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Supported Atomically Dispersed Pd Catalyzed Direct Alkoxylation and Allylic Alkylation

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Chinese Journal of chemistry 2024年第7期42卷 719-724页

作者： Ruixuan Qin Ziwen Chen Qingyuan Wu nanfeng zheng Pengxin Liu New Cornerstone Science laboratory State Key Laboratory for Physical Chemistry of Solid SurfacesCollaborative Innovation Center of Chemistry for Energy Materialsand National&Local Joint Engineering Research Center of Preparation Technology of NanomaterialsCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamenFujian 361005China Innovation Laboratry for Scences and Technoogies of Energy Materials of fujan Province(IKKM) Xiamen Fujian 361102China School of physical Science and Technology Shanghai Tech UniversityShanghai 201210China fujian key laboratory of Rare-earth functional Materials Fujian Shanhai Collaborative Innovation Center of Rare-earth Functional MaterialsLongyanFujian 366300China

A new approach to allylic alkylation is realized using an atomically dispersed palladium catalyst(Pd1/TiO2-EG).Unlike conventional methods that require derivation of substrates and utilization of additives,this method allows for direct allylic alkylation from allylic alcohols,producing H2O as the sole *** catalyst's high efficiency is attributed to the local hydrogen bonding at the or-ganic-inorganic interface(Pd-EG interface),facilitating hydroxyl group activation forη3π-allyl complex *** system demonstrates successful direct C—O and C—C coupling reactions with high selectivity,requiring no *** study highlights the potential of supported atomically dispersed catalysts for greener and more efficient catalysis,meanwhile,offers unique insights into the distinct behavior of atomically dispersed catalysts in comparison to homogeneous or nanoparticle-based catalysts.

关键词： Atomically dispersed catalyst Alkylation C—C coupling Organic-inorganic Interface Hydrogen bond Tsuji-Trost reaction Green catalysis

Interfacial oxidized Pd species dominate catalytic hydrogenation of polar unsaturated bonds

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Nano Research 2024年第1期17卷 228-234页

作者： Pengyao You Shaoqi Zhan Pengpeng Ruan Ruixuan Qin Shiguang Mo Yazhou Zhang Kunlong Liu Lansun zheng nanfeng zheng state key laboratory for physical chemistry of solid surfaces Collaborative Innovation Center of Chemistry for Energy Materialsand Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China department of chemistry BMCUppsala UniversityBMC Box 576Uppsala S-75123Sweden department of chemistry University of OxfordOxford OX13QZUK

The determination of catalytically active sites is crucial for the design of efficient and stable catalysts toward desired ***,the complexity of supported noble metal catalysts has led to controversy over the locations of catalytically active sites(e.g.,metal,support,and metal/support interface).Here we develop a structurally controllable catalyst system(Pd/SBA-15)to reveal the catalytic active sites for the selective hydrogenation of ketones to alcohol using acetophenone hydrogenation as model *** investigations demonstrated that unsupported Pd nanocrystals have no catalytic activity for acetophenone ***,oxidized Pd species were catalytically highly active for acetophenone *** catalytic activity decreased with the decreased oxidation state of *** work provides insights into the hydrogenation mechanism of ketones but also other unsaturated compounds containing polar bonds,e.g.,nitrobenzene,N-benzylidene-benzylamine,and carbon dioxide.

关键词： oxidized Pd metal/oxide interface constant particle size Pd/SBA-15 acetophenone hydrogenation

A simple solvothermal route towards the morphological control of ZnO and tuning of its optical and photocatalytic properties

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Science China chemistry 2010年第8期53卷 1711-1717页

作者： JIANG YaQi,LI fangfang,SUN Ran,XIE ZhaoXiong & zheng LanSun state key laboratory for physical chemistry of solid surfaces department of chemistry,College of chemistry and Chemical Engineering,Xiamen University,Xiamen 361005,China 1. state key laboratory for physical chemistry of solid surfaces department of chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China

ZnO nanoparticles with different morphologies were solvothermally synthesized by controlling the alkali (sodium hydroxide) concentration in an isopropanol *** products were characterized by means of powder X-ray diffraction,UV-visible absorption spectra,scanning electron microscopy,transmission electron microscopy,and selected area electron *** morphologies of the formed ZnO nanocrystals were dependent on the concentration of the alkali,and with increases of sodium hydroxide concentration,the ZnO nanocrystals evolved from rod to hexagonal bipyramid,and then to a flower-like *** flower-like nanostructure resulted from the etching of the hexagonal bipyramid by the excess *** photoluminescence and photocatalytic properties of the prepared ZnO were *** difference of green emission among the ZnO nanocrystals indicated that a higher sodium hydroxide concentration led to a higher level of *** size,the surface structure and defects in the ZnO nanocrystals affected its photo-degradation characteristics.

