Pub Date : 2026-01-07DOI: 10.1016/j.jcat.2026.116676
Haidong Zhang , Xin Wang , Feng Wang , Xiaohua Wang , Lishuang Ma , Xuequan Zhang , Heng Liu
cis-1,4-Polybutadiene (PBd) with ultra-high molecular weight typically exhibits significantly enhanced mechanical properties, including tear resistance, durability, and tensile strength, etc. Nevertheless, due to inevitable chain transfer reactions during polymerization, achieving such polymers currently remains a major challenge. In this work, we designed a series of α-diimine cobalt complexes featuring axial Co⋯H–C anagostic interactions. When being employed for butadiene polymerization, these complexes not only demonstrated high catalytic activity and excellent cis-1,4-selectivity, but also significantly suppressed chain transfer reactions, enabling the production of polybutadienes with ultra-high molecular weight, markedly exceeding those obtained from cobalt counterparts lacking such interactions.
{"title":"α-Diimine cobalt complexes bearing axial anagostic interaction: a system for accessing ultra-high molecular weight polybutadiene","authors":"Haidong Zhang , Xin Wang , Feng Wang , Xiaohua Wang , Lishuang Ma , Xuequan Zhang , Heng Liu","doi":"10.1016/j.jcat.2026.116676","DOIUrl":"10.1016/j.jcat.2026.116676","url":null,"abstract":"<div><div><em>cis</em>-1,4-Polybutadiene (PBd) with ultra-high molecular weight typically exhibits significantly enhanced mechanical properties, including tear resistance, durability, and tensile strength, etc. Nevertheless, due to inevitable chain transfer reactions during polymerization, achieving such polymers currently remains a major challenge. In this work, we designed a series of <em>α</em>-diimine cobalt complexes featuring axial Co⋯H–C anagostic interactions. When being employed for butadiene polymerization, these complexes not only demonstrated high catalytic activity and excellent <em>cis</em>-1,4-selectivity, but also significantly suppressed chain transfer reactions, enabling the production of polybutadienes with ultra-high molecular weight, markedly exceeding those obtained from cobalt counterparts lacking such interactions.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"455 ","pages":"Article 116676"},"PeriodicalIF":6.5,"publicationDate":"2026-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145908154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-06DOI: 10.1016/j.jcat.2026.116677
Yuyong Zhang , Yuanjun Zhao , Yuanyuan Zhu , Yudi Wu , Zhaozhan Wang , Jinglin Mu , Yong Yang
The integration of superior homogeneous catalytic activity with the practical advantages of facile separation and robust recyclability of heterogeneous systems remains a grand challenge. Here, we report a heterogenized bidentate phosphine ligand, constructed by integrating commercial Xantphos into a hypercrosslinked porous polymer, as a versatile platform for Pd-catalyzed alkoxycarbonylation. The tailored polymer, featuring a high surface area, hierarchical pores, and chemical robustness, provides privileged coordination microenvironments. It empowers highly efficient alkoxycarbonylation of diverse alkenes with various alcohols, including monoalcohols, diols, and polyols, to produce valuable esters with activity and selectivity comparable to its homogeneous molecular counterpart. Moreover, the catalytic system enables the in-situ formation of a robust Pd catalyst, wherein Pd nanoparticles are stabilized and uniformly dispersed via strong Pd-P coordination. This resulting catalyst demonstrates exceptional durability, being readily recycled over ten times without significant degradation in performance. This work pioneers a versatile platform for ligand immobilization that effectively bridges homogeneous efficiency with heterogeneous durability, unlocking efficient and sustainable pathways for carbonylation and other ligand-mediate transformations.
