Pub Date : 2025-01-15DOI: 10.1016/j.jcat.2025.115967
Dan Zhou, Chengxiong Dang, Xiaopeng Chen, Linlin Wang, Weiquan Cai
Reaction mechanism is crucial for understanding, applying, and optimizing the carboxylic acid esterification. This review discusses the possible carboxylic acid esterification mechanisms, including homogeneous acid-catalyzed acyloxy/alkoxy bond cleavage, heterogeneous single/dual-site acid/base, and dual-site acid-base synergistic catalysis. The physical means, applications, and limitations of quasi-homogeneous (QH), Eley-Rideal (ER), Langmuir-Hinshelwood-Hougen-Watson (LH), Hattori (H), and their modified models were summarized. Since the similarity or significant difference in adsorption performance of reactants may lead to parameter dependence (e.g., different ER type variants) or overparametrization (e.g., LH model), and kinetic studies cannot identify active sites and intermediates, thus insufficiently revealing a detailed heterogeneous esterification mechanism. The applications of characterization techniques in revealing active sites, adsorption mechanisms, and chemical bond evolution were discussed to verify and compensate for kinetic results. Density functional theory calculations and microkinetic modeling were also outlined to give atomistic-level insights. Furthermore, the use of enzymes and solvents in the esterification was outlined.
{"title":"Characterization and theoretical calculations as powerful compensators for kinetics in the study of heterogeneous catalytic mechanisms on esterifying carboxylic acid","authors":"Dan Zhou, Chengxiong Dang, Xiaopeng Chen, Linlin Wang, Weiquan Cai","doi":"10.1016/j.jcat.2025.115967","DOIUrl":"https://doi.org/10.1016/j.jcat.2025.115967","url":null,"abstract":"Reaction mechanism is crucial for understanding, applying, and optimizing the carboxylic acid esterification. This review discusses the possible carboxylic acid esterification mechanisms, including homogeneous acid-catalyzed acyloxy/alkoxy bond cleavage, heterogeneous single/dual-site acid/base, and dual-site acid-base synergistic catalysis. The physical means, applications, and limitations of quasi-homogeneous (QH), Eley-Rideal (ER), Langmuir-Hinshelwood-Hougen-Watson (LH), Hattori (H), and their modified models were summarized. Since the similarity or significant difference in adsorption performance of reactants may lead to parameter dependence (e.g., different ER type variants) or overparametrization (e.g., LH model), and kinetic studies cannot identify active sites and intermediates, thus insufficiently revealing a detailed heterogeneous esterification mechanism. The applications of characterization techniques in revealing active sites, adsorption mechanisms, and chemical bond evolution were discussed to verify and compensate for kinetic results. Density functional theory calculations and microkinetic modeling were also outlined to give atomistic-level insights. Furthermore, the use of enzymes and solvents in the esterification was outlined.","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"68 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142986774","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 : 2025-01-14DOI: 10.1016/j.jcat.2025.115944
Sakshi Bhatt, Sandhya Saini, B. Moses Abraham, Anil Malik, Arghya sen, Suman L. Jain
The authors regret Revise the Affiliation of corresponding author from “Suman L Jain *a to Suman L Jain *a,b in the Published article. As the corresponding author is also affiliated from AcSIR as an associate professor.
作者遗憾地将已发表文章中通讯作者的隶属关系从 "Suman L Jain *a "修改为 "Suman L Jain *a,b"。因为通讯作者也是 AcSIR 的副教授。
{"title":"Corrigendum to “Heterostructured Ti-MOF/g-C3N4 driven light assisted reductive carboxylation of aryl aldehydes with CO2 under ambient conditions” [J. Catal. 417 (2023) 116–128]","authors":"Sakshi Bhatt, Sandhya Saini, B. Moses Abraham, Anil Malik, Arghya sen, Suman L. Jain","doi":"10.1016/j.jcat.2025.115944","DOIUrl":"https://doi.org/10.1016/j.jcat.2025.115944","url":null,"abstract":"The authors regret Revise the Affiliation of corresponding author from “Suman L Jain *a to Suman L Jain *a,b in the Published article. As the corresponding author is also affiliated from AcSIR as an associate professor.","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"52 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142975513","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 : 2025-01-14DOI: 10.1016/j.jcat.2025.115947
Shengchao Jia, Tao Tong, Xiaohui Liu, Yong Guo, Lin Dong, Zupeng Chen, Yanqin Wang
We are sorry that we have found a minor error in our published paper entitiled “Identifying a superior Ptδ+ species for the hydrogen-borrowing amination of alcohol at low temperature” (J. Catal. 432 (2024) 115407). Although it is not critical data and does not affect the corresponding conclusion, we still hope a smooth corrigendum to ensure its rigor.
