Exploring visible-light-responsive photocatalysts for photocatalytic lignocellulosic biomass-to-H2 conversion remains a glamorous but challenging goal because the photogenerated holes cannot directly transfer to biomass owing to the absence of a charge transfer channel. Herein, we design ZnIn2S4 nanosheets with abundant sulfur vacancy (VS-ZnIn2S4) as visible light responsive photocatalysts for photocatalytic H2 production from lignocellulosic biomass in the presence of MoS2 as the cocatalyst. In this smartly designed photocatalysts, the sulfur vacancy in ZnIn2S4 reduces the energy barrier of •OH generation reaction and results in the fast dynamics for the generation of •OH, which acts as the crucial species for the oxygenolysis of lignocellulosic biomass. As expected, the H2 generation rate of the optimized MoS2/VS-ZnIn2S4 photocatalyst in α-cellulose and bamboo powder aqueous solution achieves 1572 and 133 μmol·g–1·h–1, respectively. This study validates the feasibility of sulfur vacancy to boost visible light photocatalytic conversion of lignocellulosic biomass into H2 fuel.
{"title":"Sustainable H2 Production from Lignocellulosic Biomass over MoS2 Modified Sulfur Vacancy Enriched ZnIn2S4 Photocatalyst","authors":"Ji-Ping Tang, Yan Chen, Zi-Yi Wang, Yun-Hui Hu, Jia-Hao Wang, Liang Bao, Zong-Yan Zhao, Yong-Jun Yuan","doi":"10.1021/acscatal.4c05707","DOIUrl":"https://doi.org/10.1021/acscatal.4c05707","url":null,"abstract":"Exploring visible-light-responsive photocatalysts for photocatalytic lignocellulosic biomass-to-H<sub>2</sub> conversion remains a glamorous but challenging goal because the photogenerated holes cannot directly transfer to biomass owing to the absence of a charge transfer channel. Herein, we design ZnIn<sub>2</sub>S<sub>4</sub> nanosheets with abundant sulfur vacancy (V<sub>S</sub>-ZnIn<sub>2</sub>S<sub>4</sub>) as visible light responsive photocatalysts for photocatalytic H<sub>2</sub> production from lignocellulosic biomass in the presence of MoS<sub>2</sub> as the cocatalyst. In this smartly designed photocatalysts, the sulfur vacancy in ZnIn<sub>2</sub>S<sub>4</sub> reduces the energy barrier of <sup>•</sup>OH generation reaction and results in the fast dynamics for the generation of <sup>•</sup>OH, which acts as the crucial species for the oxygenolysis of lignocellulosic biomass. As expected, the H<sub>2</sub> generation rate of the optimized MoS<sub>2</sub>/V<sub>S</sub>-ZnIn<sub>2</sub>S<sub>4</sub> photocatalyst in α-cellulose and bamboo powder aqueous solution achieves 1572 and 133 μmol·g<sup>–1</sup>·h<sup>–1</sup>, respectively. This study validates the feasibility of sulfur vacancy to boost visible light photocatalytic conversion of lignocellulosic biomass into H<sub>2</sub> fuel.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"26 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2024-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142832585","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 : 2024-12-16DOI: 10.1021/acscatal.4c05918
Andrés García-Viada, Emma Duro, Celia Sánchez-González, Inés Alonso, Nuria Rodríguez, Javier Adrio, Juan C. Carretero
We herein describe the high-valent cobalt-catalyzed C(sp3)–H functionalization of amide derivatives with silver acetylides generated in situ. The reaction proceeds under kinetic control at 60 °C, with a catalyst loading of 5 mol %. These extraordinarily mild conditions for Co-catalysis enable the synthesis of 5-(Z)-ethylidene pyrrolidin-2-one derivatives in good yield and selectivity. Density functional theory calculations have revealed a unique mechanism involving Co–Ag bimetallic species, rationalizing the nature of the catalytically active species and the role of each additive.