{"title":"Xantphos-derived porous polymer: a robust solid-state ligand for efficient Pd-catalyzed alkoxycarbonylation of alkenes from mono-alcohols to polyols","authors":"Yuyong Zhang , Yuanjun Zhao , Yuanyuan Zhu , Yudi Wu , Zhaozhan Wang , Jinglin Mu , Yong Yang","doi":"10.1016/j.jcat.2026.116677","DOIUrl":"10.1016/j.jcat.2026.116677","url":null,"abstract":"<div><div>The integration of superior homogeneous catalytic activity with the practical advantages of facile separation and robust recyclability of heterogeneous systems remains a grand challenge. Here, we report a heterogenized bidentate phosphine ligand, constructed by integrating commercial Xantphos into a hypercrosslinked porous polymer, as a versatile platform for Pd-catalyzed alkoxycarbonylation. The tailored polymer, featuring a high surface area, hierarchical pores, and chemical robustness, provides privileged coordination microenvironments. It empowers highly efficient alkoxycarbonylation of diverse alkenes with various alcohols, including monoalcohols, diols, and polyols, to produce valuable esters with activity and selectivity comparable to its homogeneous molecular counterpart. Moreover, the catalytic system enables the in-situ formation of a robust Pd catalyst, wherein Pd nanoparticles are stabilized and uniformly dispersed via strong Pd-P coordination. This resulting catalyst demonstrates exceptional durability, being readily recycled over ten times without significant degradation in performance. This work pioneers a versatile platform for ligand immobilization that effectively bridges homogeneous efficiency with heterogeneous durability, unlocking efficient and sustainable pathways for carbonylation and other ligand-mediate transformations.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"455 ","pages":"Article 116677"},"PeriodicalIF":6.5,"publicationDate":"2026-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145924007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-06DOI: 10.1016/j.jcat.2026.116678
Anna P. Khrychikova, Evgeniya V. Bermesheva, Nadezhda V. Nesterova, Anastasia A. Danshina, Yulia V. Nelyubina, Maxim V. Bermeshev
A series of cationic palladium complexes of the composition [(NHC)Pd(allyl)(PR3)]+BARF− containing N-heterocyclic carbene (NHC) and phosphine ligands of different nature, and a weakly coordinating borate anion were synthesized. Such Pd complexes were for the first time investigated as single-component catalysts for vinyl-addition polymerization of norbornene and its functionalized derivatives. The complexes exhibit high catalytic activity without the need for co-catalysts (to 7·106 gpolymer/molPd h). Polymers synthesized over these Pd complexes in question are characterized by unimodal GPC curves, narrow molecular weight distributions, and linear dependence of the molecular weight on the monomer conversion, which suggests the occurrence of controlled polymerization. It was demonstrated that both the structure of NHC and the nature of phosphine ligand have strong effect on catalytic activity and initiation efficiency. A correlation between Pd—P bond length and the behavior of the complex in the polymerization reaction was revealed, viz.: the shorter Pd—P bond the lower the lability of the phosphine, the initiation efficiency, and the higher the molecular weights of the resulting polymers. As a result, polymerization on the title complexes allows one to obtain polymers with much higher molecular weights compared to polymers synthesized using similar (NHC)Pd systems with other labile ligands. Besides, the synthesized complexes demonstrate high thermal stability and retain their catalytic activity at elevated temperatures. Generally, the presence of the NHC and phosphine ligands in palladium coordination sphere provides a unique balance between the activity, stability, and possibility to obtain high-molecular-weight products. This makes the complexes in hand promising catalysts for targeted synthesis of functional polymeric materials.
{"title":"Design of stable and active (NHC)Pd–phosphine catalysts for the synthesis of high-molecular-weight norbornene-based polymers","authors":"Anna P. Khrychikova, Evgeniya V. Bermesheva, Nadezhda V. Nesterova, Anastasia A. Danshina, Yulia V. Nelyubina, Maxim V. Bermeshev","doi":"10.1016/j.jcat.2026.116678","DOIUrl":"https://doi.org/10.1016/j.jcat.2026.116678","url":null,"abstract":"A series of cationic palladium complexes of the composition [(NHC)Pd(allyl)(PR<ce:inf loc=\"post\">3</ce:inf>)]<ce:sup loc=\"post\">+</ce:sup>BARF<ce:sup loc=\"post\">−</ce:sup> containing N-heterocyclic carbene (NHC) and phosphine ligands of different nature, and a weakly coordinating borate anion were synthesized. Such Pd complexes were for the first time investigated as single-component catalysts for vinyl-addition