{"title":"Corrigendum to “Identifying a superior Ptδ+ species for the hydrogen-borrowing amination of alcohol at low temperature” [J. Catal. 432 (2024) 115407]","authors":"Shengchao Jia, Tao Tong, Xiaohui Liu, Yong Guo, Lin Dong, Zupeng Chen, Yanqin Wang","doi":"10.1016/j.jcat.2025.115947","DOIUrl":"https://doi.org/10.1016/j.jcat.2025.115947","url":null,"abstract":"We are sorry that we have found a minor error in our published paper entitiled “Identifying a superior Pt<sup>δ+</sup> species for the hydrogen-borrowing amination of alcohol at low temperature” (J. Catal. 432 (2024) 115407). Although it is not critical data and does not affect the corresponding conclusion, we still hope a smooth corrigendum to ensure its rigor.","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"7 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142975362","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 : 2025-01-13DOI: 10.1016/j.jcat.2025.115965
Isaac O. Ogabiela, Friederike C. Jentoft
Aldol reactions are important in chemical syntheses and have high potential for use in the conversion of biomass to fuels and chemicals. Zeolites of various framework topologies (MFI, MWW, MOR, BEA, FAU) were investigated for their ability to direct aldol chemistry towards the dehydration and formation of the classical condensation product, or towards fission to an olefin and a carboxylic acid. The performance of these solid acids was benchmarked against homogeneous catalysis by benzenesulfonic acid. At reaction temperatures between 80 °C and 180 °C, autogenous pressure in toluene as the solvent, the zeolite-catalyzed cross-aldol reaction between benzaldehyde and 3-pentanone gave the fission products β-methyl-styrene and propionic acid with selectivity of up to 99 %, whereas catalysis by benzenesulfonic acid resulted in the dehydration product 2-methyl-1-phenyl-1-penten-3-one with a selectivity of 100 %. Selectivity-conversion analysis showed fission and dehydration to be parallel reactions of the intermediate ketol 1-hydroxy-2-methyl-1-phenyl-3-pentanone. Poisoning experiments with pyridine, 2,6-lutidine, triphenylphosphine and 2,4,6 tri-tert-butylpyridine demonstrate that fission is catalyzed by Brønsted acid sites and occurs in the zeolite interior of FAU and BEA, in the external cups of MWW, and to some extent in the pore mouths of all topologies. Arrhenius analysis revealed an activation energy of 107 ± 2 kJ/mol for fission in FAU. Fission selectivity in zeolites is found to be enhanced by the inability of the dehydration product to leave the pores. In the reaction-controlled regime, as determined by Weisz-Prater analysis and inspection of the Arrhenius plot, the fission rate is independent of the site density over a wide range of compositions (Si/Al from 6 to 40 for FAU). This result is interpreted as a limitation through molecular crowding in the pores, which prevents full participation of all sites in a cage. The high yields achievable to either product at maximum conversion – up to 85 % fission or 90 % dehydration – simply by choice of catalyst make acid catalysis an attractive choice in aldol chemistry.
