Journal of Catalysis最新文献

{"title":"Palladium-catalyzed double activation of Si-C(sp3) bond of benzosilacyclobutenes synergized with unexpected olefin migration and ring-opening hydrolysis","authors":"Wen-Jing Shang ,&nbsp;Jia-Wei Si ,&nbsp;Jun-Hui Zhu ,&nbsp;Ji-Yuan Lv ,&nbsp;Zheng Xu ,&nbsp;Fei Ye ,&nbsp;Jian Cao ,&nbsp;Fuk Yee Kwong ,&nbsp;Li-Wen Xu","doi":"10.1016/j.jcat.2024.115788","DOIUrl":"10.1016/j.jcat.2024.115788","url":null,"abstract":"<div><div>A regioselective silicon-carbon bond activation of silacycles has emerged as a powerful strategy to access organosilicon compounds with functional groups. In contrast, progress in the development of new reaction systems for the tandem and double Si-C bond activation of silacycles has lagged. In this regard, there have been no reports of Si-C(sp³) bond activation of benzosilacyclobutenes and its tandem transformations. Herein, we address this challenging, disclosing the first example of palladium-catalyzed double Si-C bond activation of benzosilacyclobutenes and its tandem ring expansion and ring-opening transformations, in which various functionalized silanols that have ester groups are synthesized in this reaction. The main feature of this novel transformation is the highly selective activation of the Si-C(sp³) bond of benzosilacyles to achieve [4 + 2] cycloaddition with ester-activated alkynes and subsequent ring-opening and σ-bond metathesis with H₂O. Moreover, the DFT studies realized the origin of Si-C(sp³) bond activation, olefin migration, and ring-opening hydrolysis in the unprecedent reaction process.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"440 ","pages":"Article 115788"},"PeriodicalIF":6.5,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142398098","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}

{"title":"Every reaction Detail Matters: An in silico driven Step-by-Step Guide to understand the B2O3-Catalyzed CO2 to cyclic carbonates conversion","authors":"Nikunj Kumar ,&nbsp;Puneet Gupta","doi":"10.1016/j.jcat.2024.115787","DOIUrl":"10.1016/j.jcat.2024.115787","url":null,"abstract":"<div><div>The catalytic conversion of carbon dioxide (CO₂) to cyclic organic carbonates (COCs) via cycloaddition with epoxides offers a dual benefit of reducing CO₂ emissions while producing valuable chemical products. In this detailed <em>in silico</em> study, we employ density functional theory (DFT) to meticulously investigate the mechanisms underlying the B₂O₃/<em>n</em>-NBu₄Br-catalyzed cycloaddition of CO₂ and epoxides, following a step-by-step approach according to the reaction details. We provide a comprehensive comparison of the non-catalyzed, <em>n</em>-NBu₄Br alone, and B₂O₃/<em>n</em>-NBu₄Br-catalyzed pathways, emphasizing two distinct active sites within the B₂O₃ framework: <em>Site 1</em> (six-membered boroxol ring) and <em>Site 2</em> (open chain configuration). Our computational analysis highlights that the <em>Site 1</em>-catalyzed reaction pathway is more favorable, featuring a lower overall energy barrier of 26.8 kcal/mol, compared to 32.5 kcal/mol for the <em>Site 2</em>-catalyzed pathway. Detailed intrinsic bond orbital (IBO), natural adaptive orbital (NAdO) and distortion-interaction analysis (DIA) reveal significant differences in bonding properties and energy interactions, elucidating why <em>Site 1</em> exhibits superior catalytic activity over <em>Site 2</em>. These findings are corroborated by experimental observations, which indicate that ball milling B₂O₃ increases defect sites, thereby enhancing exposure of active sites <em>Site 1</em> and improving catalytic performance. This study provides an in-depth understanding of how the intrinsic properties of boron active sites influence the catalytic efficiency of B₂O₃, offering valuable insights for the design and optimization of metal-free catalysts for CO₂ conversion.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"439 ","pages":"Article 115787"},"PeriodicalIF":6.5,"publicationDate":"2024-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142379341","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}