polymerization of norbornene and its functionalized derivatives. The complexes exhibit high catalytic activity without the need for co-catalysts (to 7·10<ce:sup loc=\"post\">6</ce:sup> g<ce:inf loc=\"post\">polymer</ce:inf>/mol<ce:inf loc=\"post\">Pd</ce:inf> h). Polymers synthesized over these Pd complexes in question are characterized by unimodal GPC curves, narrow molecular weight distributions, and linear dependence of the molecular weight on the monomer conversion, which suggests the occurrence of controlled polymerization. It was demonstrated that both the structure of NHC and the nature of phosphine ligand have strong effect on catalytic activity and initiation efficiency. A correlation between Pd—P bond length and the behavior of the complex in the polymerization reaction was revealed, <ce:italic>viz</ce:italic>.: the shorter Pd—P bond the lower the lability of the phosphine, the initiation efficiency, and the higher the molecular weights of the resulting polymers. As a result, polymerization on the title complexes allows one to obtain polymers with much higher molecular weights compared to polymers synthesized using similar (NHC)Pd systems with other labile ligands. Besides, the synthesized complexes demonstrate high thermal stability and retain their catalytic activity at elevated temperatures. Generally, the presence of the NHC and phosphine ligands in palladium coordination sphere provides a unique balance between the activity, stability, and possibility to obtain high-molecular-weight products. This makes the complexes in hand promising catalysts for targeted synthesis of functional polymeric materials.","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"37 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2026-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145956897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-06DOI: 10.1016/j.jcat.2026.116687
Brandon Elliott Oliphant, Zachary W. Meduna, J.Will Medlin
Mixed-aldol condensation of acetaldehyde and acetone was investigated over metal oxide and aluminosilicate catalysts to understand how changing the type of active site affects the selectivity of aldehyde-ketone cross-aldol condensation reactions. On TiO2 and MgO, where basic sites play a central role, high selectivity toward acetaldehyde self-condensation was observed. In contrast, reactions on the aluminosilicates, catalyzed by acid sites, had high selectivity toward the cross-condensation reaction. Temperature programmed desorption (TPD) studies showed that TiO2 binds acetaldehyde and its coupling products strongly, whereas acetone is adsorbed weakly enough to mostly undergo desorption without reaction. Similar studies on amorphous silica-alumina (ASA) showed the existence of both strongly bound acetaldehyde and strongly bound acetone, evidenced by the desorption of acetaldehyde and acetone coupling products. The discrepancy in reactant binding between surfaces is also supported by reaction order studies, which showed that on TiO2 acetone does not displace acetaldehyde from the catalyst surface, whereas on the aluminosilicate catalysts acetone readily displaces acetaldehyde. Kinetic isotope effect experiments showed that although selectivity is different across the two types of catalysts, C–H bond activation to form the nucleophilic enolate is likely kinetically relevant on both materials. High selectivity to cross-condensation was observed on HZSM-5 with a variety of SiO2:Al2O3 ratios, with kinetic results indicating a tradeoff between the number and strength of the active sites.
{"title":"The impact of active site character on the selectivity of aldehyde-ketone cross-aldol condensation reactions","authors":"Brandon Elliott Oliphant, Zachary W. Meduna, J.Will Medlin","doi":"10.1016/j.jcat.2026.116687","DOIUrl":"10.1016/j.jcat.2026.116687","url":null,"abstract":"<div><div>Mixed-aldol condensation of acetaldehyde and acetone was investigated over metal oxide and aluminosilicate catalysts to understand how changing the type of active site affects the selectivity of aldehyde-ketone cross-aldol condensation reactions. On TiO<sub>2</sub> and MgO, where basic sites play a central role, high selectivity toward acetaldehyde self-condensation was observed. In contrast, reactions on the aluminosilicates, catalyzed by acid sites, had high selectivity toward the cross-condensation reaction. Temperature programmed desorption (TPD) studies showed that TiO<sub>2</sub> binds acetaldehyde and its coupling products strongly, whereas acetone is adsorbed weakly enough to mostly undergo desorption without reaction. Similar studies on amorphous silica-alumina (ASA) showed the existence of both strongly bound acetaldehyde and strongly bound acetone, evidenced by the desorption of acetaldehyde and acetone coupling products. The discrepancy in reactant binding between surfaces is also supported by reaction order studies, which showed that on TiO<sub>2</sub> acetone does not displace acetaldehyde from the catalyst surface, whereas on the aluminosilicate catalysts acetone readily displaces acetaldehyde. Kinetic isotope effect experiments showed that although selectivity is different across the two types of catalysts, C–H bond activation to form the nucleophilic enolate is likely kinetically relevant on both materials. High selectivity to cross-condensation was observed on HZSM-5 with a variety of SiO<sub>2</sub>:Al<sub>2</sub>O<sub>3</sub> ratios, with kinetic results indicating a tradeoff between the number and strength of the active sites.