{"title":"Ag/Co-Bimetallic Cooperation in the C–H Functionalization of Aliphatic Amides with Propiolic Acids","authors":"Andrés García-Viada, Emma Duro, Celia Sánchez-González, Inés Alonso, Nuria Rodríguez, Javier Adrio, Juan C. Carretero","doi":"10.1021/acscatal.4c05918","DOIUrl":"https://doi.org/10.1021/acscatal.4c05918","url":null,"abstract":"We herein describe the high-valent cobalt-catalyzed C(sp<sup>3</sup>)–H functionalization of amide derivatives with silver acetylides generated in situ. The reaction proceeds under kinetic control at 60 °C, with a catalyst loading of 5 mol %. These extraordinarily mild conditions for Co-catalysis enable the synthesis of 5-(<i>Z</i>)-ethylidene pyrrolidin-2-one derivatives in good yield and selectivity. Density functional theory calculations have revealed a unique mechanism involving Co–Ag bimetallic species, rationalizing the nature of the catalytically active species and the role of each additive.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"14 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142825608","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 : 2024-12-16DOI: 10.1021/acscatal.4c04935
Ewald P. J. Jongkind, Jack Domenech, Arthur Govers, Marcel van den Broek, Jean-Marc Daran, Gideon Grogan, Caroline E. Paul
Reductive amination is one of the most synthetically direct routes to access chiral amines. Several Imine Reductases (IREDs) have been discovered to catalyze reductive amination (Reductive Aminases or RedAms), yet they are dependent on the expensive phosphorylated nicotinamide adenine dinucleotide cofactor NADPH and usually more active at basic pH. Here, we describe the discovery and synthetic potential of an IRED from Rhodococcus erythropolis (RytRedAm) that catalyzes reductive amination between a series of medium to large carbonyl and amine compounds with conversions of up to >99% and 99% enantiomeric excess at neutral pH. RytRedAm catalyzes the formation of a substituted γ-lactam and N-methyl-1-phenylethanamine with stereochemistry opposite to that of fungal RedAms, giving the (S)-enantiomer. This enzyme remarkably uses both NADPH and NADH cofactors with KM values of 15 and 247 μM and turnover numbers kcat of 3.6 and 9.0 s–1, respectively, for the reductive amination of hexanal with allylamine. The crystal structure obtained provides insights into the flexibility to also accept NADH, with residues R35 and I69 diverging from that of other IREDs/RedAms in the otherwise conserved Rossmann fold. RytRedAm thus represents a subfamily of enzymes that enable synthetic applications using NADH-dependent reductive amination to access complementary chiral amine products.
{"title":"Discovery and Synthetic Applications of a NAD(P)H-Dependent Reductive Aminase from Rhodococcus erythropolis","authors":"Ewald P. J. Jongkind, Jack Domenech, Arthur Govers, Marcel van den Broek, Jean-Marc Daran, Gideon Grogan, Caroline E. Paul","doi":"10.1021/acscatal.4c04935","DOIUrl":"https://doi.org/10.1021/acscatal.4c04935","url":null,"abstract":"Reductive amination is one of the most synthetically direct routes to access chiral amines. Several Imine Reductases (IREDs) have been discovered to catalyze reductive amination (Reductive Aminases or RedAms), yet they are dependent on the expensive phosphorylated nicotinamide adenine dinucleotide cofactor NADPH and usually more active at basic pH. Here, we describe the discovery and synthetic potential of an IRED from <i>Rhodococcus erythropolis</i> (<i>Ryt</i>RedAm) that catalyzes reductive amination between a series of medium to large carbonyl and amine compounds with conversions of up to >99% and 99% enantiomeric excess at neutral pH. <i>Ryt</i>RedAm catalyzes the formation of a substituted γ-lactam and <i>N</i>-methyl-1-phenylethanamine with stereochemistry opposite to that of fungal RedAms, giving the (<i>S</i>)-enantiomer. This enzyme remarkably uses both NADPH and NADH cofactors with <i>K</i><sub>M</sub> values of 15 and 247 μM and turnover numbers <i>k</i><sub>cat</sub> of 3.6 and 9.0 s<sup>–1</sup>, respectively, for the reductive amination of hexanal with allylamine. The crystal structure obtained provides insights into the flexibility to also accept NADH, with residues R35 and I69 diverging from that of other IREDs/RedAms in the otherwise conserved Rossmann fold. <i>Ryt</i>RedAm thus represents a subfamily of enzymes that enable synthetic applications using NADH-dependent reductive amination to access complementary chiral amine products.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"52 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142832587","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 : 2024-12-16DOI: 10.1021/acscatal.4c04257
