Catalysis Science & Technology最新文献_第10页

Investigation of titania and ceria support effects in nickel catalyzed CO2 methanation† 镍催化二氧化碳甲烷化过程中二氧化钛和铈支撑效应的研究

IF 4.4 3区化学

Catalysis Science & Technology Pub Date : 2024-08-12 DOI: 10.1039/d4cy00461b

{"title":"Investigation of titania and ceria support effects in nickel catalyzed CO2 methanation†","authors":"","doi":"10.1039/d4cy00461b","DOIUrl":"10.1039/d4cy00461b","url":null,"abstract":"<div>Ni catalysts, supported on TiO2 or CeO2, are active and selective for CO2 methanation. To investigate the role of the support on the resulting Ni structure and catalytic performance, catalysts were prepared by strong electrostatic adsorption, incipient wetness impregnation, and colloidal nanoparticle synthesis. The reactivity follows a volcano-type trend with Ni particle size on both TiO2 and CeO2 supports. To explain this trend, the role of the support on the reducibility of the Ni particles and distribution of basic sites on CO2 methanation activity was investigated. Using in situ infrared spectroscopy, we found that on TiO2 supported catalysts with larger Ni particles, CO2 methanation proceeds via a CO intermediate and the highest activity was observed when CO2 methanation occurs through both CO and carbonate intermediates. For catalysts with smaller particles on TiO2, however, no CO intermediates are observed, and catalytic activity is lower. For CeO2, the methanation also proceeds via a CO intermediate, though for larger Ni particles only CO species were observed. CeO2 without Ni can create surface formate species but has low reactivity towards methanation. In this investigation, we demonstrate a connection between the size of Ni particles, their corresponding adsorbed surface species, and their reactivity for CO2 methanation.</div>","PeriodicalId":66,"journal":{"name":"Catalysis Science & Technology","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141572840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A sugar-derived ligand for room temperature aerial oxidation or non-aqueous Markovnikov hydration of styrenes using a preformed or in situ generated Co complex† 使用预制或原位生成的 Co 配合物对苯乙烯进行室温气相氧化或非水马科夫尼科夫水合反应的糖源配体

IF 4.4 3区化学

Catalysis Science & Technology Pub Date : 2024-08-12 DOI: 10.1039/d4cy00522h

{"title":"A sugar-derived ligand for room temperature aerial oxidation or non-aqueous Markovnikov hydration of styrenes using a preformed or in situ generated Co complex†","authors":"","doi":"10.1039/d4cy00522h","DOIUrl":"10.1039/d4cy00522h","url":null,"abstract":"<div>The oxidation of styrenes to acetophenones is an industrially relevant transformation that has been traditionally conducted with the Wacker-type reaction using pure oxygen at high temperature and pressure using Pd–Cu catalysts. Herein, we report a Co(ii) complex of a salen appended l-diaminoribose-derived ligand that is catalytically active for the room temperature, selective aerial oxidation of styrenes to acetophenones. Further, the in situ generated Co(ii) complex (from a mixture of the salen appended l-diaminoribose-derived ligand and a Co(ii) salt) is also found to enable the catalysis. The oxidation is efficiently conducted in the presence of Et3SiH as a hydrogen atom transfer (HAT) agent and provides very high isolated yields (71–95%) of the acetophenones. Further, the HAT mediated transformation with NaBH4 also enables the non-aqueous, Markovnikov hydration of styrenes, providing the corresponding benzylic alcohols, exclusively as a single product in over 72–97% isolated yields via an oxidation–reduction mechanism. The methodologies provided very high exclusive yields of the products and were compatible with various substitutions on the aryl ring of the styrene. Detailed experimental and computational studies revealed a structural feature of the ligand that enabled the facile formation and stabilization of a pseudo-octahedral Co(iii) intermediate that facilitated the oxidation reaction.</div>","PeriodicalId":66,"journal":{"name":"Catalysis Science & Technology","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141502426","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Optimization of peptide foldamer-based artificial retro-aldolase† 优化基于肽折叠聚合物的人工逆醛酸酶

IF 4.4 3区化学

Catalysis Science & Technology Pub Date : 2024-08-12 DOI: 10.1039/d4cy00342j

引用次数: 0

Rational design of a bifunctional catalyst utilizing Mn-containing layered double oxide for the highly efficient oxidative cleavage of 1,2-diols† 利用含锰层状双氧化物合理设计双功能催化剂以高效氧化裂解 1,2-二醇