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"455 ","pages":"Article 116687"},"PeriodicalIF":6.5,"publicationDate":"2026-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145920474","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-06DOI: 10.1016/j.jcat.2025.116661
Yishuang Wang , Lei Liu , Mingqiang Chen , Defang Liang , Chang Li , Jun Wang , Haosheng Xin
Lignin valorization is crucial for obtaining sustainable fuels and chemicals, however its complex structure challenges efficient conversion. Herein, we designed a Ru-modified Co/attapulgite (CoRux/ATP) catalysts for achieving the catalytic depolymerization of lignin (CDL) under ethanol coupled with H2 medium to liquid fuel and guaiacols. CoRu1/ATP exhibited exceptional catalytic efficiency under optimal conditions, where the yields of liquid product and guaiacols reached 82.82% and 584.67 mg/g, respectively. Experiments with model compounds demonstrated that the addition of Ru could effectively reduce the activation energy of the β-O-4 bond cleavage, which decreased from 78.6 kJ·mol−1 to 73.5 kJ·mol−1. Characterization results indicated that the Ru additive yielded Co–Ru interfaces and its hydrogen spillover effect promoted the reduction of Co3O4 to CoO and metallic Co (Co0) to produce more oxygen vacancies (VO). Additionally, the research on reaction mechanisms revealed VO and CoO phases in CoRu1/ATP enhanced the breakage of C–O bonds of lignin and the adjacent metallic Co and Ru sites and Co–Ru interfaces improved the activation of ethanol and molecular hydrogen into active hydrogen (H*) species to stabilize reactive intermediates and enhance hydrogenation reaction. The findings provide a potential method for directional lignin conversion.
{"title":"Efficient depolymerization of lignin over Ru-modified Co/attapulgite: Construct of abundant activated hydrogen source sites","authors":"Yishuang Wang , Lei Liu , Mingqiang Chen , Defang Liang , Chang Li , Jun Wang , Haosheng Xin","doi":"10.1016/j.jcat.2025.116661","DOIUrl":"10.1016/j.jcat.2025.116661","url":null,"abstract":"<div><div>Lignin valorization is crucial for obtaining sustainable fuels and chemicals, however its complex structure challenges efficient conversion. Herein, we designed a Ru-modified Co/attapulgite (CoRu<sub>x</sub>/ATP) catalysts for achieving the catalytic depolymerization of lignin (CDL) under ethanol coupled with H<sub>2</sub> medium to liquid fuel and guaiacols. CoRu<sub>1</sub>/ATP exhibited exceptional catalytic efficiency under optimal conditions, where the yields of liquid product and guaiacols reached 82.82% and 584.67 mg/g, respectively. Experiments with model compounds demonstrated that the addition of Ru could effectively reduce the activation energy of the β-O-4 bond cleavage, which decreased from 78.6 kJ·mol<sup>−1</sup> to 73.5 kJ·mol<sup>−1</sup>. Characterization results indicated that the Ru additive yielded Co–Ru interfaces and its hydrogen spillover effect promoted the reduction of Co<sub>3</sub>O<sub>4</sub> to CoO and metallic Co (Co<sup>0</sup>) to produce more oxygen vacancies (V<sub>O</sub>). Additionally, the research on reaction mechanisms revealed V<sub>O</sub> and CoO phases in CoRu<sub>1</sub>/ATP enhanced the breakage of C–O bonds of lignin and the adjacent metallic Co and Ru sites and Co–Ru interfaces improved the activation of ethanol and molecular hydrogen into active hydrogen (H*) species to stabilize reactive intermediates and enhance hydrogenation reaction. The findings provide a potential method for directional lignin conversion.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"455 ","pages":"Article 116661"},"PeriodicalIF":6.5,"publicationDate":"2026-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145908156","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-06DOI: 10.1016/j.jcat.2026.116673
Jorge Ferreira Jr. , Gabriela Uez , Arthur L. Schmidt , Camila Ebersol , Bianca T. Dalberto , Daniel F. Pietezak , Robson S. Oliboni , Angélica V. Moro , Diogo S. Lüdtke , Adriana C.A. Casagrande , Fabiano S. Rodembusch , Pedro Migowski , Osvaldo L. Casagrande Jr.