Ben Ashley, Chiara Demingo, Henriette Rozeboom, Niccoló Bianciardi, Tomás Dunleavy, Jacob-Jan Haaksma, Yiming Guo, Marco W. Fraaije
Aryl ethers are ubiquitous protecting groups of alcohols and amines in organic chemistry. This is owed to the simplicity of their appendage to molecules and the robust protection afforded. However, aryl ethers and amines can be challenging to cleave, often requiring harsh and unselective reductive conditions. We report the structure-based engineering of a promiscuous, ether-cleaving vanillyl alcohol oxidase-type biocatalyst for activity on a wide range of para-hydroxy benzyl ethers. Two superior quadruple mutants are identified with improved kinetics and substrate scope. One evolved variant and two predecessors are crystallized, and their structures resolved to 2.8–1.5 Å, revealing a significant increase in the volume and flexibility of the active site cavity. To illustrate the potential usefulness of the engineered biocatalysts, one is later coupled with another biocatalyst in a cascade reaction to catalyze the selective cleavage of an uncommon aryl ether protecting group, para-acyloxy benzyl ethers, in good yield and under mild conditions.
{"title":"Biocatalytic Cleavage of para-Acetoxy Benzyl Ethers: Application to Protecting Group Chemistry","authors":"Ben Ashley, Chiara Demingo, Henriette Rozeboom, Niccoló Bianciardi, Tomás Dunleavy, Jacob-Jan Haaksma, Yiming Guo, Marco W. Fraaije","doi":"10.1021/acscatal.4c04257","DOIUrl":"https://doi.org/10.1021/acscatal.4c04257","url":null,"abstract":"Aryl ethers are ubiquitous protecting groups of alcohols and amines in organic chemistry. This is owed to the simplicity of their appendage to molecules and the robust protection afforded. However, aryl ethers and amines can be challenging to cleave, often requiring harsh and unselective reductive conditions. We report the structure-based engineering of a promiscuous, ether-cleaving vanillyl alcohol oxidase-type biocatalyst for activity on a wide range of <i>para</i>-hydroxy benzyl ethers. Two superior quadruple mutants are identified with improved kinetics and substrate scope. One evolved variant and two predecessors are crystallized, and their structures resolved to 2.8–1.5 Å, revealing a significant increase in the volume and flexibility of the active site cavity. To illustrate the potential usefulness of the engineered biocatalysts, one is later coupled with another biocatalyst in a cascade reaction to catalyze the selective cleavage of an uncommon aryl ether protecting group, <i>para</i>-acyloxy benzyl ethers, in good yield and under mild conditions.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"46 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142825753","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 : 2024-12-16DOI: 10.1021/acscatal.4c05269
Xianxian Xie, Valentín Briega-Martos, Pere Alemany, Athira Lekshmi Mohandas Sandhya, Tomáš Skála, Miquel Gamón Rodríguez, Jaroslava Nováková, Milan Dopita, Michael Vorochta, Albert Bruix, Serhiy Cherevko, Konstantin M. Neyman, Iva Matolínová, Ivan Khalakhan
Achieving the optimal balance between cost-efficiency and stability of oxygen reduction reaction (ORR) catalysts is currently among the key research focuses aiming at reaching a broader implementation of proton-exchange membrane fuel cells (PEMFCs). To address this challenge, we combine two well-established strategies to enhance both activity and stability of platinum-based ORR catalysts. Specifically, we prepare ternary PtNi–Au alloys, where each alloying element plays a distinct role: Ni reduces costs and boosts ORR activity, while Au enhances stability. A systematic comparative analysis of the activity–stability relationship for compositionally tuned PtNi–Au model layers, prepared by magnetron co-sputtering, was conducted using a diverse range of complementary characterization techniques and electrochemistry, supported by density functional theory calculations. Our study reveals that a progressive increase of the Au concentration in the Pt50Ni50 alloy from 3 to 15 at % leads to opposing catalyst activity and stability trends. Specifically, we observe a decrease in the ORR activity accompanied by an increase in catalyst stability, manifested in the suppression of both Pt and Ni dissolution. Despite the reduced activity compared to PtNi, the PtNi–Au alloy with 15 at % Au still exhibits nearly three times the activity of monometallic Pt. It also demonstrates a significantly improved dissolution stability relative to that of the PtNi alloy and even monometallic Pt. These findings provide valuable insights into the intricate balance between activity and stability in multimetallic ORR catalysts, paving the way for the design of cost-effective and durable materials for PEMFCs.