IF 4.4 3区化学

Catalysis Science & Technology Pub Date : 2024-08-12 DOI: 10.1039/d4cy00740a

引用次数: 0

Catalytic N2O decomposition in an electric field at low temperatures† 低温电场催化 N2O 分解

IF 4.4 3区化学

Catalysis Science & Technology Pub Date : 2024-08-12 DOI: 10.1039/d4cy00698d

引用次数: 0

Computational design of transition metal catalysts for hydrodefluorination of trifluoromethylarenes using hydrosilane† 利用氢硅烷对三氟甲基烯烃进行氢脱氟作用的过渡金属催化剂的计算设计

IF 4.4 3区化学

Catalysis Science & Technology Pub Date : 2024-08-12 DOI: 10.1039/d4cy00451e

{"title":"Computational design of transition metal catalysts for hydrodefluorination of trifluoromethylarenes using hydrosilane†","authors":"","doi":"10.1039/d4cy00451e","DOIUrl":"10.1039/d4cy00451e","url":null,"abstract":"<div>Expanding upon the initial use of nickel complexes to cleave aliphatic C–F bonds in the hydrodefluorination of trifluoromethylarenes, we employed linear free energy scaling relationships and molecular volcano plots to elucidate the impact of N-heterocyclic carbene and phosphine ligands, as well as metals and additives, on the energy span related to catalytic activity. Our findings revealed that multiple reference states must be essentially considered to fully describe the catalytic activity of the nickel complexes. We introduced the concept of “reference-generalized volcano plots” (RGVPs) as a tool aiding in the selection of the appropriate reference state to determine catalytic activity. Multivariate linear regression analysis using non-energetic descriptors allowed us to uncover the effects of steric and electronic properties on catalytic activity. Specifically, strong electron-donating and small- to moderate-sized ligands are identified as optimal for nickel catalysts. The RGVPs in combination with multivariate linear regression models based on steric and electronic molecular features provide chemical insights into catalytic activity and offer guidance for fine-tuning catalyst properties for hydrodefluorination.</div>","PeriodicalId":66,"journal":{"name":"Catalysis Science & Technology","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141572837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Increasing electrochemical chlorine selectivity over oxygen selectivity through the optimal weakening of oxygen bonds in transition metal-doped RuO2† 通过优化削弱过渡金属掺杂的 RuO2 中的氧键，提高电化学氯选择性而非氧选择性

IF 4.4 3区化学

Catalysis Science & Technology Pub Date : 2024-08-12 DOI: 10.1039/d4cy00448e

{"title":"Increasing electrochemical chlorine selectivity over oxygen selectivity through the optimal weakening of oxygen bonds in transition metal-doped RuO2†","authors":"","doi":"10.1039/d4cy00448e","DOIUrl":"10.1039/d4cy00448e","url":null,"abstract":"<div>The electrochemical chlorine evolution reaction (CER) is accompanied with the parasitic oxygen evolution reaction (OER) during acidic brine electrolysis, thereby reducing the efficiency of chlorine production. The guiding principles of enhancing the selectivity of the CER are investigated experimentally and computationally in RuO2 doped with first-row-transition elements. Computational studies suggest that low-valent dopants (e.g., Cu, Zn, Ni, Co, and Fe) tend to bulk segregate in adsorbate-rich conditions. Further, doping elements with higher d-electrons than Ru (e.g., Cu, Zn, Ni, and Co) in RuO2 tends to lower the binding strength of OER intermediates (e.g., HO–, O–, and HOO–), thereby increasing OER overpotential and providing more active sites for the CER. Doping has less effect on the binding strength of CER intermediates (ClO−) than bivalent OER intermediates (O–), resulting in higher CER selectivity. Computational studies suggest that Cu (d9)-doped RuO2 shows maximum CER selectivity, as corroborated by experiments with electrodeposited Cu-doped RuO2. Electrodeposited Cu-doped RuO2 (2% dopant concentration) shows a maximum CER selectivity of 95% in an acidic medium. However, doping a low valency aliovalent dopant and d-enriched metals also lowers the bridge-oxygen vacancy formation energy, thereby activating lattice-oxygen vacancy-aided water dissociation pathway in doped RuO2 and increasing the selectivity of the OER. This results in an optimum doping concentration for maximum CER selectivity, wherein the weakening of surface OER intermediates is achieved without affecting lattice oxygen bond strength. The present work offers insight into catalyst design considering CER and OER selectivity during electrochemical Cl2 production.</div>","PeriodicalId":66,"journal":{"name":"Catalysis Science & Technology","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141572838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A review on durability of key components of PEM fuel cells 关于 PEM 燃料电池关键部件耐久性的综述

