid-state NMR, focusing on the interplay between toluene and water. Quantitative <sup>1</sup>H NMR spectroscopy identified three distinct populations of adsorbed toluene evolving with increasing toluene loading. The adsorption behavior was consistent across a series of samples with Si/Al ratio ranging from 11.5 to 140. Combining 1D and 2D NMR techniques with sample engineering, selectively blocking the straight channels of MFI, and thus the access pathway for toluene, with furfuryl alcohol polymers, internal and external toluene populations could be differentiated. Crucially, introducing water to toluene-loaded zeolites caused a partial displacement of toluene from the internal channels, but significant removal from the pore mouths. This displacement occurred even in the highly hydrophobic zeolite (Si/Al = 140), where water still preferentially adsorbed to Brønsted acid sites and silanol species. These findings demonstrate how competitive adsorption of solvents, products, or impurities could influence, or could be exploited to steer, selectivity and efficiency in catalytic transformations in zeolites. Understanding such effects is crucial for the rational optimization of reaction environments in catalytic systems containing water.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"400 ","pages":"Article 113905"},"PeriodicalIF":4.7,"publicationDate":"2025-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145425237","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-22DOI: 10.1016/j.micromeso.2025.113898
Taeyi Nam, Shunsaku Yasumura, Masaru Ogura
In this study, we investigate the Cs+ ion-exchange behavior of eight zeolites (K-A, Na-A, Ca-A, Na-X, Na-Y, Na-mordenite, Na-ZSM-5, and Na-SSZ-13) with varying framework structures, SiO2/Al2O3 ratios, and Brønsted acidity. Experimental results demonstrate that Na-type zeolites undergo a 1:1 ion-exchange reaction with Cs+. Additionally, Na-type zeolites exhibited significantly higher Cs+ exchange capacities compared to K-type and Ca-type zeolites. Zeolites containing 8-membered rings (8 MR) and those with high SiO2/Al2O3 ratios showed enhanced Cs + ion-exchange selectivity. Brønsted acidity significantly promoted Cs+ exchange in Na-mordenite and Na-ZSM-5, but had little effect on LTA and FAU. These findings clarify the structural and chemical factors influencing Cs+ ion-exchange and provide valuable insights for designing optimized zeolites for radioactive Cs+ removal.
{"title":"Comparative study on Cs+ ion-exchange behavior in zeolites with different framework structures and compositional characteristics","authors":"Taeyi Nam, Shunsaku Yasumura, Masaru Ogura","doi":"10.1016/j.micromeso.2025.113898","DOIUrl":"10.1016/j.micromeso.2025.113898","url":null,"abstract":"<div><div>In this study, we investigate the Cs<sup>+</sup> ion-exchange behavior of eight zeolites (K-A, Na-A, Ca-A, Na-X, Na-Y, Na-mordenite, Na-ZSM-5, and Na-SSZ-13) with varying framework structures, SiO<sub>2</sub>/Al<sub>2</sub>O<sub>3</sub> ratios, and Brønsted acidity. Experimental results demonstrate that Na-type zeolites undergo a 1:1 ion-exchange reaction with Cs<sup>+</sup>. Additionally, Na-type zeolites exhibited significantly higher Cs<sup>+</sup> exchange capacities compared to K-type and Ca-type zeolites. Zeolites containing 8-membered rings (8 MR) and those with high SiO<sub>2</sub>/Al<sub>2</sub>O<sub>3</sub> ratios showed enhanced Cs <sup>+</sup> ion-exchange selectivity. Brønsted acidity significantly promoted Cs<sup>+</sup> exchange in Na-mordenite and Na-ZSM-5, but had little effect on LTA and FAU. These findings clarify the structural and chemical factors influencing Cs<sup>+</sup> ion-exchange and provide valuable insights for designing optimized zeolites for radioactive Cs<sup>+</sup> removal.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"400 ","pages":"Article 113898"},"PeriodicalIF":4.7,"publicationDate":"2025-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145359751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-21DOI: 10.1016/j.micromeso.2025.113902
K.J.B. Alloko , L. Cantrel , J. Denis , T. Loiseau , X. Deschanels , J. Causse , A. Moissette , C. Volkringer , A. Grégoire
This study investigates the property of Metal-Organic Frameworks (MOFs) grafted with Prussian blue analogs (PBA) for the efficient removal of Cs+ ions from aqueous solutions. MIL-101(Cr)-SO3H-PBA material was synthesized using a two-step process: hydrothermal reaction between monosodium 2-sulfoterephthalic acid (BDC-SO3Na) and chromium oxide (CrO3) to produce MIL-101(Cr)-SO3H, followed by grafting with CuK2[Fe(CN)6] (PBA). Both materials were characterized using XRD, IR, N2 sorption and Raman spectroscopy. The results confirmed the conservation of MOF porosity after functionalization and the successful incorporation of PBA. Batch adsorption experiments were conducted to evaluate Cs + removal performance of the adsorbents. The study examined contact time (up to 1440 min), pH (2, 7 and 11), initial Cs+ concentration (from 9 ppb to 1800 ppm) and competing ions. The resistance of the porous solids under drastic conditions involving gamma radiation (from 0.5 MGy up to10 MGy) was also investigated.