{"title":"Balancing Activity and Stability through Compositional Engineering of Ternary PtNi–Au Alloy ORR Catalysts","authors":"Xianxian Xie, Valentín Briega-Martos, Pere Alemany, Athira Lekshmi Mohandas Sandhya, Tomáš Skála, Miquel Gamón Rodríguez, Jaroslava Nováková, Milan Dopita, Michael Vorochta, Albert Bruix, Serhiy Cherevko, Konstantin M. Neyman, Iva Matolínová, Ivan Khalakhan","doi":"10.1021/acscatal.4c05269","DOIUrl":"https://doi.org/10.1021/acscatal.4c05269","url":null,"abstract":"Achieving the optimal balance between cost-efficiency and stability of oxygen reduction reaction (ORR) catalysts is currently among the key research focuses aiming at reaching a broader implementation of proton-exchange membrane fuel cells (PEMFCs). To address this challenge, we combine two well-established strategies to enhance both activity and stability of platinum-based ORR catalysts. Specifically, we prepare ternary PtNi–Au alloys, where each alloying element plays a distinct role: Ni reduces costs and boosts ORR activity, while Au enhances stability. A systematic comparative analysis of the activity–stability relationship for compositionally tuned PtNi–Au model layers, prepared by magnetron co-sputtering, was conducted using a diverse range of complementary characterization techniques and electrochemistry, supported by density functional theory calculations. Our study reveals that a progressive increase of the Au concentration in the Pt<sub>50</sub>Ni<sub>50</sub> alloy from 3 to 15 at % leads to opposing catalyst activity and stability trends. Specifically, we observe a decrease in the ORR activity accompanied by an increase in catalyst stability, manifested in the suppression of both Pt and Ni dissolution. Despite the reduced activity compared to PtNi, the PtNi–Au alloy with 15 at % Au still exhibits nearly three times the activity of monometallic Pt. It also demonstrates a significantly improved dissolution stability relative to that of the PtNi alloy and even monometallic Pt. These findings provide valuable insights into the intricate balance between activity and stability in multimetallic ORR catalysts, paving the way for the design of cost-effective and durable materials for PEMFCs.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"12 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142832588","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 : 2024-12-16DOI: 10.1021/acscatal.4c05857
Jaeyoung Yoo, Jungwoo Choi, Suyeon Choi, Changsoo Lee, Hyuck Mo Lee
Ammonia (NH3) is emerging as a promising carbon-free chemical energy source, offering higher storage capacity per unit volume compared to hydrogen and enhanced ease of liquefaction. This makes NH3 suitable for long-distance transportation and various industrial applications. The ammonia oxidation reaction (AOR) is crucial for electrochemically converting NH3 into H2, but current AOR catalysts face commercialization challenges due to cost and efficiency issues. This study explores ways to enhance AOR catalysts through a combined theoretical and experimental approach, focusing on Pt3X (where X represents screening elements) alloys. Density functional theory calculations were employed to analyze the AOR mechanism on Pt(111), (110), and (100) surfaces, identifying descriptors that facilitated the high-throughput screening of Pt3X alloys with (111), (110), and (100) facets for the highest AOR activity. The selected Pt3M (M = Fe, Co, and Ni) alloys were synthesized and characterized, revealing well-defined cubic shapes and superior AOR properties compared to pure Pt. Experimental results confirmed that Pt3Fe and Pt3Co nanocubes exhibit enhanced AOR activity and stability, aligning with theoretical predictions. This integrated approach highlights the potential of Pt3M alloys as cost-effective and efficient AOR catalysts, advancing ammonia electrolysis technologies for hydrogen production.