{"title":"Insights into effects of zeolite framework topology on the cross aldol reaction of benzaldehyde with 3-Pentanone","authors":"Isaac O. Ogabiela, Friederike C. Jentoft","doi":"10.1016/j.jcat.2025.115965","DOIUrl":"https://doi.org/10.1016/j.jcat.2025.115965","url":null,"abstract":"Aldol reactions are important in chemical syntheses and have high potential for use in the conversion of biomass to fuels and chemicals. Zeolites of various framework topologies (MFI, MWW, MOR, BEA, FAU) were investigated for their ability to direct aldol chemistry towards the dehydration and formation of the classical condensation product, or towards fission to an olefin and a carboxylic acid. The performance of these solid acids was benchmarked against homogeneous catalysis by benzenesulfonic acid. At reaction temperatures between 80 °C and 180 °C, autogenous pressure in toluene as the solvent, the zeolite-catalyzed cross-aldol reaction between benzaldehyde and 3-pentanone gave the fission products β-methyl-styrene and propionic acid with selectivity of up to 99 %, whereas catalysis by benzenesulfonic acid resulted in the dehydration product 2-methyl-1-phenyl-1-penten-3-one with a selectivity of 100 %. Selectivity-conversion analysis showed fission and dehydration to be parallel reactions of the intermediate ketol 1-hydroxy-2-methyl-1-phenyl-3-pentanone. Poisoning experiments with pyridine, 2,6-lutidine, triphenylphosphine and 2,4,6 tri-<em>tert</em>-butylpyridine demonstrate that fission is catalyzed by Brønsted acid sites and occurs in the zeolite interior of FAU and BEA, in the external cups of MWW, and to some extent in the pore mouths of all topologies. Arrhenius analysis revealed an activation energy of 107 ± 2 kJ/mol for fission in FAU. Fission selectivity in zeolites is found to be enhanced by the inability of the dehydration product to leave the pores. In the reaction-controlled regime, as determined by Weisz-Prater analysis and inspection of the Arrhenius plot, the fission rate is independent of the site density over a wide range of compositions (Si/Al from 6 to 40 for FAU). This result is interpreted as a limitation through molecular crowding in the pores, which prevents full participation of all sites in a cage. The high yields achievable to either product at maximum conversion – up to 85 % fission or 90 % dehydration – simply by choice of catalyst make acid catalysis an attractive choice in aldol chemistry.","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"36 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142975515","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 : 2025-01-13DOI: 10.1016/j.jcat.2025.115959
Mingzhu Yue, Wenfu Xie, Ziyi Zhong, Min Li, Tianyu Zhang, Mingfei Shao, Hao Li, Qiang Wang
Electrocatalytic CO2 reduction reaction (CO2RR) to CH4 presents an effective solution to environmental and energy challenges. Catalysts featuring monodispersed Cu sites can suppress the dimerization of *CO intermediate, which makes them promising candidates for achieving high selectivity in the deep reduction of CO2 to CH4. However, most Cu-based catalysts inevitably undergo restructuring during the reaction, which can alter the CO2 reduction pathway and result in decreased performance. In this study, a series of Cu-based layered double hydroxides (LDHs) with stable monodispersed Cu sites were developed via atom isolation strategy. Among them, the CuMgAl-LDH catalyst with the monodispersed Cu sites achieved a Faradaic efficiency (FE) of 58.9 % for CO2 reduction to CH4 at a current density of 300 mA cm−2 in a flow cell. In contrast, the CuAl-LDH catalyst without Mg doping showed a FE of 40.5 % for CO2 reduction to C2H4. The results indicate that Mg atoms can inhibit the reconstruction process of CuMgAl-LDH during working conditions, preventing the aggregation of Cu atoms, thereby maintaining a high dispersion of Cu atoms. Additionally, a pulse electrolysis regulation strategy was employed to further enhance the selectivity and stability of CuMgAl-LDH, achieving a FE of 71.6 % for CO2 reduction to CH4, with stability maintained for over 13 h. The results present a useful case for studying catalyst reconstruction and improving CO2 reduction performance.