We report the design, synthesis, and comprehensive characterization of a new series of iron(II) complexes bearing bis(pyrazolyl)phenantroline ligands, developed as homogeneous catalysts for the visible-light-driven reduction of CO2 to CO. All complexes adopt high-spin quintet ground states and exhibit distorted octahedral geometries, with redox processes primarily localized on the ligand framework. Spectroscopic data and theoretical modeling revealed that the optical absorption in the UV region arises from ligand-centered π–π* transitions, while the weaker red-shifted bands are attributed to forbidden transitions. Electrochemical analyses confirmed ligand-centered reductions across the series, modulated by the electronic nature of the pyrazolyl substituents. All iron complexes were active for photocatalytic reduction of CO2 to CO. Among them, Fe2 showed the highest overall activity, reaching a TONCO of 1318 and CO selectivity of 84 %. Notably, Fe4 achieved a high TONCO of 1265 and CO selectivity of 91 % in the series. Systematic variation of reaction parameters using Fe2 allowed the identification of optimal conditions for maximizing catalytic efficiency and product selectivity. At lower catalyst loadings, Fe2 achieved the highest TONCO (up to 23,138) and CO selectivity (up to 91 %). Additionally, the presence of 7.5–10 % water proved essential for effective proton-coupled electron transfer and stabilization of intermediates. Mechanistic studies, including control and Hg poisoning experiments, confirmed the homogeneous nature and robustness of the catalytic system, with deactivation arising mainly from photosensitizer deterioration. Fe2 reached a TONCO of 9754 after 4 h of irradiation (λ = 462 nm), corresponding to a TOF of 2438 h−1 and a total quantum yield of 8.24 %.
{"title":"Iron(II) bis(pyrazolyl)phenanthroline complexes as robust and efficient homogeneous catalysts for CO2-to-CO conversion under visible light","authors":"Jorge Ferreira Jr. , Gabriela Uez , Arthur L. Schmidt , Camila Ebersol , Bianca T. Dalberto , Daniel F. Pietezak , Robson S. Oliboni , Angélica V. Moro , Diogo S. Lüdtke , Adriana C.A. Casagrande , Fabiano S. Rodembusch , Pedro Migowski , Osvaldo L. Casagrande Jr.","doi":"10.1016/j.jcat.2026.116673","DOIUrl":"10.1016/j.jcat.2026.116673","url":null,"abstract":"<div><div>We report the design, synthesis, and comprehensive characterization of a new series of iron(II) complexes bearing bis(pyrazolyl)phenantroline ligands, developed as homogeneous catalysts for the visible-light-driven reduction of CO<sub>2</sub> to CO. All complexes adopt high-spin quintet ground states and exhibit distorted octahedral geometries, with redox processes primarily localized on the ligand framework. Spectroscopic data and theoretical modeling revealed that the optical absorption in the UV region arises from ligand-centered π–π* transitions, while the weaker red-shifted bands are attributed to forbidden transitions. Electrochemical analyses confirmed ligand-centered reductions across the series, modulated by the electronic nature of the pyrazolyl substituents. All iron complexes were active for photocatalytic reduction of CO<sub>2</sub> to CO. Among them, <strong>Fe2</strong> showed the highest overall activity, reaching a TON<sub>CO</sub> of 1318 and CO selectivity of 84 %. Notably, <strong>Fe4</strong> achieved a high TON<sub>CO</sub> of 1265 and CO selectivity of 91 % in the series. Systematic variation of reaction parameters using <strong>Fe2</strong> allowed the identification of optimal conditions for maximizing catalytic efficiency and product selectivity. At lower catalyst loadings, <strong>Fe2</strong> achieved the highest TON<sub>CO</sub> (up to 23,138) and CO selectivity (up to 91 %). Additionally, the presence of 7.5–10 % water proved essential for effective proton-coupled electron transfer and stabilization of intermediates. Mechanistic studies, including control and Hg poisoning experiments, confirmed the homogeneous nature and robustness of the catalytic system, with deactivation arising mainly from photosensitizer deterioration. <strong>Fe2</strong> reached a TON<sub>CO</sub> of 9754 after 4 h of irradiation (λ = 462 nm), corresponding to a TOF of 2438 h<sup>−1</sup> and a total quantum yield of 8.24 %.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"455 ","pages":"Article 116673"},"PeriodicalIF":6.5,"publicationDate":"2026-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145908190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-06DOI: 10.1016/j.jcat.2026.116669