{"title":"Facet-Controlled Pt3M Alloys as Enhanced Catalysts for Ammonia Oxidation Reaction: A Combined Theoretical and Experimental Study","authors":"Jaeyoung Yoo, Jungwoo Choi, Suyeon Choi, Changsoo Lee, Hyuck Mo Lee","doi":"10.1021/acscatal.4c05857","DOIUrl":"https://doi.org/10.1021/acscatal.4c05857","url":null,"abstract":"Ammonia (NH<sub>3</sub>) is emerging as a promising carbon-free chemical energy source, offering higher storage capacity per unit volume compared to hydrogen and enhanced ease of liquefaction. This makes NH<sub>3</sub> suitable for long-distance transportation and various industrial applications. The ammonia oxidation reaction (AOR) is crucial for electrochemically converting NH<sub>3</sub> into H<sub>2</sub>, but current AOR catalysts face commercialization challenges due to cost and efficiency issues. This study explores ways to enhance AOR catalysts through a combined theoretical and experimental approach, focusing on Pt<sub>3</sub>X (where X represents screening elements) alloys. Density functional theory calculations were employed to analyze the AOR mechanism on Pt(111), (110), and (100) surfaces, identifying descriptors that facilitated the high-throughput screening of Pt<sub>3</sub>X alloys with (111), (110), and (100) facets for the highest AOR activity. The selected Pt<sub>3</sub>M (M = Fe, Co, and Ni) alloys were synthesized and characterized, revealing well-defined cubic shapes and superior AOR properties compared to pure Pt. Experimental results confirmed that Pt<sub>3</sub>Fe and Pt<sub>3</sub>Co nanocubes exhibit enhanced AOR activity and stability, aligning with theoretical predictions. This integrated approach highlights the potential of Pt<sub>3</sub>M alloys as cost-effective and efficient AOR catalysts, advancing ammonia electrolysis technologies for hydrogen production.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"22 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142825757","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}
The rational design of highly efficient Co–Fe bimetallic catalysts is highly desirable for CO2 hydrogenation to olefins as an important alternative for traditional petroleum cracking technology. The treatment of carburization to construct the active phases stands out. Herein, the composition of active CoFe alloy carbide catalysts consisting of χ-(CoxFe1–x)5C2 and θ-(CoxFe1–x)3C phases was fine-tuned by altering the carburization environment. The synergistic effect between the dual components was optimized to improve the CO2 activation and C–C coupling capacity. The appropriate carburization degree and phase composition of CoFe alloy carbides are favorable for enhancing the space-time yield (STY) of C2+ olefins, up to 328.1 mg gcat–1 h–1 on the CoFe catalyst carburized in H2/CO = 2 at 320 °C for 8 h. This work provides useful guidelines for regulating product distribution in the design and synthesis of highly efficient catalysts.
{"title":"Fine-Tuning the Active Phases of CoFe Alloy Carbides for Boosting Olefin Synthesis from CO2 Hydrogenation","authors":"Na Liu, Qixin Fan, Jian Wei, Guanghui Zhang, Jian Sun, Wenhui Li, Chunshan Song, Xinwen Guo","doi":"10.1021/acscatal.4c06112","DOIUrl":"https://doi.org/10.1021/acscatal.4c06112","url":null,"abstract":"The rational design of highly efficient Co–Fe bimetallic catalysts is highly desirable for CO<sub>2</sub> hydrogenation to olefins as an important alternative for traditional petroleum cracking technology. The treatment of carburization to construct the active phases stands out. Herein, the composition of active CoFe alloy carbide catalysts consisting of χ-(Co<sub><i>x</i></sub>Fe<sub>1–<i>x</i></sub>)<sub>5</sub>C<sub>2</sub> and θ-(Co<sub><i>x</i></sub>Fe<sub>1–<i>x</i></sub>)<sub>3</sub>C phases was fine-tuned by altering the carburization environment. The synergistic effect between the dual components was optimized to improve the CO<sub>2</sub> activation and C–C coupling capacity. The appropriate carburization degree and phase composition of CoFe alloy carbides are favorable for enhancing the space-time yield (STY) of C<sub>2+</sub> olefins, up to 328.1 mg g<sub>cat</sub><sup>–1</sup> h<sup>–1</sup> on the CoFe catalyst carburized in H<sub>2</sub>/CO = 2 at 320 °C for 8 h. This work provides useful guidelines for regulating product distribution in the design and synthesis of highly efficient catalysts.