ACS Catalysis 最新文献

{"title":"Targeted Modification of Zeolites for Exceptionally Active and Selective Generation of PX and Light Olefins from Methanol–Toluene Co-Conversion","authors":"Yimo Wu, Nan Wang, Enze Chen, Haohao Feng, Dong Fan, Yang Yu, Li Wang, Te Ji, Zhengxi Yu, Jingfeng Han, Yingxu Wei, Zhongmin Liu","doi":"10.1021/acscatal.4c07812","DOIUrl":"https://doi.org/10.1021/acscatal.4c07812","url":null,"abstract":"External surface modification is an effective means of achieving selective production in the acid-catalyzed process over the zeolite. However, catalyst modification, including external surface modification, often fails to break the seesaw effect between the reaction activity and selectivity. In the present work, an acid site-targeted chemical adsorption deposition (acid site-chemical adsorption–deposition (ASCAD)) method is applied to precisely control the deposition of silica. The modified ZSM-5 (ZSM-5-ASCAD) shows notable improvements in shape selectivity and catalytic activity in methanol–toluene coconversion. The total selectivity of light olefins and paraxylene (PX) reaches 94%, and the proportion of PX among xylene isomers is 99.5%. Meanwhile, toluene conversion is maintained at 43%, which is much higher than that over ZSM-5 modified by the conventional chemical liquid deposition (CLD) method (18%). Applying multiple techniques, including time of flight secondary ion mass spectrometry for depth profiling, the zero length column method combined with infrared microscopy (IRM) for diffusion evaluations and isotope labeling technology to reveal the mechanism and reaction pathway, we confirm that the ASCAD method achieves a minimized silica deposition that precisely shields the acid sites on the external surface while introducing only a slight impact on the diffusion compared to the severe diffusion depression of the CLD method. ASCAD modification effectively suppresses unwanted and uncontrollable side reactions and maintains high reactant conversion simultaneously. This unique modification method minimizes the disparity in mass transfer capability between the reactant methanol and toluene, which has not been achieved with other modification methods before, leading to enhanced methanol–toluene coconversion within the ZSM-5 crystal and exhibiting promoted ethene production and super high PX selectivity at the same time. Targeted modification of the zeolite surface provides an effective approach to simultaneously enhancing the activity and shape selectivity of zeolite-catalyzed reactions.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"30 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143470453","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":"Ir-Catalyzed, Nitrogen-Directed C(sp3)–H and C(sp2)–H Borylation with a Spiro-Fluorene-Indenoindenyl Ligand","authors":"Tomonori Inoue, Yu Sato, Yuki Nagashima, Ken Tanaka","doi":"10.1021/acscatal.4c07249","DOIUrl":"https://doi.org/10.1021/acscatal.4c07249","url":null,"abstract":"We have developed a strategy to facilitate the nitrogen-directed C–H borylation using an Ir(cod) catalyst with a spiro-fluorene-indenoindenyl (SFI) ligand through CH (ligand)−π (substrate) interactions and the selective formation of an electron-rich and less bulky IrH(Bpin) intermediate rather than Ir(Bpin)₂. This Ir catalyst allows the nitrogen-directed regioselective C(sp³)–H and C(sp²)–H borylation with HBpin at near room temperature without photoirradiation with a broad substrate scope.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"127 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143462302","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":"Volcano Relationship of Electron Polarization Degree in Core–Shelled Ni@C Catalysts and Catalytic Activity for Hydrogen Oxidation Reaction","authors":"Jing Liu, Wanqing Yu, Mengdi Wang, Jie Gao, Xuejing Cui, Luhua Jiang","doi":"10.1021/acscatal.5c00053","DOIUrl":"https://doi.org/10.1021/acscatal.5c00053","url":null,"abstract":"Developing efficient nonprecious electrocatalysts for the hydrogen oxidation reaction (HOR) is crucial for advancing alkaline exchange membrane fuel cells (AEMFCs). A