Molecular Catalysis最新文献

{"title":"Copper single atoms decorated iridium nanoparticles for the selective hydrogenation of bromonitrobenzene","authors":"Zhifeng Yu ,&nbsp;Chenqi Zhao ,&nbsp;Zhelun Xiong ,&nbsp;Zicheng Xiao ,&nbsp;Meng He ,&nbsp;Yining Wu ,&nbsp;Yu Wang ,&nbsp;Pingfan Wu ,&nbsp;Wei Guo ,&nbsp;Ning Zhang ,&nbsp;Minghui Liang","doi":"10.1016/j.mcat.2024.114631","DOIUrl":"10.1016/j.mcat.2024.114631","url":null,"abstract":"<div><div>The interaction between metals is an important factor to modify the catalytic roles of metallic catalysts, and it is highly desirable to reveal the relationship between metal-metal interaction and catalytic performance. Three types of Ir-Cu catalysts including Cu single atoms modified Ir nanoparticles and Ir-Cu alloy catalysts are prepared to observe the modifying role of Cu on Ir. Under relatively high temperature treatment, Ir-Cu alloy can be produced from Cu single atoms and Ir nanoparticles. The selectivity to bromoaniline (BAN) over Cu/C-Ir catalyst can be up to 99.9 % at the 100 % conversion of bromonitrobenzene (BNB), which is higher than that over Ir/C (94.3 %) and Ir-Cu/C alloy catalyst (98.5 %). The turnover frequencies (TOFs) of Cu/C-Ir catalysts are evidently lower than that of the Ir-Cu/C alloy catalyst, though their dispersions are higher than that of Ir-Cu/C alloy catalyst. The electronic transfer from Cu single atoms to Ir nanoparticles not only weakens the hydrogen adsorption ability but reduces the number of active sites available for splitting hydrogen molecules into hydrogen atoms, leading to a decrease in the catalytic activity for the selective hydrogenation of BNB. The interaction exerted by unalloyed Cu single atoms on Ir nanoparticles differs from that of alloyed Cu on Ir, which may be the possible reason for the different catalytic performance between Cu single atoms modified Ir nanoparticles and Ir-Cu alloy.</div></div>","PeriodicalId":393,"journal":{"name":"Molecular Catalysis","volume":"569 ","pages":"Article 114631"},"PeriodicalIF":3.9,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A superior Mn5CeTi5Ox catalysts for synergistic catalytic removal of chlorobenzene and NOx: Performance enhancement and mechanism studies","authors":"Bo Yang,&nbsp;Liuying Wang,&nbsp;Qiuxiang Gu,&nbsp;Yujie Lei,&nbsp;Qiong Huang,&nbsp;Mindong Chen","doi":"10.1016/j.mcat.2024.114634","DOIUrl":"10.1016/j.mcat.2024.114634","url":null,"abstract":"<div><div>The transition metal titanium-doped Mn-Ce-O_x catalysts catalyst were employed to achieve synergetic removal of NO and CB at 180–220 °C. The Mn₅CeTi₅O_x catalyst with a molar ratio of Mn/Ce/Ti = 5:1:5 exhibits excellent activity, and the NO_x and CB removal efficiencies reach 96 % and 89 % at 160–220 °C, respectively. The selectivity for N₂ and CO₂ are 93 % and 78 %, respectively. The N₂-physisorption, NH₃-TPD, H₂-TPR and XPS results show that Ti doping makes the catalyst possess a mesoporous structure, suitable particle sizes, and excellent redox and Lewis site properties. All of these features contribute to the observed high NO and CB removal efficiency. The synergetic removal of CB and NO over Mn₅CeTi₅O_x results from the synergistic catalysis between the redox and the solid acid. On the one hand, in the synergistic removal process, CB and NH₃ are competitively adsorbed on the catalyst surface, resulting in a decrease in the NH₃-SCR activity. On the other hand, the removal of NO and CB has a synergetic effect. The byproduct NO₂ produced by the NH₃-SCR reaction promotes the oxidation of CB, which is beneficial for CB removal. Moreover, the consumption of NO₂ indirectly promotes the NH₃-SCR reaction, which partially compensates for the decrease in the NO removal efficiency caused by competitive adsorption between NH₃ and CB. Ti doping promotes the participation of the SCR byproduct NO₂ in the CBCO reaction and promotes the formation of maleic acid, an intermediate product of CB oxidation. In summary, the Mn₅CeTi₅O_x catalyst exhibits good activity for the synergistic removal of NO_x and CB and is a promising candidate for the effective and economical removal of NO and CB during waste incineration.