{"title":"Isolating and stabilizing active copper species in layered double hydroxide to enhance electrocatalytic CO2 reduction to CH4","authors":"Mingzhu Yue, Wenfu Xie, Ziyi Zhong, Min Li, Tianyu Zhang, Mingfei Shao, Hao Li, Qiang Wang","doi":"10.1016/j.jcat.2025.115959","DOIUrl":"https://doi.org/10.1016/j.jcat.2025.115959","url":null,"abstract":"Electrocatalytic CO<sub>2</sub> reduction reaction (CO<sub>2</sub>RR) to CH<sub>4</sub> presents an effective solution to environmental and energy challenges. Catalysts featuring monodispersed Cu sites can suppress the dimerization of *CO intermediate, which makes them promising candidates for achieving high selectivity in the deep reduction of CO<sub>2</sub> to CH<sub>4</sub>. However, most Cu-based catalysts inevitably undergo restructuring during the reaction, which can alter the CO<sub>2</sub> reduction pathway and result in decreased performance. In this study, a series of Cu-based layered double hydroxides (LDHs) with stable monodispersed Cu sites were developed via atom isolation strategy. Among them, the CuMgAl-LDH catalyst with the monodispersed Cu sites achieved a Faradaic efficiency (FE) of 58.9 % for CO<sub>2</sub> reduction to CH<sub>4</sub> at a current density of 300 mA cm<sup>−2</sup> in a flow cell. In contrast, the CuAl-LDH catalyst without Mg doping showed a FE of 40.5 % for CO<sub>2</sub> reduction to C<sub>2</sub>H<sub>4</sub>. The results indicate that Mg atoms can inhibit the reconstruction process of CuMgAl-LDH during working conditions, preventing the aggregation of Cu atoms, thereby maintaining a high dispersion of Cu atoms. Additionally, a pulse electrolysis regulation strategy was employed to further enhance the selectivity and stability of CuMgAl-LDH, achieving a FE of 71.6 % for CO<sub>2</sub> reduction to CH<sub>4</sub>, with stability maintained for over 13 h. The results present a useful case for studying catalyst reconstruction and improving CO<sub>2</sub> reduction performance.","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"29 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142975516","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 : 2025-01-13DOI: 10.1016/j.jcat.2025.115966
Hanwen Hu, Jijie Wang, Can Li
Direct hydrogenation of CO2 into high value − added chemicals and fuels has received great attention in recent years. However, highly selective synthesis of single aromatic product by one − step CO2 hydrogenation is still a big challenge. Herein, we designed a ZnZrO/modified-ZSM-11 tandem catalyst which realized the selectivity of aromatics in liquid products up to 96 % and the selectivity of tetramethylbenzene(TeMB) in aromatics up to 83 % in the reaction of CO2 hydrogenation. We found that the organic base TBAOH is more favorable for the generation of uniform mesopores in ZSM-11 compared to TPAOH, thus increasing the selectivity of aromatics and TeMB. In addition, the secondary acid treatment mainly removes the extra − framework Al(EFAl) species produced by the alkali treatment, which significantly increases the relative amount of the strong Brønsted acid, thus facilitating further increase in the selectivity of aromatics and TeMB.
{"title":"Highly selective synthesis of tetramethylbenzene from CO2 hydrogenation over ZnZrO/modified-ZSM-11 tandem catalyst","authors":"Hanwen Hu, Jijie Wang, Can Li","doi":"10.1016/j.jcat.2025.115966","DOIUrl":"https://doi.org/10.1016/j.jcat.2025.115966","url":null,"abstract":"Direct hydrogenation of CO<sub>2</sub> into high value − added chemicals and fuels has received great attention in recent years. However, highly selective synthesis of single aromatic product by one − step CO<sub>2</sub> hydrogenation is still a big challenge. Herein, we designed a ZnZrO/modified-ZSM-11 tandem catalyst which realized the selectivity of aromatics in liquid products up to 96 % and the selectivity of tetramethylbenzene(TeMB) in aromatics up to 83 % in the reaction of CO<sub>2</sub> hydrogenation. We found that the organic base TBAOH is more favorable for the generation of uniform mesopores in ZSM-11 compared to TPAOH, thus increasing the selectivity of aromatics and TeMB. In addition, the secondary acid treatment mainly removes the extra − framework Al(EFAl) species produced by the alkali treatment, which significantly increases the relative amount of the strong Brønsted acid, thus facilitating further increase in the selectivity of aromatics and TeMB.","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"28 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142975514","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 : 2025-01-12DOI: 10.1016/j.jcat.2025.115958