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"16 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142825610","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 : 2024-12-16DOI: 10.1021/acscatal.4c05744
Hengyu Li, Yangfan Shao, Zhichao Zhang, Muhammad N. Tahir, Tingzheng Hou, Lin Gan, Feng Ding, Jia Li
Metal–nitrogen–carbon (M–N–C) single-atom catalysts (SACs) have emerged as promising heterogeneous electrocatalysts for the CO2 reduction reaction (CO2RR). However, the predominant production of CO over multielectron products remains a challenge for most M–N–C SACs, with the exception of cobalt phthalocyanine (CoPc). In this study, the comparison of CoPc and a series of analogous M–N–C SACs was systematically investigated using density functional theory calculations to unravel the factors contributing to the selectivity of CoPc in catalyzing multielectron CO2RR. The relationship between the selectivity and the electronic configuration of M–N–C SACs was revealed. The half-filled dz2 orbital of the cobalt ion lead to moderate chemisorption of *CO on CoPc, enabling the subsequent protonation of *CO. In addition, we identified a unique type of hydrogen bond in which the C atom of *CO acts as the proton acceptor (C···H–O hydrogen bond), which significantly promotes the proton transfer to *CO and selectivity for multielectron products. Only the *CO on CoPc was observed to form the C···H–O hydrogen bond, elucidating the unique multielectron CO2RR performance of CoPc. In addition, we further elucidated the formation mechanism of the C···H–O hydrogen bond, which provides an alternative strategy to accelerate proton transfer in electrochemical reactions by utilizing this unconventional hydrogen bond.
{"title":"Understanding the Unique Selectivity of Cobalt Phthalocyanine in Multielectron Reduction of Carbon Dioxide","authors":"Hengyu Li, Yangfan Shao, Zhichao Zhang, Muhammad N. Tahir, Tingzheng Hou, Lin Gan, Feng Ding, Jia Li","doi":"10.1021/acscatal.4c05744","DOIUrl":"https://doi.org/10.1021/acscatal.4c05744","url":null,"abstract":"Metal–nitrogen–carbon (M–N–C) single-atom catalysts (SACs) have emerged as promising heterogeneous electrocatalysts for the CO<sub>2</sub> reduction reaction (CO<sub>2</sub>RR). However, the predominant production of CO over multielectron products remains a challenge for most M–N–C SACs, with the exception of cobalt phthalocyanine (CoPc). In this study, the comparison of CoPc and a series of analogous M–N–C SACs was systematically investigated using density functional theory calculations to unravel the factors contributing to the selectivity of CoPc in catalyzing multielectron CO<sub>2</sub>RR. The relationship between the selectivity and the electronic configuration of M–N–C SACs was revealed. The half-filled d<sub><i>z</i><sup>2</sup></sub> orbital of the cobalt ion lead to moderate chemisorption of *CO on CoPc, enabling the subsequent protonation of *CO. In addition, we identified a unique type of hydrogen bond in which the C atom of *CO acts as the proton acceptor (C···H–O hydrogen bond), which significantly promotes the proton transfer to *CO and selectivity for multielectron products. Only the *CO on CoPc was observed to form the C···H–O hydrogen bond, elucidating the unique multielectron CO<sub>2</sub>RR performance of CoPc. In addition, we further elucidated the formation mechanism of the C···H–O hydrogen bond, which provides an alternative strategy to accelerate proton transfer in electrochemical reactions by utilizing this unconventional hydrogen bond.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"39 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142825607","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 : 2024-12-16DOI: 10.1021/acscatal.4c05954