</div></div>","PeriodicalId":393,"journal":{"name":"Molecular Catalysis","volume":"569 ","pages":"Article 114634"},"PeriodicalIF":3.9,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554784","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of the key residues of 1-Deoxy-D-Xylulose-5-Phosphate synthase on its catalysis","authors":"Yan-Fei Liang ,&nbsp;Shuai Feng ,&nbsp;Dan Wu,&nbsp;Meng Ma,&nbsp;Jin-Tao Ren,&nbsp;Qian Zhao,&nbsp;Wen-Yun Gao,&nbsp;Heng Li","doi":"10.1016/j.mcat.2024.114639","DOIUrl":"10.1016/j.mcat.2024.114639","url":null,"abstract":"<div><div>1-Deoxy-<span>D-</span>xylulose-5-phosphate synthase (DXS) is the first rate-limiting enzyme in the 2-methyl-<span>D-</span>erythritol-4-phosphate (MEP) terpenoid biosynthetic pathway. To explore the active sites of the protein, we made a series of mutations to the key amino acid residues of <em>Escherichia coli</em> DXS including H49, R420, D427, and R478. The results show that several mutants including H49Q lose almost all their catalytic activity in DXP synthesis, but the double-point mutants H49QD427H and H49QD427 N recover 100 % activity of the wild type enzyme. The kinetic characterization displays that the affinity of the double-point mutants for pyruvate and <span>D-</span>glyceraldehyde-3-phosphate only slightly decreases. We also assessed impact of the mutation on the oxidative decarboxylation activity of all the mutants. Despite the fact that H49QD427H and H49QD427 N get back the full activity with regard to DXP synthesis, their oxidase activity remains unrestored. Furthermore, we assayed the acceptor substrate spectrum of the mutants and the results show that a large portion of them catalyzes ligation between pyruvate and nitrosobenzene to form N-phenyl-N-hydroxyacetamide, whereas R420D, R420F, and D427H exhibit activity in connection of pyruvate and benzaldehyde to afford phenylacetocarbinol (PAC), with the first two mutants yielding (<em>S</em>)-PAC (yields 21 %-25 %, <em>ee</em> values 71–75 %) while D427H furnishing (<em>R</em>)-PAC (yield 41 %, <em>ee</em> value 91 %), implying the key role of D427 for the acceptor substrate recognition and the stereoselectivity of the enzyme. It is worth noting that this is the first report of DXS mutants that can recognize benzaldehyde as an acceptor substrate and generate both enantiomers of PAC.</div></div>","PeriodicalId":393,"journal":{"name":"Molecular Catalysis","volume":"569 ","pages":"Article 114639"},"PeriodicalIF":3.9,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554863","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis and evaluation of new mono- and binuclear salen complexes for the Cα-alkylation reaction of amino acid substrates as chiral phase transfer catalysts","authors":"Anahit M. Hovhannisyan ,&nbsp;Anna S. Tovmasyan ,&nbsp;Anna F. Mkrtchyan ,&nbsp;Karapet R. Ghazaryan ,&nbsp;Ela V. Minasyan ,&nbsp;Olgert L. Dallakyan ,&nbsp;Mikayel S. Chobanyan ,&nbsp;Hayk Zakaryan ,&nbsp;Giovanni N. Roviello ,&nbsp;Ashot S. Saghyan","doi":"10.1016/j.mcat.2024.114618","DOIUrl":"10.1016/j.mcat.2024.114618","url":null,"abstract":"<div><div>In this study, we present a series of Zn(II) mono- and Cu(II) binuclear salen complexes synthesized and assessed for their effectiveness in the Cα-alkylation