Giuseppe Antinucci, Felicia Daniela Cannavacciuolo, Roberta Cipullo, Vincenzo Busico
Ziegler-Natta (ZN) catalysts for stereoselective propene polymerization originated as relatively simple mixtures of crystalline TiCl3 in a layered modification and an Al-alkyl activator. At a later stage, to enhance productivity with respect to Ti and decrease the amount of acidic Ti–Cl residues in the polymer, supported versions were introduced in which TiCl4 is adsorbed on a nanocrystalline MgCl2 matrix and subsequently alkylated and reduced by AlEt3. The addition of certain organic electron donors to the solid precatalyst (‘Internal Donor’, ID) and, in most cases, to AlEt3 (‘External Donor’, ED) is mandatory to achieve a high stereoselectivity, but how donor modification works in detail is not well understood. For several decades now the models of catalytic species for Mg–Ti systems have been inspired by the structural similarity between the layer lattices of MgCl2 and TiCl3, which led many to propose that the active site precursors are epitaxial TiCl4 adsorbates with coordinatively saturated octahedral Ti, and hence no room left for direct Ti-Donor bonding interactions. In the present communication, based on state-of-the-art Density Functional Theory calculations and topological analyses of the surface, we show that the hypothesis of non-epitaxial TiCl4-ID adducts with ID molecules directly bonded to the active Ti is in much better agreement with the experimental facts. Breaking the paradigm of epitaxy leads to redefine structure-properties relations for these important catalysts, and can change the strategy of donor design.
{"title":"Ziegler-Natta catalysts for polypropylene: breaking the paradigm of epitaxy","authors":"Giuseppe Antinucci, Felicia Daniela Cannavacciuolo, Roberta Cipullo, Vincenzo Busico","doi":"10.1016/j.jcat.2026.116669","DOIUrl":"10.1016/j.jcat.2026.116669","url":null,"abstract":"<div><div>Ziegler-Natta (ZN) catalysts for stereoselective propene polymerization originated as relatively simple mixtures of crystalline TiCl<sub>3</sub> in a layered modification and an Al-alkyl activator. At a later stage, to enhance productivity with respect to Ti and decrease the amount of acidic Ti–Cl residues in the polymer, supported versions were introduced in which TiCl<sub>4</sub> is adsorbed on a nanocrystalline MgCl<sub>2</sub> matrix and subsequently alkylated and reduced by AlEt<sub>3</sub>. The addition of certain organic electron donors to the solid precatalyst (‘Internal Donor’, ID) and, in most cases, to AlEt<sub>3</sub> (‘External Donor’, ED) is mandatory to achieve a high stereoselectivity, but how donor modification works in detail is not well understood. For several decades now the models of catalytic species for Mg–Ti systems have been inspired by the structural similarity between the layer lattices of MgCl<sub>2</sub> and TiCl<sub>3</sub>, which led many to propose that the active site precursors are epitaxial TiCl<sub>4</sub> adsorbates with coordinatively saturated octahedral Ti, and hence no room left for direct Ti-Donor bonding interactions. In the present communication, based on state-of-the-art Density Functional Theory calculations and topological analyses of the surface, we show that the hypothesis of non-epitaxial TiCl<sub>4</sub>-ID adducts with ID molecules directly bonded to the active Ti is in much better agreement with the experimental facts. Breaking the paradigm of epitaxy leads to redefine structure-properties relations for these important catalysts, and can change the strategy of donor design.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"455 ","pages":"Article 116669"},"PeriodicalIF":6.5,"publicationDate":"2026-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145923545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-06DOI: 10.1016/j.jcat.2026.116675
Xin Chen, Shuaihu Geng, Yunhao Zhou, Kun Zhao, Jiahong Li, Sheng-Yin Zhao, Weiping Liu
Manganese catalysis is emerging as a sustainable alternative to noble metals in homogeneous catalysis. Although manganese-catalyzed asymmetric hydrophosphination has been well established for C-stereogenic phosphines, the enantioselective synthesis of P-stereogenic phosphines remains challenging. Herein, we report a novel manganese-catalyzed asymmetric hydrophosphination of electron-deficient alkenes, enabling the synthesis of diverse P-stereogenic phosphines with good to excellent yields and enantioselectivities, demonstrating broad functional group tolerance. Mechanistic investigations using 31P NMR analysis support a metal–ligand-cooperation pathway for H-P bond activation by manganese catalyst.