{"title":"Can ZnO/Cu catalyst provide promising activity for glycerol direct dehydrogenation? A combined density functional theory and coverage-dependent microkinetics study","authors":"Wenfeng Wang ,&nbsp;Huixia Ma ,&nbsp;Jiqin Zhu ,&nbsp;Feng Zhou ,&nbsp;Haoxiang Xu ,&nbsp;Daojian Cheng","doi":"10.1016/j.jcat.2024.115786","DOIUrl":"10.1016/j.jcat.2024.115786","url":null,"abstract":"<div><div>Non-oxidative dehydrogenation (NODH) reaction of glycerol is a perfect atom economical technical route to produce higher-value 1,3-dihydroxyacetone (DHA). Cu-based catalyst (especially ZnO/Cu system), is known as active species for alcohol dehydrogenation, which may be also promising one for glycerol NODH. In this study, we combine coverage-dependent free energy profile using first-principle calculation, and microkinetic model, to investigate the NODH of glycerol on the ZnO/Cu(111) surface, and a detailed comparison is made with Cu (111) surface. The coverage-dependent microkinetic model takes into account the lateral adsorbate–adsorbate self-interactions and cross-interactions, and their effect on binding energy of both intermediate and transition state. Besides, it guarantees the reaction kinetics is based on the coverage self-consistent between surface model and microkinetic result under practically reaction conditions. Compared with coverage-dependent kinetics simulation (20 %–30 %), coverage-independent model overestimates the DHA selectivity on Cu (111) (over 90 %). Our coverage-dependent kinetics simulation illustrates that both glycerol conversion and DHA selectivity are most determined by the first dehydrogenation step (O<img>H bond scission) of glycerol on Cu (111). However, when ZnO cluster adsorbed on the Cu (111) surface, ZnO cluster promotes the electron transferring between glycerol and Cu sites, which accelerates O<img>H bond scission process of glycerol. Under coverage-dependent microkinetic model, the turnover frequency and selectivity of DHA on ZnO/Cu(111) get much improvement compared with Cu (111). Finally, the superior of ZnO/Cu(111) is further proved by continuous stirred tank reactor simulation, where NODH of glycerol need shorter residence times or lower temperature to reach 100 % conversion, as well as keep higher DHA selectivity.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"439 ","pages":"Article 115786"},"PeriodicalIF":6.5,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142377736","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}

{"title":"On the secondary promotion effect of Al and Ga on Cu/ZnO methanol synthesis catalysts","authors":"Benjamin Mockenhaupt ,&nbsp;Jil Gieser ,&nbsp;Sharif Najafishirtari ,&nbsp;Lorena Baumgarten ,&nbsp;Jelena Jelic ,&nbsp;Thomas Lunkenbein ,&nbsp;Erik-Jan Ras ,&nbsp;Jan-Dierk Grunwaldt ,&nbsp;Felix Studt ,&nbsp;Malte Behrens","doi":"10.1016/j.jcat.2024.115785","DOIUrl":"10.1016/j.jcat.2024.115785","url":null,"abstract":"<div><div>The structural and electronic effect of Al and Ga as ternary metals in Cu/ZnO catalysts for the methanol synthesis was examined. For this purpose, three zincian malachite-derived catalysts with the nominal Cu:Zn ratio of 70:30 were synthesized: an unpromoted binary catalyst (CZ) and two ternary catalysts with either 3 mol% Al (CZA) or Ga (CZG). Both Al and Ga showed a strong impact on the catalyst’s structure. Alongside the catalyst’s evolution from the co-precipitated precursors phase to the activated and reduced state, an improved microstructure and an increased BET surface area were found for the secondary promotor (Al or Ga) containing catalysts. Moreover, a sequence of chemisorption experiments allowed us to quantify and differentiate between Cu^surf and Zn^red surface species in the activated catalysts. Considering the specific copper surface areas, DRIFTS data and catalytic results, an additional electronic promotion of Al and Ga is proposed. As demonstrated by Ga K-edge XANES, this promotion effect is related to doping of the ZnO support and enhances the reducibility of ZnO to form more Zn^red sites. This effect is stronger for Al leading to a more pronounced Zn^red overlayer on the Cu surface due to SMSI. In methanol synthesis, this results in a performance order CZA &gt; CZG &gt; CZ.