reaction. Through systematic experimentation, it was observed that the introduction of a methoxy group at position 3 of the phenyl group in the salicylidene ligand led to a notable enhancement in asymmetric yield, while an allyl group reduced yield. Computational DFT calculations supported the involvement of the binuclear complex in the transition state of the reaction, elucidating the underlying mechanisms governing the observed catalytic behavior. A newly synthesized binuclear complex exhibited significantly higher catalytic activity compared to its mononuclear counterpart which could potentially be explained by increased intramolecular rigidity. This comprehensive investigation not only advances our understanding of structure-activity relationships in chiral salen complexes but also provides valuable insights for the rational design and optimization of catalysts for the asymmetric Cα-alkylation reaction.</div></div>","PeriodicalId":393,"journal":{"name":"Molecular Catalysis","volume":"569 ","pages":"Article 114618"},"PeriodicalIF":3.9,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preparation of 30%PMoV2@MOF@mSiO2 (MOF = MIL-101, HKUST-1, UiO-67, ZIF-8) catalysts and their oxidative desulfurization performance","authors":"Pushuang Xing ,&nbsp;Cong Li ,&nbsp;Yixin Chen,&nbsp;Rong-Lan Zhang","doi":"10.1016/j.mcat.2024.114613","DOIUrl":"10.1016/j.mcat.2024.114613","url":null,"abstract":"<div><div>PMoV₂ was encapsulated in four MOFs (MIL-101, HKUST-1, UiO-67, ZIF-8) with different cavity sizes and window sizes using a hydrothermal synthesis method. Then, a layer of mesoporous silica was coated on the surface of the MOFs to obtain four designed three-layer encapsulated catalysts 30%PMoV₂@MOF@mSiO₂. The physicochemical properties of the catalysts were characterized through various characterization methods, and the influence of different MOF window sizes of the four catalysts on the removal rate of four thiophene sulfides was investigated. The optimal reaction conditions were also explored for the optimal catalyst. The results indicate that under simulated fuel of 2400 ppm, 30%PMoV₂@UiO-67@mSiO₂ owns the highest catalytic activity. Under optimal conditions, the total removal rate of four thiophene compounds was 91.52 %, and after ten cycles, the efficiency could still reach 86.24 %. This is attributed to the sufficient cavity size of UiO-67, which provides assurance for the loading of PMoV₂ and the large window size, making it possible for the smooth reaction between sulfides and PMoV₂.</div></div>","PeriodicalId":393,"journal":{"name":"Molecular Catalysis","volume":"569 ","pages":"Article 114613"},"PeriodicalIF":3.9,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554861","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Carbon dot-based type I photosensitizers for photocatalytic oxidation reaction of arylboric acid and N-phenyl tetrahydroisoquinoline","authors":"Zhong-Lin Guo ,&nbsp;Kai-kai Niu ,&nbsp;Yu-Guang Lv ,&nbsp;Ling-Bao Xing","doi":"10.1016/j.mcat.2024.114625","DOIUrl":"10.1016/j.mcat.2024.114625","url":null,"abstract":"<div><div>Carbon dots (CDs) have emerged as promising materials for photocatalytic organic transformations due to their excellent photostability, tunable electronic properties, and environmental friendliness; However, the ability of CDs to selectively generate reactive oxygen species (ROS) and its integration with organic photocatalytic synthesis applications has always been a long-term challenge. In this work, we synthesized a new nitrogen and phosphorus co-doped carbon dots (N,P-CDs) with enhanced light absorption and notable efficiency in generating superoxide anion (O₂^•−) selectively. Leveraging the selective generation of superoxide anions, we achieved highly efficient photooxidation of boronic acids and N-phenyl tetrahydroisoquinolines, demonstrating the practical applicability of N,P-CDs as photocatalysts and represents good functional-group tolerance as well as a broad substrate scope. This study provides valuable insights into the design of carbon-based photocatalysts with controlled ROS generation, opening new avenues for environmentally benign organic transformations.