Lichen Zhang, Wei Zhang, Bo Qin, Jiajun Zheng, Weijiong Dai, Tong Zhang, Yanze Du, Wenlin Li, Yan Wang, Ruifeng Li
Owing to the important industrial value in hydro-isomerization/-cracking process, metal–acid bifunctional catalysts have attracted much attention. However, exploring the spatial distance namely the intimacy between the two active components remains a primary challenge in the development of a bifunctional catalytic system, as there are limited synthesis protocols for rationally organizing the two components to maximize the synergistic effect. Herein, a series of catalysts with different degrees of intimacy were prepared, which can be assorted into four scales: atomic-, nanometer-, µm-, and millimeter-scale. Specially, Pt/Y@nS core–shell composite with an adjustable shell thickness in a nanometer scale (∼15 to ∼ 60 nm) was designed and synthesized. Not only playing a crucial role in confining and promoting highly dispersed Pt nanoparticles, the acid-free mesoporous SiO2 shell also finely regulates the distance (“L”) between acids and metals in a nanoscale, thereby facilitating a deep investigation into the spatial relationship between metals and acid sites. Three n-alkanes (n-heptane, n-dodecane, and n-hexadecane) with a different molecular chain length (“l”) were selected as probe molecules so as to investigate the effect of “L/l” ratio on the hydro-isomerization/-cracking reaction. The results indicated that a relatively small L/l (≤13.1) ratio is not in favor of the conversion of the alkane molecules, for example, the hydro-cracking/-isomerization process of n-dodecane, n-hexadecane, or n-heptane on 0.2Pt/Y, 0.2Pt/Y@0.5S. A smaller L/l ratio offers the catalyst with a low catalytic activity, here, isomerization and cracking yields are low. High selectivity towards mono-branched i-alkane accompanied with a little of cracked products with more carbon atoms can be obtained. On the contrary, a relatively large L/l (52.3 > L/l ≥ 26.5) ratio in the catalyst contributes to elevating the catalytic activity, for example, the hydro-cracking/-isomerization process of n-dodecane or n-hexadecane on catalysts 0.2Pt/Y@1.5S, n-heptane on 0.2Pt/Y@1S. A larger L/l ratio gives the catalyst a higher activity in hydrocracking, in which more cleavage products with lesser carbon atoms can be obtained, and with an enhanced L/l ratio, the selectivity towards corresponding i-alkane along with the selectivity ratio of mono-branched i-alkanes to multi-branched ones in the final products decreases significantly.
{"title":"Core-shell bifunctional catalysts: Controllable intimacy between metals and acids within nanometer-scale for n-alkane conversion","authors":"Lichen Zhang, Wei Zhang, Bo Qin, Jiajun Zheng, Weijiong Dai, Tong Zhang, Yanze Du, Wenlin Li, Yan Wang, Ruifeng Li","doi":"10.1016/j.jcat.2025.115958","DOIUrl":"https://doi.org/10.1016/j.jcat.2025.115958","url":null,"abstract":"Owing to the important industrial value in hydro-isomerization/-cracking process, metal–acid bifunctional catalysts have attracted much attention. However, exploring the spatial distance namely the intimacy between the two active components remains a primary challenge in the development of a bifunctional catalytic system, as there are limited synthesis protocols for rationally organizing the two components to maximize the synergistic effect. Herein, a series of catalysts with different degrees of intimacy were prepared, which can be assorted into four scales: atomic-, nanometer-, µm-, and millimeter-scale. Specially, Pt/Y@<em>n</em>S