promising approach to enhance the performance of a HOR catalyst involves tuning metal–support interaction by encapsulating metal nanoparticles in carbon shells. However, the precise impact of the carbon shell on catalytic activity remains to be fully understood, yet it is crucial to guide the rational design of core–shell structured catalysts. In this study, with a sequence of well-designed Ni catalysts coated by heteroatom-doped-carbon layers (including Ni@BNC, Ni@SNC, and Ni@NC), we discover a volcano-type relationship between the electron polarization degree and the HOR activity. Experimental and theoretical analyses show heteroatom doping adjusts the carbon layer’s electron-withdrawing ability, modulating the Ni core’s d-band center and hydrogen binding energy (HBE). Additionally, heteroatom doping shifts the potential of zero charge (PZC) negatively and enhances hydrogen bond connectivity, facilitating hydroxyl ion transfer. As a result, Ni@BNC achieves optimal HBE and enhanced water adsorption, placing it at the volcano summit for the HOR activity. This study establishes a delicate volcano relationship between the electron polarization degree and the HOR activity of core–shelled catalysts by shedding light on the underlying determining factors, both the d-band center of metals and the surface PZC, related tightly with the HBE and hydrogen bond connectivity/water adsorption.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"13 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143470459","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":"Molybdenum Carbide Nanoparticles in Silicalite-1 Zeolite for CO2-Assisted Propane Dehydrogenation","authors":"Bing Xu, Jun Ma, Shuo Cao, Ying Ma, Giuliano Giambastiani, Yuefeng Liu","doi":"10.1021/acscatal.4c07162","DOIUrl":"https://doi.org/10.1021/acscatal.4c07162","url":null,"abstract":"Molybdenum carbides (MoC_<i>x</i>) have been shown to be effective catalysts in a number of challenging industrial-relevant reactions. Their promising performance combined with their natural abundance and low cost make them valuable alternatives to the use of noble metals. However, an often too limited exposure of active sites in micrometer-sized MoC_<i>x</i> particles combined with their strong acid features depletes the ultimate catalytic performance for C–H bond activation in alkane dehydrogenation. In this work, we have synthesized highly dispersed molybdenum carbide nanoparticles (NPs) embedded into the framework of silicalite-1 zeolite (MoC_<i>x</i>/Si-1) to be employed in direct and/or CO₂-assisted propane dehydrogenation reaction. The as-synthesized MoC_<i>x</i>/Si-1 exhibits enhanced CO₂-assisted oxidative propane dehydrogenation (CO₂-ODHP) performance with rates up to 172.8 μmol g_cat^–1 min^–1 with C₃H₆ selectivity &gt; 94% (61.5% C₃H₆ selectivity for bulk β-Mo₂C), which is attributed to the moderate catalyst acidity, better H-spillover property, and the appropriate propane adsorption or propylene desorption mechanisms on such micropore systems. Extensive characterization data prove that a high concentration of exposed molybdenum oxycarbide (MoC_<i>x</i>O_<i>y</i>) sites was crucial for CO₂-ODHP. Propane is converted on MoC_<i>x</i>O_<i>y</i> active sites to propylene and H₂O, while the MoC_<i>x</i>O_<i>y</i> are reduced into MoC_<i>x</i> sites. Subsequently, the reduced MoC_<i>x</i> sites are reoxidized by CO₂ into MoC_<i>x</i>O_<i>y</i> active sites and CO gas. This work designs molybdenum carbide nanoparticles embedded in Si-1 zeolite, demonstrates high activity and propylene selectivity in CO₂-assisted propane dehydrogenation, and provides guidance for the application of carbides in alkane dehydrogenation.