</div></div>","PeriodicalId":393,"journal":{"name":"Molecular Catalysis","volume":"569 ","pages":"Article 114625"},"PeriodicalIF":3.9,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficient catalysis for the Baeyer-Villiger oxidation reaction of 2-adamantone in acidic deep eutectic solvents","authors":"Guiyi Zhao,&nbsp;Weiguang Wang,&nbsp;Kaixuan Yang,&nbsp;Ting Su,&nbsp;Zhiguo Zhu,&nbsp;Hongying Lü","doi":"10.1016/j.mcat.2024.114629","DOIUrl":"10.1016/j.mcat.2024.114629","url":null,"abstract":"<div><div>A deep eutectic solvent (DES) comprising p-toluenesulfonic acid (PTSA) and polyethylene glycol 200 (PEG200) was synthesized and applied to the Baeyer-Villiger (B-V) oxidation reaction of 2-adamantanone, which exhibited good catalytic effect and cyclic stability under relatively mild conditions. It was found that the hydrogen bond of DESs not only governed their physical properties, such as viscosity and electrical conductivity, but also influenced their chemical behavior, including the catalytic effect in B-V oxidation reaction. By adjusting the composition, the hydrogen bond properties can be optimized. This study aims to elucidate the intricate relationship between composition, hydrogen bond strength, and physicochemical properties of DESs, thereby establishing a preliminary theoretical foundation for a comprehensive understanding and construction of DESs systems. This provides a novel and promising environmentally friendly approach for the B-V oxidation reaction.</div></div>","PeriodicalId":393,"journal":{"name":"Molecular Catalysis","volume":"569 ","pages":"Article 114629"},"PeriodicalIF":3.9,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554859","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Upgrading the performance of syngas to ethanol via Mn modified Rh-based catalyst","authors":"Maosheng Yang ,&nbsp;Yang Feng ,&nbsp;Jungang Wang ,&nbsp;Zhongyi Ma ,&nbsp;Congbiao Chen ,&nbsp;Wei Zhang ,&nbsp;Shupeng Guo ,&nbsp;Hongjuan Xi ,&nbsp;Zhancheng Ma ,&nbsp;Bo Hou","doi":"10.1016/j.mcat.2024.114621","DOIUrl":"10.1016/j.mcat.2024.114621","url":null,"abstract":"<div><div>Significant strides have been undertaken to catalyze the production of ethanol from syngas, yet the challenge remains in developing catalysts that simultaneously exhibit high activity and selectivity. In this study, we designed a high-performance Rh-Mn catalyst. The CO conversion of finally screened 1Rh1Mn/TiO₂ catalyst is 51.8 %, and the total alcohol selectivity and ethanol yield are 72.1 % and 24.1 % respectively. This is the highest ethanol yield reported to date for Rh-based catalysts. Additionally, this catalyst also kept good stability. The outstanding performance is attributed to the fact that Mn facilitates the formation of Rh⁺ active sites, the process of CO insertion, and the generation of CH₃CHO and CH₃CO species—critical intermediates in ethanol production. In contrast, the unpromoted 1Rh/TiO₂ catalyst showed poor ethanol selectivity and mainly produced the Rh⁰ species, whereas the 1Rh1Mn/TiO₂ catalyst with the addition of Mn showed an increase in total alcohol and ethanol selectivity of 26.5 % and 31.3 %, respectively, as well as a reduction in CO₂ of 50.4 %. In addition, we elucidated the CO₂ generation and conversion pathways in the syngas to ethanol process, which is important for the effective utilization of carbon resources.