{"title":"Asymmetric hydrophosphination for P-stereogenic phosphines enabled by manganese catalysis","authors":"Xin Chen, Shuaihu Geng, Yunhao Zhou, Kun Zhao, Jiahong Li, Sheng-Yin Zhao, Weiping Liu","doi":"10.1016/j.jcat.2026.116675","DOIUrl":"10.1016/j.jcat.2026.116675","url":null,"abstract":"<div><div>Manganese catalysis is emerging as a sustainable alternative to noble metals in homogeneous catalysis. Although manganese-catalyzed asymmetric hydrophosphination has been well established for <em>C</em>-stereogenic phosphines, the enantioselective synthesis of <em>P</em>-stereogenic phosphines remains challenging. Herein, we report a novel manganese-catalyzed asymmetric hydrophosphination of electron-deficient alkenes, enabling the synthesis of diverse <em>P</em>-stereogenic phosphines with good to excellent yields and enantioselectivities, demonstrating broad functional group tolerance. Mechanistic investigations using <sup>31</sup>P NMR analysis support a metal–ligand-cooperation pathway for H-P bond activation by manganese catalyst.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"455 ","pages":"Article 116675"},"PeriodicalIF":6.5,"publicationDate":"2026-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145908153","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-06DOI: 10.1016/j.jcat.2026.116686
Ni Yi , Qi Xiao , Jilun Song, Shulin Wang, Yingru Wang, Liang Cao
Rational design of multicomponent alloy electrocatalysts is complicated by vast composition space and finite-temperature surface disorder. Here we develop a multiscale framework that links surface thermodynamics to site-resolved energetics for Ag–Au–Cu–Pd–Pt high-entropy alloy (HEA) nanoparticles in CO2-to-CO reduction. A cluster-expansion Hamiltonian combined with Metropolis Monte Carlo sampling captures temperature-dependent surface segregation and generates realistic equilibrium surface structures. A compact, strain-aware neural network trained on DFT *CO adsorption energies—using ligand, coordination, and strain descriptors—enables high-throughput prediction of adsorption energetics across diverse local environments. Coupled via a Sabatier-type volcano, these predictions yield composition–activity maps that reveal a robust Cu-rich activity window (75–85%). Representative formulations such as Cu0.85Pt0.15 and Ag0.05Au0.05Cu0.8Pt0.05Pd0.05 exhibit up to ∼5-fold and ∼10-fold higher activity than Cu(111) and equimolar HEAs, respectively, after annealing at 1500 K. DFT-validated analysis identifies a transferable local motif—Cu-atop sites embedded in Cu-enriched first- and second-neighbor shells—that tunes *CO binding toward the volcano optimum and rationalizes the Cu-rich activity ridges. Treating “high entropy” as a design strategy rather than a strict composition rule provides experimentally accessible composition windows and annealing conditions, as well as a reusable workflow for optimizing multicomponent alloy electrocatalysts.