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"2 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143462157","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":"Highly Active and Stable Single-Atom Cobalt in Zeolite for Acetylene Semihydrogenation","authors":"Essa Alhashmi, George Ebri, Klaus Hellgardt","doi":"10.1021/acscatal.4c07063","DOIUrl":"https://doi.org/10.1021/acscatal.4c07063","url":null,"abstract":"Ethylene produced from steam cracking includes an acetylene impurity of 0.5–3%, harming the downstream polymerization process. To achieve polymer-grade ethylene, acetylene must be removed by chemoselective hydrogenation to ethylene without overhydrogenation to ethane. The current state-of-the-art process uses supported Pd nanoparticles (NPs) and toxic CO injections to poison the active sites, which is expensive and shows poor ethylene selectivity. To tackle this issue, the use of single-atom catalysts can offer a way to simultaneously improve selectivity through preferential desorption of ethylene over its hydrogenation and minimize cost. In particular, single-atom cobalt catalysis can address both of these issues. However, to date, single-atom cobalt has not been tested for this reaction. Herein, we present a cost-effective monometallic, cobalt-anchored zeolite Y (Co₁@Y) catalyst, synthesized via an in situ hydrothermal method, holding isolated active cobalt atoms that efficiently and selectively hydrogenate acetylene to ethylene. Characterization techniques proved the absence of NPs and the presence of single-atom cobalt sites. The catalyst achieved an ethylene selectivity of 90 ± 2% at full acetylene conversion, with a stable performance for over 400 h. Co₁@Y achieved TOF_ethylene greater than the previously reported zeolite-supported single-atom catalysts by ∼5 times. Varying the dispersion of cobalt from an NP to a single atom modified the reaction mechanism from associative to dissociative, remarkably improving catalytic activity and selectivity. This strategy can be extended to other relatively inactive metals and other hydrogenation reactions.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"6 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143470454","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":"Enhanced Photocatalytic Conversion of CO2 by H2O over Ag@Cr Cocatalyst-Modified ZnTa2O6","authors":"Kio Kawata, Shoji Iguchi, Shimpei Naniwa, Masamu Nishimoto, Kentaro Teramura","doi":"10.1021/acscatal.4c06530","DOIUrl":"https://doi.org/10.1021/acscatal.4c06530","url":null,"abstract":"A zinc tantalate (ZnTa₂O₆) photocatalyst modified with an Ag cocatalyst via ultrasonic reduction (denoted as Ag(USR)/ZnTa₂O₆) exhibited higher activity for the photocatalytic conversion of CO₂ by H₂O than Ag/ZnTa₂O₆ prepared by other widely used methods. However, the CO formation rate was low. In this study, a photocatalyst was prepared by coating the Ag nanoparticles of Ag(USR)/ZnTa₂O₆ with Cr(OH)₃·<i>x</i>H₂O via the photodeposition (PD) method (denoted as Cr(PD)/Ag(USR)/ZnTa₂O₆) to increase the CO formation rate. Cr(PD)/Ag(USR)/ZnTa₂O₆ produced CO at the maximum formation rate of ∼600 μmol h^–1, which was 50 and 8.5 times higher than those of bare ZnTa₂O₆ and Ag(USR)/ZnTa₂O₆, respectively. Furthermore, an induction period was observed during the time course of photocatalytic activity. The scanning electron microscopy images highlighted that Ag nanoparticles migrate to a specific site on the surface of ZnTa₂O₆ as photoirradiation proceeded, causing the rearrangement of Ag nanoparticles during this period. This rearrangement caused the separation of the photocatalytic reaction field, achieving high activity toward the photocatalytic conversion of CO₂ because of the efficient reduction and oxidation reactions. Moreover, inductively coupled plasma mass spectrometry and ultraviolet–visible absorption spectroscopy revealed that Cr³⁺ in Cr(PD)/Ag(USR)/ZnTa₂O₆ is oxidized to dissolvable CrO₄^2– during the induction period. These CrO₄^2– anions in solution were found to play a crucial role in maintaining the Cr layer of Cr(PD)/Ag(USR)/ZnTa₂O₆.