core–shell composite with an adjustable shell thickness in a nanometer scale (∼15 to ∼ 60 nm) was designed and synthesized. Not only playing a crucial role in confining and promoting highly dispersed Pt nanoparticles, the acid-free mesoporous SiO<sub>2</sub> shell also finely regulates the distance (“<em>L</em>”) between acids and metals in a nanoscale, thereby facilitating a deep investigation into the spatial relationship between metals and acid sites. Three <em>n</em>-alkanes (<em>n</em>-heptane, <em>n</em>-dodecane, and <em>n</em>-hexadecane) with a different molecular chain length (“<em>l</em>”) were selected as probe molecules so as to investigate the effect of “<em>L/l</em>” ratio on the hydro-isomerization/-cracking reaction. The results indicated that a relatively small <em>L</em>/<em>l</em> (≤13.1) ratio is not in favor of the conversion of the alkane molecules, for example, the hydro-cracking/-isomerization process of <em>n</em>-dodecane, <em>n</em>-hexadecane, or <em>n</em>-heptane on 0.2Pt/Y, 0.2Pt/Y@0.5S. A smaller <em>L</em>/<em>l</em> ratio offers the catalyst with a low catalytic activity, here, isomerization and cracking yields are low. High selectivity towards mono-branched <em>i</em>-alkane accompanied with a little of cracked products with more carbon atoms can be obtained. On the contrary, a relatively large <em>L</em>/<em>l</em> (52.3 > <em>L/l</em> ≥ 26.5) ratio in the catalyst contributes to elevating the catalytic activity, for example, the hydro-cracking/-isomerization process of <em>n</em>-dodecane or <em>n</em>-hexadecane on catalysts 0.2Pt/Y@1.5S, <em>n</em>-heptane on 0.2Pt/Y@1S. A larger <em>L/l</em> ratio gives the catalyst a higher activity in hydrocracking, in which more cleavage products with lesser carbon atoms can be obtained, and with an enhanced <em>L/l</em> ratio, the selectivity towards corresponding <em>i</em>-alkane along with the selectivity ratio of mono-branched <em>i</em>-alkanes to multi-branched ones in the final products decreases significantly.","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"36 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2025-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142968433","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 : 2025-01-11DOI: 10.1016/j.jcat.2025.115960
Primož Jovanovič, Armin Hrnjić, Luka Pavko, Martin Šala, Francisco-Ruiz Zepeda, Marjan Bele, Nejc Hodnik
Reliable assessment of electrocatalytic performance of novel materials to determine the oxygen reduction (ORR) activity plays a pivotal role in systematic-driven design of tailored composites. Unfortunately rotating disc electrode technique, typically employed for this purpose, is incapable to accurately predict the behaviour of promising candidates in membrane electrode assemblies (MEAs) which are finally used in fuel cells. Instead, miniature electrochemical setups based on floating electrode, which mimics MEA’s three-phase boundary active sites, has recently been recognized as an adequate diagnostics substitute. Compared to conventional RDE the working electrode operating under floating regime makes the acquisition of catalysts’ behaviour at low potentials easily achieved without being limited by the solubility and/or mass transport of O2 in aqueous electrolyte. Accordingly, the present study employs a modified version of the floating electrode methodology (MFE) to accurately investigate the effect of electrocatalyst nanostructure on high-current density ORR performance. Two morphologically distinct platinum-based de-alloyed nanoparticle samples—porous and non-porous core–shell analogues—are compared. The analysis reveals that at the high current density region (< 0.8 V vs RHE) porous nanoparticles demonstrate significantly worse ORR specific activities in comparison to core–shell analogues. On the other hand, the performance is reversed at low current densities (> 0.8 V vs RHE) supporting the results from the RDE analysis. The observed trend is attributed to a reduction in the utilization of active surface area in nanoporous catalysts with increasing overpotential.