MI-101(Cr)-SO3H-PBA exhibited a maximum Cs + adsorption capacity of 242 mg.gMOF−1, compared to 161 mg.gMOF−1 for pristine MIL-101(Cr)-SO3H and showed high selectivity toward Cs+ in the presence of competing ions (Na+, K+, Mg2+, Ca2+, Sr2+). MI-101(Cr)-SO3H-PBA also demonstrates remarkable stability under radiation and alkaline conditions, maintaining 95 % efficiency, whereas the performance of pristine MIL-101(Cr)-SO3H material decreased significantly (7.5-fold decrease).
{"title":"Prussian blue functionalized MIL-101(Cr)-SO3H for Cs+ ion capture for the management of contaminated water","authors":"K.J.B. Alloko , L. Cantrel , J. Denis , T. Loiseau , X. Deschanels , J. Causse , A. Moissette , C. Volkringer , A. Grégoire","doi":"10.1016/j.micromeso.2025.113902","DOIUrl":"10.1016/j.micromeso.2025.113902","url":null,"abstract":"<div><div>This study investigates the property of Metal-Organic Frameworks (MOFs) grafted with Prussian blue analogs (PBA) for the efficient removal of Cs<sup>+</sup> ions from aqueous solutions. MIL-101(Cr)-SO<sub>3</sub>H-PBA material was synthesized using a two-step process: hydrothermal reaction between monosodium 2-sulfoterephthalic acid (BDC-SO<sub>3</sub>Na) and chromium oxide (CrO<sub>3</sub>) to produce MIL-101(Cr)-SO<sub>3</sub>H, followed by grafting with CuK<sub>2</sub>[Fe(CN)<sub>6</sub>] (PBA). Both materials were characterized using XRD, IR, N<sub>2</sub> sorption and Raman spectroscopy. The results confirmed the conservation of MOF porosity after functionalization and the successful incorporation of PBA. Batch adsorption experiments were conducted to evaluate Cs <sup>+</sup> removal performance of the adsorbents. The study examined contact time (up to 1440 min), pH (2, 7 and 11), initial Cs<sup>+</sup> concentration (from 9 ppb to 1800 ppm) and competing ions. The resistance of the porous solids under drastic conditions involving gamma radiation (from 0.5 MGy up to10 MGy) was also investigated.</div><div>MI-101(Cr)-SO<sub>3</sub>H-PBA exhibited a maximum Cs <sup>+</sup> adsorption capacity of 242 mg.g<sub>MOF</sub><sup>−1</sup>, compared to 161 mg.g<sub>MOF</sub><sup>−1</sup> for pristine MIL-101(Cr)-SO<sub>3</sub>H and showed high selectivity toward Cs<sup>+</sup> in the presence of competing ions (Na<sup>+</sup>, K<sup>+</sup>, Mg<sup>2+</sup>, Ca<sup>2+</sup>, Sr<sup>2+</sup>). MI-101(Cr)-SO<sub>3</sub>H-PBA also demonstrates remarkable stability under radiation and alkaline conditions, maintaining 95 % efficiency, whereas the performance of pristine MIL-101(Cr)-SO<sub>3</sub>H material decreased significantly (7.5-fold decrease).</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"400 ","pages":"Article 113902"},"PeriodicalIF":4.7,"publicationDate":"2025-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145425239","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-21DOI: 10.1016/j.micromeso.2025.113899
Jaeyul Kim , Sunkyu Kim , Seungwan Seo , Raul F. Lobo , Jeffrey D. Rimer
Gallium nitride (GaN) has gained attention owing to its discovery as a thermal catalyst for non-oxidative aromatization of alkanes. Here, we discuss a new in situ method for generating extra-framework GaN encapsulated within the small pores of a Ga-chabazite (or Ga-CHA) zeolite. This is accomplished by the concerted demetallation of framework Ga in the presence of a nitrogen source (e.g., NH3 gas) at high temperature. This method involves nitridation through the decomposition of ammonia with concomitant extraction of framework gallium, forming GaN clusters within the cha cages. This approach avoids post-synthesis impregnation with GaN particles, which is challenging due to steric effects imposed by small-pore zeolites. GaN formation was validated by: (1) a visible shift in the color of extracted powders from white (H-Ga-CHA) to yellow ([GaN]-Ga-CHA), intensifying with increases in Ga content; (2) powder X-ray diffraction (PXRD), which confirmed peak shifts of framework Ga to those of GaN after treatment with ammonia; and (3) X-ray photoelectron spectroscopy (XPS). A series of [GaN]-Ga-CHA catalysts were prepared with different Ga content and were assessed in the ethane dehydrogenation (EDH) reaction. The parent sample, H-Ga-CHA, containing predominantly framework Ga, exhibits low activity. Conversely, the in situ generation of [Ga]-Ga-CHA containing extra-framework GaN exhibits higher initial rates of ethylene formation. Collectively, this study is a proof of principle for the method of scavenging metals in zeolites frameworks to generate multifunctional catalysts in situ, thereby circumventing the difficulties associated with encapsulating large active sites in small pores of zeolite catalysts.