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"439 ","pages":"Article 115785"},"PeriodicalIF":6.5,"publicationDate":"2024-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142374485","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of 4,4′-dialkyl-2,2′-bipyridine ligands on the hydrolysis of dichlorodioxomolybdenum(VI) catalyst precursors and the switch from homogeneous epoxidation to heterogeneous systems","authors":"Diana M. Gomes,&nbsp;Ana C. Gomes,&nbsp;Patrícia Neves,&nbsp;Filipe A. Almeida Paz,&nbsp;Anabela A. Valente,&nbsp;Isabel S. Gonçalves,&nbsp;Martyn Pillinger","doi":"10.1016/j.jcat.2024.115782","DOIUrl":"10.1016/j.jcat.2024.115782","url":null,"abstract":"<div><div>Molybdenum catalysts have been industrially recognized for decades for liquid phase epoxidation, which is an important chemical reaction process, since epoxides are used for many industrial applications. In this work, molybdenum oxide hybrid catalysts, prepared by a reflux hydrolysis methodology, performed effectively as heterogeneous catalysts or reaction-induced self-separating catalysts under mild reaction conditions; in the two cases, the catalyst separation and reuse are facilitated. Specifically, catalysts with the general formula [MoO₃(L)], possessing polymeric chain-like (L = 4,4′-dimethyl-2,2′-bipyridine (<strong>1</strong>)) or oligomeric (L = 4,4′-dinonyl-2,2′-bipyridine (<strong>2</strong>)) structures comprising corner-sharing {MoO₄N₂} units, were synthesized and characterized by various complementary techniques (ATR FT-IR, Raman, ¹³C{¹H} CP MAS NMR spectroscopy, PXRD, SEM, TGA, elemental analysis, ICP-OES and N₂ sorption isotherms). Small chemical differences in the organic synthesis precursor had important structure directing effects on the type of hybrid material formed. The hybrids promoted olefin epoxidation with H₂O₂ or <em>tert</em>-butylhydroperoxide (TBHP) as oxidant. For example, <strong>1</strong> catalyzed the conversion of biobased olefins (70 °C) and lignin-based isoeugenol (50 °C) with TBHP to useful bioproducts, in heterogeneous phase, leading to an epoxide yield of 100 % for <em>DL</em>-limonene (3:1 M molar ratio of 1,2-epoxy-<em>p</em>-menth-8-ene to 1,2:8,9-diepoxy-<em>p</em>-menthane), 81 % epoxide yield for fatty acid methyl esters, and 80 % Licarin A selectivity at 40 % isoeugenol conversion. For dienes (<em>DL</em>-limonene, methyl linoleate), kinetic modelling studies suggested that the formation of the monoepoxides was faster than that of diepoxides, accounting for enhanced monoepoxide selectivity.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"439 ","pages":"Article 115782"},"PeriodicalIF":6.5,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142370094","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ligand engineering regulates the electronic structure of Ni-N-C sites to promote electrocatalytic acetylene semi-hydrogenation","authors":"Kai Xu,&nbsp;Mingqiang Liu,&nbsp;Xiaohong Song,&nbsp;Shengyuan Xu,&nbsp;Kefeng Xie","doi":"10.1016/j.jcat.2024.115784","DOIUrl":"10.1016/j.jcat.2024.115784","url":null,"abstract":"<div><div>Compared with traditional thermal catalytic hydrogenation technology, electrocatalytic acetylene semi-hydrogenation (EASH) is a green and environmentally friendly method. EASH utilizes renewable electricity under normal temperature and pressure conditions, and uses water as a hydrogen source to electrocatalytically semi-hydrogenate acetylene to ethylene. Ni-based single-atom catalysts (SACs) have shown good application prospects in EASH, but there is still much room for optimization. The axial coordination regulation of the active center is a potential means to improve its activity. In this work, the activity and selectivity of NiN₄ SACs with 14 axial ligands (X) for EASH were systematically studied via density functional theory (DFT). First, the binding energy and ab initio molecular dynamics simulation results show that all the NiN₄-X can exist stably. Second, the Gibbs free energy diagram shows that the activation and adsorption of C₂H₂ is the rate-determining step of the reaction. The introduction of the –ONO ligand enhances the activation and adsorption of C₂H₂ by NiN₄, which is beneficial to the occurrence of EASH and inhibits the side reactions of hydrogen evolution. The two parameters <span><math><mrow><msub><mrow><mspace></mspace><mi>Δ</mi><mi>G</mi></mrow><mrow><mo>∗</mo><mi>C</mi><mi>H</mi><mi>C</mi><mi>H</mi></mrow></msub></mrow></math></span> and <span><math><mrow><msub><mrow><mspace></mspace><mi>Δ</mi><mi>G</mi></mrow><mrow><mo>∗</mo><msub><mrow><mi>CH</mi></mrow><mn>2</mn></msub><mi>C</mi><msub><mi>H</mi><mn>3</mn></msub></mrow></msub></mrow></math></span> can be used as characteristic descriptors to predict the activity and selectivity of EASH. Finally, the catalytic activity mechanism was explained from the perspective of electrons and orbitals, and it was found that the <span><math><mrow><msub><mi>d</mi><msup><mrow><mi>z</mi></mrow><mn>2</mn></msup></msub></mrow></math></span> orbital played a leading role in the axial ligand regulation of C₂H₂ catalytic activity. This work provides a new method for the development of efficient EASH catalysts.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"439 ","pages":"Article 115784"},"PeriodicalIF":6.5,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142370139","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}

{"title":"Air-stable, well-defined palladium–BIAN–NHC chloro dimer: Highly efficient N-Heterocyclic carbene (NHC) catalyst platform for Buchwald–Hartwig C–N cross-coupling reactions","authors":"Jin Zhang ,&nbsp;Jianglong Cai ,&nbsp;Xue Li ,&nbsp;Gaopeng Zhang ,&nbsp;Wenxuan Yan ,&nbsp;Renjie Li ,&nbsp;Jianbo Tong ,&nbsp;Michal Szostak","doi":"10.1016/j.jcat.2024.115783","DOIUrl":"10.1016/j.jcat.2024.115783","url":null,"abstract":"<div><div>Buchwald-Hartwig amination has become the fundamental method for constructing molecular architectures throughout chemical research, including the synthesis of pharmaceutical agents, natural products, fine chemicals, and advanced materials. Herein, we report air-stable, well-defined palladium–BIAN–NHC chloro dimer, [Pd(BIAN–NHC)(<em>μ</em>-Cl)Cl]₂, for Buchwald-Hartwig C–N cross-coupling reactions of aryl halides. This rapidly activating catalyst framework merges the reactive properties of palladium chloro dimers, [Pd(NHC)(<em>μ</em>-Cl)Cl]₂, with the structural features of acenaphthoimidazol-2-ylidenes. [Pd(BIAN–NHC)(<em>μ</em>-Cl)Cl]₂ is the most reactive Pd(II)–NHC precatalyst to date, undergoing fast activation under both inert atmosphere and aerobic conditions. The catalyst shows an excellent reactivity in Buchwald-Hartwig amination of aryl halides (59 examples), including challenging substrates, diamination and direct functionalization of pharmaceuticals. The steric protection enables high reactivity under both inert atmosphere and aerobic conditions. [Pd(BIAN–IPr)(<em>μ</em>-Cl)Cl]₂ should be routinely utilized for the synthesis of C–N bonds to make valuable amines, where it replaces the most commonly deployed at present IPr (IPr = 1,3-bis(2,6-isopropyl)imidazol-2-ylidene).</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"439 ","pages":"Article 115783"},"PeriodicalIF":6.5,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142369530","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}

{"title":"Structure sensitivity in the formic acid-driven catalytic transfer hydrogenation of maleic acid to succinic acid over Pd/C catalysts","authors":"A. Orozco-Saumell ,&nbsp;M. Retuerto ,&nbsp;A.C. Alba-Rubio ,&nbsp;P. Maireles-Torres ,&nbsp;J. Iglesias ,&nbsp;R. Mariscal ,&nbsp;M. López Granados","doi":"10.1016/j.jcat.2024.115780","DOIUrl":"10.1016/j.jcat.2024.115780","url":null,"abstract":"<div><div>A series of carbon-supported palladium catalysts (Pd/C) with average particle size in the range from 3 to 7 nm was prepared by varying the Pd loading. These materials and the influence of their physicochemical properties in the catalytic transfer hydrogenation (CTH) of maleic acid (MAc) to succinic acid (SAc) using formic acid (FAc) as H₂ donor were evaluated. The chemical, textural, and surface properties were studied by a number of characterization techniques (ICP-OES, XRD, TEM, and XPS). It was found that the intrinsic rate of SAc formation per surface Pd atom (turn-over frequency, TOF Pd_sur) is structure-sensitive. The TOF Pd_sur rate increases with the particle size following a volcano-type curve, reaching a maximum for an average particle size of ca. 6 nm. Assuming a cuboctahedral shape with a cubic