{"title":"The role of nanoporosity in oxygen reduction reaction under elevated mass transport: Porous vs core-shell","authors":"Primož Jovanovič, Armin Hrnjić, Luka Pavko, Martin Šala, Francisco-Ruiz Zepeda, Marjan Bele, Nejc Hodnik","doi":"10.1016/j.jcat.2025.115960","DOIUrl":"https://doi.org/10.1016/j.jcat.2025.115960","url":null,"abstract":"Reliable assessment of electrocatalytic performance of novel materials to determine the oxygen reduction (ORR) activity plays a pivotal role in systematic-driven design of tailored composites. Unfortunately rotating disc electrode technique, typically employed for this purpose, is incapable to accurately predict the behaviour of promising candidates in membrane electrode assemblies (MEAs) which are finally used in fuel cells. Instead, miniature electrochemical setups based on floating electrode, which mimics MEA’s three-phase boundary active sites, has recently been recognized as an adequate diagnostics substitute. Compared to conventional RDE the working electrode operating under floating regime makes the acquisition of catalysts’ behaviour at low potentials easily achieved without being limited by the solubility and/or mass transport of O<sub>2</sub> in aqueous electrolyte. Accordingly, the present study employs a modified version of the floating electrode methodology (MFE) to accurately investigate the effect of electrocatalyst nanostructure on high-current density ORR performance. Two morphologically distinct platinum-based de-alloyed nanoparticle samples—porous and non-porous core–shell analogues—are compared. The analysis reveals that at the high current density region (< 0.8 V vs RHE) porous nanoparticles demonstrate significantly worse ORR specific activities in comparison to core–shell analogues. On the other hand, the performance is reversed at low current densities (> 0.8 V vs RHE) supporting the results from the RDE analysis. The observed trend is attributed to a reduction in the utilization of active surface area in nanoporous catalysts with increasing overpotential.","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"36 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2025-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142961697","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 : 2025-01-11DOI: 10.1016/j.jcat.2025.115964
Guang-Hui Shi, Yu-Fen Xie, Guo-Sheng Zhang, Pei-Ying Peng, Long-Gen Hu, Chen Chen, Xiao-Li Zhao, Yong Lu, Ye Liu
A series of base-built-in-PNP-ligands (L1-L4) were synthesized and fully characterized. The synthesis methodology for these ligands were simple and efficient without involvement of high-risky BuLi or high-cost transition metal catalysts. With the aid of the pyrazinyl-tertiary amine-based bis-PNP ligand of L1, in the coexistence of the nucleophiles of amine and MeOH, the terminal alkynes smoothly converted to N-substituted succinimides in moderate to excellent isolated yields, via one-pot three-step tandem reaction in aminocarbonylation-methoxycarbnylation-cyclization sequence. The developed L1-Pd(MeCN)2Cl2 catalyst exhibited typical cascade catalysis with divergent performance towards each individual reaction-step. And the second-step methoxycarbonylation of the branched α,β-unsaturated amides towards ω-amido esters was a decent detour for the successful production of N-substituted succinimides from alkynes, CO and primary amines.
{"title":"Cascade catalysis of bis-PNP-ligand-modified Pd-catalyst for three-step aminocarbonylation-methoxycarbonylation-cyclization tandem reaction for synthesis of N-substituted succinimides from terminal alkynes","authors":"Guang-Hui Shi, Yu-Fen Xie, Guo-Sheng Zhang, Pei-Ying Peng, Long-Gen Hu, Chen Chen, Xiao-Li Zhao, Yong Lu, Ye Liu","doi":"10.1016/j.jcat.2025.115964","DOIUrl":"https://doi.org/10.1016/j.jcat.2025.115964","url":null,"abstract":"A series of base-built-in-PNP-ligands (<strong>L1-L4</strong>) were synthesized and fully characterized. The synthesis methodology for these ligands were simple and efficient without involvement of high-risky BuLi or high-cost transition metal catalysts. With the aid of the pyrazinyl-tertiary amine-based bis-PNP ligand of <strong>L1</strong>, in the coexistence of the nucleophiles of amine and MeOH, the terminal alkynes smoothly converted to N-substituted succinimides in moderate to excellent isolated yields, via one-pot three-step tandem reaction in aminocarbonylation-methoxycarbnylation-cyclization sequence. The developed <strong>L1-</strong>Pd(MeCN)<sub>2</sub>Cl<sub>2</sub> catalyst exhibited typical cascade catalysis with divergent performance towards each individual reaction-step. And the second-step methoxycarbonylation of the branched <em>α,β</em>-unsaturated amides towards ω-amido esters was a decent detour for the successful production of N-substituted succinimides from alkynes, CO and primary amines.","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"26 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2025-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142962756","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 : 2025-01-11DOI: 10.1016/j.jcat.2025.115939