Jiajia Wang, Zhuodong Ou, Chengbo Dong, Mengying Su, Amjad Ali, Artem V. Kuklin, Hans Ågren, Glib V. Baryshnikov, Yang Liu, Xue Zhao, Haibo Zhang
Electrocatalytic nitrate reduction for ammonia (eNIRR) is an ammonia production process that simultaneously removes nitrate contaminants from water. However, the lack of activity of cathode catalysts used as eNIRR catalysts is the main limiting factor for its development. Motivated by this fact, born-doped copper (BDCu) was obtained by using ZnO, which was easily removed at high temperature, as a dispersant, combined with weakly reducing boron clusters (closo-[B12H12]2–) as a reducing agent and B source during high-temperature pyrolysis. Impressively, BDCu demonstrated a Faradaic efficiency of 96.58% and a yield rate of 25741.51 μg h–1 mgcat–1 toward ammonia production at −1.8 V (vs saturated calomel electrode). The ammonia yield rate of BDCu was twice as high as in the case of undoped B. Evolutionary behavior of NO3– to NH3 conversion detected by in situ Fourier-transform infrared (in situ FT-IR) and electrochemical in situ mass spectrometry (in situ DEMS). Experimental and density functional theory (DFT) calculations explained that the activation of water was enhanced by B-doped Cu, and the adsorption of proton *H was weakened, which made it easy for *H to migrate away from the catalyst to NO3– as a proton required for NO3– reduction. In addition, the electron-deficient of B provides conditions for electron transfer between B and Cu. The electron transfer from Cu to B in BDCu led to a decrease in the center of the d-band of Cu, which modulated the electronic properties of Cu and altered the behavior of the NO3– to NH3 transition on the Cu surface. Compared with Cu undoped B as well as unreduced CuO, BDCu lowered the energy barrier of the rate-determining step (*NO → *N), allowing for a smoother conversion of NO3– to NH3. This study provides a strategy to change the electronic structure of transition metals by B-modification and thus improve the performance of ammonia synthesis.
电催化硝酸盐还原法制氨（eNIRR）是一种同时去除水中硝酸盐污染物的制氨工艺。然而，用作 eNIRR 催化剂的阴极催化剂缺乏活性是限制其发展的主要因素。受这一事实的启发，在高温热解过程中，使用在高温下易于去除的氧化锌作为分散剂，结合弱还原性硼团簇（closo-[B12H12]2-）作为还原剂和硼源，获得了天生掺杂铜（BDCu）。令人印象深刻的是，BDCu 的法拉第效率高达 96.58%，在 -1.8 V（相对于饱和甘汞电极）电压下的氨生产产率为 25741.51 μg h-1 mgcat-1。通过原位傅立叶变换红外光谱（in situ FT-IR）和电化学原位质谱法（in situ DEMS）检测了 NO3- 向 NH3 转化的演化过程。实验和密度泛函理论（DFT）计算表明，掺杂 B 的 Cu 增强了水的活化，减弱了质子 *H 的吸附，使 *H 易于从催化剂迁移到 NO3-，成为 NO3-还原所需的质子。此外，B 的缺电子特性也为 B 和 Cu 之间的电子转移提供了条件。BDCu 中从 Cu 到 B 的电子转移导致 Cu 的 d 带中心下降，从而调节了 Cu 的电子特性，改变了 Cu 表面 NO3- 到 NH3 转变的行为。与未掺杂 B 的 Cu 以及未还原的 CuO 相比，BDCu 降低了决定速率步骤（*NO → *N）的能障，从而使 NO3- 向 NH3 的转化更加平稳。这项研究为通过 B 修饰改变过渡金属的电子结构，从而改善氨合成的性能提供了一种策略。
{"title":"Electronic Structure Modulated by B-Doped Cu Promotes Electrocatalytic Nitrate Reduction for Ammonia Production","authors":"Jiajia Wang, Zhuodong Ou, Chengbo Dong, Mengying Su, Amjad Ali, Artem V. Kuklin, Hans Ågren, Glib V. Baryshnikov, Yang Liu, Xue Zhao, Haibo Zhang","doi":"10.1021/acscatal.4c05954","DOIUrl":"https://doi.org/10.1021/acscatal.4c05954","url":null,"abstract":"Electrocatalytic nitrate reduction for ammonia (eNIRR) is an ammonia production process that simultaneously removes nitrate contaminants from water. However, the lack of activity of cathode catalysts used as eNIRR catalysts is the main limiting factor for its development. Motivated by this fact, born-doped copper (BDCu) was obtained by using ZnO, which was easily removed at high temperature, as a dispersant, combined with weakly reducing boron clusters (<i>closo</i>-[B<sub>12</sub>H<sub>12</sub>]<sup>2–</sup>) as a reducing agent and B source during high-temperature pyrolysis. Impressively, BDCu demonstrated a Faradaic efficiency of 96.58% and a yield rate of 25741.51 μg