</div></div>","PeriodicalId":393,"journal":{"name":"Molecular Catalysis","volume":"569 ","pages":"Article 114621"},"PeriodicalIF":3.9,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ZrO2 modified sulfonated charcoal-based catalysts for hydrolysis of biomass sugars and agricultural residues","authors":"Chenlin Wei ,&nbsp;Weitao Wang ,&nbsp;Huan Wang ,&nbsp;Jiaqi Zhu ,&nbsp;Zhen-Hong He ,&nbsp;Yangmin Ma ,&nbsp;Nianwen Guo ,&nbsp;Zhao-Tie Liu","doi":"10.1016/j.mcat.2024.114622","DOIUrl":"10.1016/j.mcat.2024.114622","url":null,"abstract":"<div><div>Furfural and 5-hydroxymethylfurfural obtained from sugars can be transformed into various chemicals. Conversion of sugars to furfural and 5-hydroxymethylfurfural are the typical reactions for the biomass feedstock transformation. In this study, a charcoal-based catalyst with acidic sites of Lewis and Brønsted acids was prepared to achieve an effective conversion of biomass sugars (xylose, glucose, and fructose) to furan compounds. By loading zirconium dioxide on the charcoal-based materials and then sulfonating it, the Lewis and Brønsted acids in the prepared solid acidic catalyst can be regulated to a suitable ratio. Under the optimal reaction condition, the furfural yield from xylose was 94.9 %, and the 5-hydroxymethylfurfural yields from glucose and fructose were 72.2 % and 99.9 %, respectively. Furthermore, a variety of sugars and agricultural wastes can be transformed into the corresponding furfural and 5-hydroxymethylfurfural in satisfactory yields over the catalyst.</div></div>","PeriodicalId":393,"journal":{"name":"Molecular Catalysis","volume":"569 ","pages":"Article 114622"},"PeriodicalIF":3.9,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Computational screening of Group VⅢ@C5N4 single-atom electrocatalysts for overall water splitting","authors":"Cuimei Li ,&nbsp;Dong Cao ,&nbsp;Dandan Guo ,&nbsp;Chun-Ran Chang","doi":"10.1016/j.mcat.2024.114619","DOIUrl":"10.1016/j.mcat.2024.114619","url":null,"abstract":"<div><div>Single-atom catalysts (SACs) have great potential for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) since their high atomic utilization and strong metal–support interactions. Herein, we develop TM@C₅N₄ (TM = Fe, Co, Ni, Ru, Rh, Pd, Os, Ir and Pt) catalysts via embedding Group VⅢ TM in holey C₅N₄ substrate and further evaluate their electrocatalytic activity using density functional theory (DFT) calculations. Systematical studies indicate that Fe@C₅N₄, Pd@C₅N₄ and Ir@C₅N₄ catalysts all exhibit excellent HER performance, which mainly because of their small Δ<em>G</em>_H* values of 0.101 eV, -0.114 eV and 0.070 eV, respectively. In parallel, Rh@C₅N₄ and Ir@C₅N₄ possess high OER activity along with low overpotential of 0.50 V, which is superior to the commercial IrO₂ catalyst (0.56 V). Obviously, Ir@C₅N₄ could be utilized as bifunctional electrocatalysts both HER and OER in water splitting. Furthermore, we analyze their correlative catalytic mechanisms using the molecular orbitals. Besides, biaxial strain modulation could effectively regulate the catalytic activity of HER and OER. Particularly, 2 % biaxial tensile strain could bring Ir@C₅N₄ superb HER/OER catalytic performance. Finally, we anticipate that this strain engineering would provide a new perspective for developing high-performance SACs for water splitting.</div></div>","PeriodicalId":393,"journal":{"name":"Molecular Catalysis","volume":"569 ","pages":"Article 114619"},"PeriodicalIF":3.9,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142554856","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}