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"14 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143462301","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":"Dynamic Interplay between Particle Size and Strong Metal Support Interaction in Rh/TiO2 Tuning the Selectivity of CO2 Hydrogenation","authors":"Zilin Wang, Dongbo Shu, Haijie Chen, Chuanmin Ding, Junwen Wang, Yan Lv, Qingqing Gu, Aiqin Wang, Bing Yang","doi":"10.1021/acscatal.4c07685","DOIUrl":"https://doi.org/10.1021/acscatal.4c07685","url":null,"abstract":"The regulation of selectivity in CO₂ hydrogenation is of great importance and has been intensively studied for the utilization of CO₂. The particle size and metal–support interaction are proven to be key factors influencing the selectivity of CO₂ hydrogenation. However, the dynamic structure evolution during real reaction conditions and their impact on the selectivity are still poorly understood. Here in this work, we reported the crystal-phase-mediated dynamic restructuring of the Rh/TiO₂ catalyst during reaction that strongly modulates the mutual interaction of dynamic size stability and strong metal–support interaction (SMSI) encapsulation of the Rh catalyst and thus the selectivity of CO₂ hydrogenation toward CO/CH₄. By utilizing state-of-the-art characterizations, the interplay between dynamic size distribution and SMSI of the Rh catalyst on TiO₂ was clearly elucidated. The selectivity of CO₂ hydrogenation was prone to the particle size in the low reaction temperature range (225–275 °C) while highly depending on SMSI at high reaction temperatures (350–400 °C). Remarkably, anatase TiO₂ promotes small Rh particles and strong SMSI at the low-temperature range, rutile TiO₂ facilitates large particles but high-temperature SMSI encapsulation, while the P25 phase favors large Rh particles without encapsulation. The <i>in situ</i> DRIFTS experiments further reveal that all Rh/TiO₂ catalysts follow the hydrogenation path via *HCOO as an intermediate, where the large Rh particle size facilitates deep hydrogenation of *HCOO to CH₄, whereas the TiO_<i>x</i> encapsulation favors the *HCOO decomposition to CO due to the suppressed H₂ activation. Our results provide dynamic insight for the restructuring of the active sites in the Rh/TiO₂ catalyst that tunes the selectivity of CO₂ hydrogenation and opens up a route for the rational design of supported metal catalysts based on their dynamic structures.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"16 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143462319","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":"Selective C2+ Alcohol Synthesis from Syngas Boosted by MnOx-Doped CoFe Bimetallic Alloy Carbide Catalysts","authors":"Zhuoshi Li, Guangyuan Luo, Xiaofeng Pei, Chenxi Gao, Jing Lv, Shouying Huang, Yue Wang, Xinbin Ma","doi":"10.1021/acscatal.4c07408","DOIUrl":"https://doi.org/10.1021/acscatal.4c07408","url":null,"abstract":"Direct synthesis of higher alcohols (HA) from syngas is an attractive route for converting nonpetroleum carbon feedstocks into high value-added fuels and chemical products. CoFe alloy carbide catalysts are promising for this reaction, but facilitating the alloy carbide formation is still challenging. Herein, a series of Mn-promoted catalysts with regulated proximity between Mn and CoFe₂O₄ were prepared. It was found that the manganese species with close intimacy greatly facilitated the formation of ε’-(Co_<i>x</i>Fe_1–<i>x</i>)_2.2C, reaching a maximum content of 88.4 wt % over the Mn_0.25Co₁Fe₂ catalyst. A space-time yield toward HA of 137.9 mmol·g_(Co+Fe)^–1·h^–1 with stability over 300 h was achieved over this catalyst, ranking top among the literature. In addition, MnO_<i>x</i> also greatly promoted the CO dissociation. The closely interacted MnO_<i>x</i> and ε’-(Co_<i>x</i>Fe_1–<i>x</i>)_2.2C sites benefited the coupling of CH_<i>x</i>* and CO*/CHO*, leading to the modification of the Anderson-Schulz–Flory law and the enhanced C₂₊ alcohols fraction in total alcohols up to 94.1 wt %. Moreover, the Mn content was also optimized. This promotional effect of manganese may provide possibilities for the use of CoFe alloy carbide catalysts in higher alcohol synthesis.