{"title":"Finite-temperature composition–activity maps reveal Cu-rich windows for CO2-to-CO reduction on Ag–Au–Cu–Pd–Pt high-entropy alloys","authors":"Ni Yi , Qi Xiao , Jilun Song, Shulin Wang, Yingru Wang, Liang Cao","doi":"10.1016/j.jcat.2026.116686","DOIUrl":"10.1016/j.jcat.2026.116686","url":null,"abstract":"<div><div>Rational design of multicomponent alloy electrocatalysts is complicated by vast composition space and finite-temperature surface disorder. Here we develop a multiscale framework that links surface thermodynamics to site-resolved energetics for Ag–Au–Cu–Pd–Pt high-entropy alloy (HEA) nanoparticles in CO<sub>2</sub>-to-CO reduction. A cluster-expansion Hamiltonian combined with Metropolis Monte Carlo sampling captures temperature-dependent surface segregation and generates realistic equilibrium surface structures. A compact, strain-aware neural network trained on DFT *CO adsorption energies—using ligand, coordination, and strain descriptors—enables high-throughput prediction of adsorption energetics across diverse local environments. Coupled via a Sabatier-type volcano, these predictions yield composition–activity maps that reveal a robust Cu-rich activity window (75–85%). Representative formulations such as Cu<sub>0.85</sub>Pt<sub>0.15</sub> and Ag<sub>0.05</sub>Au<sub>0.05</sub>Cu<sub>0.8</sub>Pt<sub>0.05</sub>Pd<sub>0.05</sub> exhibit up to ∼5-fold and ∼10-fold higher activity than Cu(111) and equimolar HEAs, respectively, after annealing at 1500 K. DFT-validated analysis identifies a transferable local motif—Cu-atop sites embedded in Cu-enriched first- and second-neighbor shells—that tunes *CO binding toward the volcano optimum and rationalizes the Cu-rich activity ridges. Treating “high entropy” as a design strategy rather than a strict composition rule provides experimentally accessible composition windows and annealing conditions, as well as a reusable workflow for optimizing multicomponent alloy electrocatalysts.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"455 ","pages":"Article 116686"},"PeriodicalIF":6.5,"publicationDate":"2026-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145924008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-05DOI: 10.1016/j.jcat.2026.116672
Wanyi Li , Wenbiao Zhang , He Li , Yi Tang , Yahong Zhang
Molybdenum disulfide (MoS2) holds promise in catalysis due to its edge-confined activity, but its structural rigidity and strong in-plane Mo-S bonding limit the exposure of active sites. Herein, we propose a high-curvature support-induced method using ultrasmall ZSM-5 subcrystals (Z-5-SC) to tailor the formation of NiMoS2 on them. The high curvature and abundant external silanol groups of Z-5-SC induce tensile strain and strong interfacial anchoring, generating short and curved NiMoS2 slabs with enhanced sulfur vacancies and Ni-Mo-S phase formation. Compared to nanocrystalline zeolite supports, the NiMoS2/Z-5-SC exhibits 7.3-fold higher hydrodesulfurization (HDS) activity toward 4,6-dimethyldibenzothiophene (kHDS = 0.624 h−1), rapid hydrodenitrogenation (HDN) response with minimized HDS suppression in simultaneous HDS and HDN reactions, and excellent cycling stability over 15 cycles. This work presents an effective curvature-engineering strategy to enhance the catalytic potential of MoS2, offering new insights into the design of engineered two-dimensional materials for hydrotreating and beyond.
{"title":"Zeolite subcrystal-induced formation of short and curved NiMoS2 slabs toward highly efficient hydrodesulfurization","authors":"Wanyi Li , Wenbiao Zhang , He Li , Yi Tang , Yahong Zhang","doi":"10.1016/j.jcat.2026.116672","DOIUrl":"10.1016/j.jcat.2026.116672","url":null,"abstract":"<div><div>Molybdenum disulfide (MoS<sub>2</sub>) holds promise in catalysis due to its edge-confined activity, but its structural rigidity and strong in-plane Mo-S bonding limit the exposure of active sites. Herein, we propose a high-curvature support-induced method using ultrasmall ZSM-5 subcrystals (Z-5-SC) to tailor the formation of NiMoS<sub>2</sub> on them. The high curvature and abundant external silanol groups of Z-5-SC induce tensile strain and strong interfacial anchoring, generating short and curved NiMoS<sub>2</sub> slabs with enhanced sulfur vacancies and Ni-Mo-S phase formation. Compared to nanocrystalline zeolite supports, the NiMoS<sub>2</sub>/Z-5-SC exhibits 7.3-fold higher hydrodesulfurization (HDS) activity toward 4,6-dimethyldibenzothiophene (<em>k<sub>HDS</sub></em> = 0.624 h<sup>−1</sup>), rapid hydrodenitrogenation (HDN) response with minimized HDS suppression in simultaneous HDS and HDN reactions, and excellent cycling stability over 15 cycles. This work presents an effective curvature-engineering strategy to enhance the catalytic potential of MoS<sub>2</sub>, offering new insights into the design of engineered two-dimensional materials for hydrotreating and beyond.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"455 ","pages":"Article 116672"},"PeriodicalIF":6.5,"publicationDate":"2026-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145903496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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