IF 4.4 3区化学

Catalysis Science & Technology Pub Date : 2024-08-12 DOI: 10.1039/d4cy00351a

引用次数: 0

Broad-spectrum response of NiCo2O4–ZnIn2S4 p–n junction synergizing photothermal and photocatalytic effects for efficient H2 evolution† NiCo2O4-ZnIn2S4 p-n 结的广谱响应可协同光热和光催化效应，实现高效的 H2 演化

IF 4.4 3区化学

Catalysis Science & Technology Pub Date : 2024-08-12 DOI: 10.1039/d4cy00656a

{"title":"Broad-spectrum response of NiCo2O4–ZnIn2S4 p–n junction synergizing photothermal and photocatalytic effects for efficient H2 evolution†","authors":"","doi":"10.1039/d4cy00656a","DOIUrl":"10.1039/d4cy00656a","url":null,"abstract":"<div>In this study, we developed a novel approach by creating a flower-like p–n heterojunction, where NiCo2O4 (NCO) nanoparticles are deposited onto a flower-like hierarchical ZnIn2S4 (ZIS) microsphere, to facilitate photocatalytic H2 evolution from water. Theoretical calculations and experimental results underscore the synergistic effects of the heterojunction and photothermal properties in the NCO–ZIS composite, leading to a significant enhancement in photocatalytic activity. Detailed investigation of the photocatalytic mechanism elucidates how the heterojunction bolsters carrier separation and suppresses carrier recombination, while the photothermal effect broadens light absorption, elevates reaction temperature, accelerates carrier migration, and reduces activation energy. Therefore, the NCO–ZIS heterojunction exhibits exceptional hydrogen evolution performance, reaching 4507 μmol h−1 g−1, which surpasses ZIS alone by 5.04 times. This research lays the groundwork for designing highly active photothermal catalysts with broaden-spectrum solar energy utilization.</div>","PeriodicalId":66,"journal":{"name":"Catalysis Science & Technology","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141718051","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dispersion of Au entities over Mo2N and MoC for the low-temperature water–gas shift reaction† 金实体在 Mo2N 和 MoC 上的分散，用于低温水-气变换反应

IF 4.4 3区化学

Catalysis Science & Technology Pub Date : 2024-08-12 DOI: 10.1039/d4cy00489b

{"title":"Dispersion of Au entities over Mo2N and MoC for the low-temperature water–gas shift reaction†","authors":"","doi":"10.1039/d4cy00489b","DOIUrl":"10.1039/d4cy00489b","url":null,"abstract":"<div>Nitridation of an Au/MoO3 precursor, 8 nm Au particles dispersed over MoO3 nanobelts, by ammonia at 600 °C resulted in Au flat films of 4–27 nm wide over γ-Mo2N, while further carburization with a CH4/H2 mixture at 700 °C converted γ-Mo2N to α-MoC and simultaneously dispersed Au flat films into atomic layers and single-atoms. The Au/γ-Mo2N catalyst was nearly inert for the low-temperature water–gas shift reaction at 120 °C and it became appreciably active at 200 °C. By contrast, the Au/α-MoC catalyst was readily highly active at 120 °C and further, the specific activity was nearly tenfold at 200 °C. Structure analysis regarding the dispersion of Au entities and the structure properties of γ-Mo2N/α-MoC revealed that the support contributed significantly to the catalytic performance, in addition to the active Au species. The lower N vacancies of γ-Mo2N favored the dispersion of Au thin layers, but weakened the ability to dissociate H2O. Well-crystallized α-MoC anchored Au atomic layers and single-atoms and extended the Au–MoC interface, and thereby greatly facilitated H2O dissociation.</div>","PeriodicalId":66,"journal":{"name":"Catalysis Science & Technology","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141742200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0