Ayodeji Omoniyi, Emma Nei, Samir Bensaid, Giuseppe Pipitone, Alyssa J.R. Hensley
Carboxylic acids derived from biomass can be upgraded via heterogeneous catalytic processes to replacement petrochemicals or green hydrogen. A limiting factor in the catalytic upgrading of biomass-derived carboxylic acids is the varied composition of reactant mixtures and consequential competitive adsorption effects between acids that ultimately control reactivity. To address this limitation, the combined effects of intermolecular interactions and acid molecular structure on the dominant adsorbed acid configurations at catalytically relevant coverages must be explored. Here, we determine the coverage- and configuration-dependent adsorption behavior of seven carboxylic acids on Pt(111) using density functional theory and ab initio molecular dynamics simulations. The carboxylic acids—ranging from formic to lactic acid—were chosen to vary carbon chain length and terminal end substituents. The results show that at moderate to high coverages, carboxylic acids preferentially form dimers on Pt(111), regardless of the individual acid’s molecular structure. This is due to strongly attractive intermolecular interactions through hydrogen bonding between neighboring R-COOH substituents. Dimer stability was further influenced by carbon chain length and the number and chain placement of R-OH substituents. Finally, the observed trends in adsorption energy with acid molecular structure were used to develop and validate a general additivity model for predicting the adsorption energies of carboxylic acid dimers on Pt(111). This additivity model sheds light on the relative contributions of various substituents to adsorption strength: –COOH > –OH > –CH3. Overall, this work elucidates the important role of intermolecular interactions in the coverage- and configuration-dependent adsorption of carboxylic acids on transition metal surfaces. Furthermore, we provide a predictive tool for easily and rapidly rationalizing competitive adsorption effects during the catalytic upgrading of multi-component carboxylic acid mixtures.
{"title":"Role of intermolecular interactions in the Coverage- and configuration-dependent adsorption of carboxylic acids on Pt(111)","authors":"Ayodeji Omoniyi, Emma Nei, Samir Bensaid, Giuseppe Pipitone, Alyssa J.R. Hensley","doi":"10.1016/j.jcat.2025.115939","DOIUrl":"https://doi.org/10.1016/j.jcat.2025.115939","url":null,"abstract":"Carboxylic acids derived from biomass can be upgraded via heterogeneous catalytic processes to replacement petrochemicals or green hydrogen. A limiting factor in the catalytic upgrading of biomass-derived carboxylic acids is the varied composition of reactant mixtures and consequential competitive adsorption effects between acids that ultimately control reactivity. To address this limitation, the combined effects of intermolecular interactions and acid molecular structure on the dominant adsorbed acid configurations at catalytically relevant coverages must be explored. Here, we determine the coverage- and configuration-dependent adsorption behavior of seven carboxylic acids on Pt(111) using density functional theory and <em>ab initio</em> molecular dynamics simulations. The carboxylic acids—ranging from formic to lactic acid—were chosen to vary carbon chain length and terminal end substituents. The results show that at moderate to high coverages, carboxylic acids preferentially form dimers on Pt(111), regardless of the individual acid’s molecular structure. This is due to strongly attractive intermolecular interactions through hydrogen bonding between neighboring R-COOH substituents. Dimer stability was further influenced by carbon chain length and the number and chain placement of R-OH substituents. Finally, the observed trends in adsorption energy with acid molecular structure were used to develop and validate a general additivity model for predicting the adsorption energies of carboxylic acid dimers on Pt(111). This additivity model sheds light on the relative contributions of various substituents to adsorption strength: –COOH > –OH > –CH<sub>3</sub>. Overall, this work elucidates the important role of intermolecular interactions in the coverage- and configuration-dependent adsorption of carboxylic acids on transition metal surfaces. Furthermore, we provide a predictive tool for easily and rapidly rationalizing competitive adsorption effects during the catalytic upgrading of multi-component carboxylic acid mixtures.","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"82 1","pages":""},"PeriodicalIF":7.3,"publicationDate":"2025-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142961698","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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