close-packed structure, an approximation frequently adopted for Pd particles, it was found that, for the series of catalysts, neither the calculated TOF of Pd surface atoms at low coordination sites nor at high coordination are constant. This suggests that no geometric effect is responsible for the structure-sensitivity. Among the different Pd species present in the catalysts (i.e., metallic Pd (Pd⁰), palladium carbide (PdC_x), and oxidized Pd), it was observed that the relative number of surface Pd⁰ sites also follows a volcano-type curve, which indicates that Pd⁰ sites are necessarily involved in the most active centers. For particles with an average size larger than 4 nm, the TOF rate of surface Pd⁰ sites was constant and in the range of 0.12 s⁻¹. For smaller sizes, a more accurate determination of their Pd⁰ surface concentration is required to obtain reliable surface Pd⁰ TOF rates.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"439 ","pages":"Article 115780"},"PeriodicalIF":6.5,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142369527","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}

{"title":"Palladium-Catalyzed branch hydroaminocarbonylation of terminal alkynes with nitroarenes","authors":"Zhiping Yin ,&nbsp;Weiheng Yuan ,&nbsp;Chenwei Liu ,&nbsp;Xiaowen Qin ,&nbsp;Tiefeng Xu ,&nbsp;Xiao-Feng Wu","doi":"10.1016/j.jcat.2024.115781","DOIUrl":"10.1016/j.jcat.2024.115781","url":null,"abstract":"<div><div>We report an innovative palladium-catalyzed hydroaminocarbonylation approach that efficiently converts nitroarenes and terminal alkynes into α,β-unsaturated amides. This method, with broad substrate compatibility, delivers 32% to 87% yields with excellent regioselectivity. Central to the effectiveness of this reaction are the bipyridine ligand and salicylic acid, which play pivotal roles in optimizing both selectivity and product yield. Mechanistic experiments revealed that arylamine serves as a critical intermediate in the overall reaction, highlighting a unique pathway in the catalytic cycle. In contrast to conventional procedures, this protocol employs diverse nitroarenes and Mo(CO)₆ as direct nitrogen and solid carbonyl sources, streamlining the process and enhancing safety by reducing the reliance on hazardous CO gas.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"439 ","pages":"Article 115781"},"PeriodicalIF":6.5,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142369528","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}

{"title":"A detailed characterization study of Ni/CeO2 catalysts identifies Ni availability as the primary factor affecting CO2 methanation performance","authors":"Sining Chen ,&nbsp;Luke Higgins ,&nbsp;Ilenia Giarnieri ,&nbsp;Patricia Benito ,&nbsp;Andrew M. Beale","doi":"10.1016/j.jcat.2024.115778","DOIUrl":"10.1016/j.jcat.2024.115778","url":null,"abstract":"<div><div>The structure of a catalyst has a strong impact on its performance. Here we investigate the physicochemical properties of Ni/CeO₂ in an attempt to draw structure–activity relationships for CO₂ methanation. A combination of characterisation methods (X-ray diffraction (XRD), 4D Scanning Transmission Electron Microscopy (4D-STEM), CO chemisorption and oxygen storage capacity study etc.) clearly demonstrates the effect of Ni crystallite size, Ni availability (i.e. catalytically accessible Ni) and oxygen vacancies at the Ni-CeO₂ interface in Ni/CeO₂ during CO₂ methanation. Among them, the role of exposed Ni active sites is highlighted, and two possible optimisation schemes i.e. changing the support calcination temperature and the final calcination atmosphere are proposed to obtain a better dispersal of Ni NPs (nanoparticles) on CeO₂. Both modification methods do not affect the reaction route, and the activity differences of Ni/CeO₂ can be explained by the various hydrogenation rate of formate species, as confirmed by <em>in situ</em> diffuse-reflectance infrared Fourier-transform spectroscopy (DRIFTS) measurements.</div></div>","PeriodicalId":346,"journal":{"name":"Journal of Catalysis","volume":"439 ","pages":"Article 115778"},"PeriodicalIF":6.5,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142369531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}