h<sup>–1</sup> mg<sub>cat</sub><sup>–1</sup> toward ammonia production at −1.8 V (vs saturated calomel electrode). The ammonia yield rate of BDCu was twice as high as in the case of undoped B. Evolutionary behavior of NO<sub>3</sub><sup>–</sup> to NH<sub>3</sub> conversion detected by in situ Fourier-transform infrared (in situ FT-IR) and electrochemical in situ mass spectrometry (in situ DEMS). Experimental and density functional theory (DFT) calculations explained that the activation of water was enhanced by B-doped Cu, and the adsorption of proton *H was weakened, which made it easy for *H to migrate away from the catalyst to NO<sub>3</sub><sup>–</sup> as a proton required for NO<sub>3</sub><sup>–</sup> reduction. In addition, the electron-deficient of B provides conditions for electron transfer between B and Cu. The electron transfer from Cu to B in BDCu led to a decrease in the center of the d-band of Cu, which modulated the electronic properties of Cu and altered the behavior of the NO<sub>3</sub><sup>–</sup> to NH<sub>3</sub> transition on the Cu surface. Compared with Cu undoped B as well as unreduced CuO, BDCu lowered the energy barrier of the rate-determining step (*NO → *N), allowing for a smoother conversion of NO<sub>3</sub><sup>–</sup> to NH<sub>3</sub>. This study provides a strategy to change the electronic structure of transition metals by B-modification and thus improve the performance of ammonia synthesis.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"34 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142825609","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 : 2024-12-16DOI: 10.1021/acscatal.4c05763
Mingjun Lv, Xinhui Yu, Jitian Liu, Xiaoxun Li
The catalytic asymmetric synthesis of functionalized C2-quaternary indoline scaffolds has garnered significant attention in organic synthesis and drug discovery due to the inherent challenges and potential applications. Herein, we present a facile approach utilizing a Pd-catalyzed intramolecular decarboxylative asymmetric amination of vinyl benzoxazepinones, leading to the efficient construction of challenging chiral 2-vinyl-2-aryl/alkyl indoline frameworks in good yields with high enantioselectivities (>50 examples, up to 83% yield and 97% ee). Furthermore, these chiral indolines can be readily scaled up and further modified to access complex polycyclic indoline structures. We also synthesized several indoline-based ligands that exhibit promising efficiency as chiral catalysts in asymmetric reactions. Computational studies provided insight into the inner-sphere asymmetric amination mechanism.
{"title":"Construction of Chiral C2-Quaternary Indolines via Palladium-Catalyzed Decarboxylative Asymmetric Amination","authors":"Mingjun Lv, Xinhui Yu, Jitian Liu, Xiaoxun Li","doi":"10.1021/acscatal.4c05763","DOIUrl":"https://doi.org/10.1021/acscatal.4c05763","url":null,"abstract":"The catalytic asymmetric synthesis of functionalized C2-quaternary indoline scaffolds has garnered significant attention in organic synthesis and drug discovery due to the inherent challenges and potential applications. Herein, we present a facile approach utilizing a Pd-catalyzed intramolecular decarboxylative asymmetric amination of vinyl benzoxazepinones, leading to the efficient construction of challenging chiral 2-vinyl-2-aryl/alkyl indoline frameworks in good yields with high enantioselectivities (>50 examples, up to 83% yield and 97% ee). Furthermore, these chiral indolines can be readily scaled up and further modified to access complex polycyclic indoline structures. We also synthesized several indoline-based ligands that exhibit promising efficiency as chiral catalysts in asymmetric reactions. Computational studies provided insight into the inner-sphere asymmetric amination mechanism.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"35 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142832606","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：