{"title":"Formation of GaN in chabazite by scavenging framework gallium","authors":"Jaeyul Kim , Sunkyu Kim , Seungwan Seo , Raul F. Lobo , Jeffrey D. Rimer","doi":"10.1016/j.micromeso.2025.113899","DOIUrl":"10.1016/j.micromeso.2025.113899","url":null,"abstract":"<div><div>Gallium nitride (GaN) has gained attention owing to its discovery as a thermal catalyst for non-oxidative aromatization of alkanes. Here, we discuss a new <em>in situ</em> method for generating extra-framework GaN encapsulated within the small pores of a Ga-chabazite (or Ga-CHA) zeolite. This is accomplished by the concerted demetallation of framework Ga in the presence of a nitrogen source (e.g., NH<sub>3</sub> gas) at high temperature. This method involves nitridation through the decomposition of ammonia with concomitant extraction of framework gallium, forming GaN clusters within the <em>cha</em> cages. This approach avoids post-synthesis impregnation with GaN particles, which is challenging due to steric effects imposed by small-pore zeolites. GaN formation was validated by: (1) a visible shift in the color of extracted powders from white (H-Ga-CHA) to yellow ([GaN]-Ga-CHA), intensifying with increases in Ga content; (2) powder X-ray diffraction (PXRD), which confirmed peak shifts of framework Ga to those of GaN after treatment with ammonia; and (3) X-ray photoelectron spectroscopy (XPS). A series of [GaN]-Ga-CHA catalysts were prepared with different Ga content and were assessed in the ethane dehydrogenation (EDH) reaction. The parent sample, H-Ga-CHA, containing predominantly framework Ga, exhibits low activity. Conversely, the <em>in situ</em> generation of [Ga]-Ga-CHA containing extra-framework GaN exhibits higher initial rates of ethylene formation. Collectively, this study is a proof of principle for the method of scavenging metals in zeolites frameworks to generate multifunctional catalysts <em>in situ</em>, thereby circumventing the difficulties associated with encapsulating large active sites in small pores of zeolite catalysts.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"400 ","pages":"Article 113899"},"PeriodicalIF":4.7,"publicationDate":"2025-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145425234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-19DOI: 10.1016/j.micromeso.2025.113900
Peng Cheng , Guanzuo Liu , Li Ma , Binhao Yang , Xin You , Shuo Qi , Hongdan Zhang
In this work, we prepared hollow HZSM-5 encapsulating Pt nanoparticles catalysts uniformly covered with highly dispersed La2O3, which were applied to the catalytic cracking of iso-butane. The hollow structures reduced the possibility of secondary cracking of propylene products and improved the stability of the catalysts. More importantly, the synergistic effect of Pt nanoparticles and La2O3 further increased the selectivity of propylene in the products. The as-synthesized catalysts in terms of crystallinity, morphology, porosity, acid strength and distribution, and metal state were investigated in detail by a series of physicochemical characterizations. Pt nanoparticles promoted the synergistic dehydrogenation and cracking effect for iso-butane by activating C-C bonds and C-H bonds. The addition of La significantly affected the amounts of acid sites and acid type of catalysts, thereby increasing the propylene to ethylene (P/E) ratio of products in the catalytic cracking of iso-butane. The P/E ratio over Pt@Hol-HZSM-5-9 %La was 1.64, which was 2.34 times and 1.62 times over Pt@Hol-HZSM-5 and Hol-HZSM-5, respectively. Moreover, the hollow structures shortened the diffusion path of products and intermediates, and reduced the probability of hydrogen transfer reactions, which increased the selectivity of propylene and reduced the coke generation.