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"66 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143462303","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":"Highly Efficient CO2 Hydrogenation to Linear α-Olefins on FeZnK Catalysts with Balanced Zn–O–Fe Interfaces and Fe5C2 Species","authors":"Jian Han, Wei Liu, Lina Zhang, Hao Ren, Chongchong Wu, Jian Zhang, Chenfan Gong, Guoming Yang, Haiyan Yang, Siran Zhang, Hao Wang, Te Ji, Jiong Li, Peng Gao","doi":"10.1021/acscatal.4c07784","DOIUrl":"https://doi.org/10.1021/acscatal.4c07784","url":null,"abstract":"C₄₊ linear α-olefins (LAOs) synthesis from direct CO₂ hydrogenation is a promising strategy to realize the fixation of CO₂ to high-value chemical products. However, identifying active catalysts with satisfactory activity and selectivity is quite difficult nowadays. Herein, we fabricate a series of iron–zinc–potassium (FeZnK) catalysts via a citric acid-mediated combustion method that can both actively and selectively synthesize LAOs from CO₂ hydrogenation. The Fe₁Zn_0.1K_0.1 catalyst with balanced Zn–O–Fe interfaces and active Fe₅C₂ species provides an LAOs selectivity of 44.7% at a high CO₂ conversion of 43.3% in CO₂ hydrogenation. Notably, the space–time yield of LAOs over Fe₁Zn_0.1K_0.1 reaches 0.40 g·g_cat^–1·h^–1, surpassing the performance of current state-of-the-art Fe-based catalysts. The reaction results and multiple characterizations reveal that the introduction of an appropriate amount of Zn composition can not only enhance the CO₂ adsorption ability by forming Zn–O–Fe interfaces but also improve the LAOs selectivity by promoting the formation of active Fe₅C₂ species. Interestingly, active Fe₅C₂ species tend to form in the bulk phase of the FeZnK catalysts, which are more closely correlated with catalytic activity. <i>In situ</i>/<i>ex situ</i> characterizations combined with H₂/D₂ exchange and CO pulse hydrogenation probe experiments elucidate the structure–activity relationship and reaction mechanism. Furthermore, Fe₁Zn_0.1K_0.1 shows a 160 h long-time on-stream stability, indicating its strong potential as an industrial catalyst for direct CO₂ conversion to high-value LAOs.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"107 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143451526","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":"Effective COx Suppression by a Na4Mg(WO4)3 Promoter in Chemical Looping Oxidative Dehydrogenation of Ethane","authors":"Dennis Chacko, Luke M. Neal, Bar Mosevitzky Lis, Junchen Liu, Andrew Pedersen, Israel E. Wachs, Fanxing Li","doi":"10.1021/acscatal.4c07851","DOIUrl":"https://doi.org/10.1021/acscatal.4c07851","url":null,"abstract":"Chemical looping oxidative dehydrogenation (CL-ODH) of ethane represents a promising intensification strategy to produce ethylene. A key aspect to improving CL-ODH performance revolves around mitigating the formation of CO_<i>x</i> from the ethane feedstock and ethylene product. This work reports Na₄Mg(WO₄)₃ as a highly effective promoter for the Mg₆MnO₈-based redox catalyst for ethane ODH through the enrichment on the oxide surface by Na₄Mg(WO₄)₃ to suppress CO_<i>x</i> formation. Compared to the state-of-the-art Na₂WO₄-promoted Mg₆MnO₈ catalyst, the Na₄Mg(WO₄)₃ promoter lowers CO_<i>x</i> selectivity by up to 88% on a relative basis while achieving up to 70% C₂₊ olefin yield. This represents some of the highest olefin selectivity and yield values among previously reported CL-ODH catalysts. The role of the promoter in suppressing nonselective oxidation was investigated using <i>in situ</i> X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), H₂-temperature-programmed reduction (H₂-TPR), C₂H₆-temperature-programmed surface reaction (TPSR), methanol-TPSR with <i>in situ</i> diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), and <i>in situ</i> Raman spectroscopy. Compared with the Na₂WO₄-promoted Mg₆MnO₈, the Na₄Mg(WO₄)₃ promoter exhibits improved dispersion of the promoter on Mg₆MnO₈ and inhibits the release of lattice oxygen from the Mg₆MnO₈ phase. Meanwhile, a higher average Mn oxidation state is maintained for the Mg₆MnO₈ phase. This suggests that the uniformity of promoter dispersion over the Mg₆MnO₈ phase, coupled with reduced lattice oxygen transport kinetics, is crucial in suppressing the formation of CO_<i>x</i> formation.","PeriodicalId":9,"journal":{"name":"ACS Catalysis ","volume":"13 1","pages":""},"PeriodicalIF":12.9,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143462317","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}