{"title":"La2O3 and Pt modified hollow ZSM-5 improving catalytic performance for iso-butane cracking","authors":"Peng Cheng , Guanzuo Liu , Li Ma , Binhao Yang , Xin You , Shuo Qi , Hongdan Zhang","doi":"10.1016/j.micromeso.2025.113900","DOIUrl":"10.1016/j.micromeso.2025.113900","url":null,"abstract":"<div><div>In this work, we prepared hollow HZSM-5 encapsulating Pt nanoparticles catalysts uniformly covered with highly dispersed La<sub>2</sub>O<sub>3</sub>, which were applied to the catalytic cracking of iso-butane. The hollow structures reduced the possibility of secondary cracking of propylene products and improved the stability of the catalysts. More importantly, the synergistic effect of Pt nanoparticles and La<sub>2</sub>O<sub>3</sub> further increased the selectivity of propylene in the products. The as-synthesized catalysts in terms of crystallinity, morphology, porosity, acid strength and distribution, and metal state were investigated in detail by a series of physicochemical characterizations. Pt nanoparticles promoted the synergistic dehydrogenation and cracking effect for iso-butane by activating C-C bonds and C-H bonds. The addition of La significantly affected the amounts of acid sites and acid type of catalysts, thereby increasing the propylene to ethylene (P/E) ratio of products in the catalytic cracking of iso-butane. The P/E ratio over Pt@Hol-HZSM-5-9 %La was 1.64, which was 2.34 times and 1.62 times over Pt@Hol-HZSM-5 and Hol-HZSM-5, respectively. Moreover, the hollow structures shortened the diffusion path of products and intermediates, and reduced the probability of hydrogen transfer reactions, which increased the selectivity of propylene and reduced the coke generation.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"400 ","pages":"Article 113900"},"PeriodicalIF":4.7,"publicationDate":"2025-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145334223","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zeolites, a cornerstone of the diverse porous framework materials and heterogeneous catalysis, continues to provide solutions for challenging organic transformations. Despite the tremendous advancements, still there remains room for extending the catalytic applications of zeolitic materials. Here we show the catalytic efficacy of silver exchanged zeolite-13X without the requirement of external base for the chemical fixation of carbon dioxide with propargylic alcohol derivatives (up to 99 %) at room temperature and atmospheric pressure conditions. Extensive characterization including Auger parameter discloses the presence of silver oxide in the zeolite environment. The experimental and NMR studies clearly depicts the synergistic role of catalyst and additive towards the formation of α-alkylidene cyclic carbonate. The choice of zeolite and solvent plays a crucial role in the catalytic chemical fixation of CO2 with propargylic alcohol derivatives.
{"title":"Silver species in the zeolite zone: Implications on catalytic fixation of CO2 with propargylic alcohol derivatives and mechanistic investigations","authors":"Manas Barik , Brijesh Patel , Shilpa Dabas , Parul Rathour , T.G. Ajithkumar , Palani S. Subramanian , Saravanan Subramanian","doi":"10.1016/j.micromeso.2025.113897","DOIUrl":"10.1016/j.micromeso.2025.113897","url":null,"abstract":"<div><div>Zeolites, a cornerstone of the diverse porous framework materials and heterogeneous catalysis, continues to provide solutions for challenging organic transformations. Despite the tremendous advancements, still there remains room for extending the catalytic applications of zeolitic materials. Here we show the catalytic efficacy of silver exchanged zeolite-13X without the requirement of external base for the chemical fixation of carbon dioxide with propargylic alcohol derivatives (up to 99 %) at room temperature and atmospheric pressure conditions. Extensive characterization including Auger parameter discloses the presence of silver oxide in the zeolite environment. The experimental and NMR studies clearly depicts the synergistic role of catalyst and additive towards the formation of α-alkylidene cyclic carbonate. The choice of zeolite and solvent plays a crucial role in the catalytic chemical fixation of CO<sub>2</sub> with propargylic alcohol derivatives.</div></div>","PeriodicalId":392,"journal":{"name":"Microporous and Mesoporous Materials","volume":"400 ","pages":"Article 113897"},"PeriodicalIF":4.7,"publicationDate":"2025-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145359749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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