关键词： zinc oxide solvothermal method nanocrystal photoluminescence photocatalysis

Surface Ligand Evolution:Sulfur-Directed Covalent Bonding of PPh_(3) on Pd_(4)S with Improved Semi-hydrogenation of Terminal Alkynes

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Precision chemistry 2024年第5期2卷 200-207页

作者： Wentong Jing Shiguang Mo Weijie Zhang Wenting Zhou Kunlong Liu Jie Wei Ruixuan Qin nanfeng zheng New Cornerstone Science laboratory State Key Laboratory for Physical Chemistry of Solid SurfacesCollaborative Innovation Center of Chemistry for Energy Materialsand National&Local Joint Engineering Research Center of Preparation Technology of NanomaterialsCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China China Resources Cement Technology R&D(Guangxi)Co Ltd. Nanning 530008China Innovation laboratory for Sciences and Technologies of Energy Materials of fujian Province(IKKEM) Xiamen 361102China

Surface modification of metallic nanocatalysts with organic ligands has emerged as an effective strategy to enhance catalytic selectivity,although offten at the expense of catalytic *** this study,we demonstrate a compelling approach by surface modifying Pd2S nanocrystals with PPhz ligands,resulting in a catalyst with excellent catalytic activity and durable selectivity for the semi-hydrogenation of terminal *** and theoretical investigations reveal that the presence of S sites on the Pd surface directs PPh_(3) ligands to preferentially form covalent bonds with S,creating distinctive surface S=PPh_(3) *** configuration induces a partial positive charge on Pd,facilitating hydrogen transfer and thus promoting catalytic ***,the covalent bond between the ligand and catalyst surface forms a robust network,ensuring ligand stability and increasing the hydrogenation energy barrier of ***,the Pd_(4)S@PPhz catalyst exhibits an improved catalytic selectivity with durability in terminal alkyne *** study introduces an effective strategy for designing selective hydrogenation catalysts with an enhanced performance.

关键词： Pd nanocatalysts surface modification selective hydrogenation catalytic stability alkyne semi-hydrogenation

Color center-rich γ-AlOpromotes propane dehydrogenation

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Science China chemistry 2024年

作者： Yu Wang Xiang Wang Mengfei Qiao Qingyuan Wu Kunlong Liu Xiaodong Yi Ruixuan Qin Gang fu nanfeng zheng state key laboratory for physical chemistry of solid surfaces Collaborative Innovation Center of Chemistry for Energy Materialsand Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University key laboratory of the Ministry of Education for Advanced Catalysis Materials College of Chemistry and Material SciencesZhejiang Normal University Innovation laboratory for Sciences and Technologies of Energy Materials of fujian Province (IKKEM)

The PtSn/Al2O3catalyst is commonly used in commercial propane dehydrogenation （PDH） processes,but it faces challenges in the deactivation and periodic regeneration due to metal aggregation and coke deposition at high *** Al3+pentahas been proven to be beneficial for enhancing catalytic stability,bottom-up synthesis protocols usually restrict their ***,a facile post-treatment approach using acetic acid was applied to create color centers （electrons trapped within oxygen vacancies） on γ-Al3+***,the content of Alpentawas enriched to 18.3%.Then,the pre-established PtSn clusters were *** electrons facilitated the formation of ultrafine PtSn nanoparticles （～2 nm）,and the Al3+pentasites prevented the sintering of PtSn by constructing the strong Al3+penta–O–Sn ***,the catalytic durability of the catalyst prepared by conventional impregnation methods was remarkably extended from 186 h for the color center-free sample to 1,000 h using the HAc–*** facile post-modification was further successfully extended to commercial Al2O3pellets without altering their mechanical properties,highlighting its potential in industrial applications.

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Controlling the surface structures and tuning the related properties of nano/micro-structured crystallites

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Controlling the surface structures and tuning the related pr...

中国化学会第五届全国结构化学学术会议

作者： Zhao-Xiong Xie Lan-Sun zheng state key laboratory for physical chemistry of solid surfaces,department of chemistry,College of chemistry and Chemical Engineering,Xiamen University,Xiamen 361005,China.

Anisotropy is a basic property of single *** facets or surfaces have different geometric and electronic structures,dangling bonds *** dependent physical and chemical properties are very popular in *** examples,different crystal surfaces of Pt crystals exhibit totally different catalytic properties to the catalytic reaction of hexane in the excess H *** Pt(111)surfaces cause the aromatization reaction to produce benzene,while the

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A molten salt route to the synthesis of nano/micro-structured inorganic crystailites with all polar surfaces exposed

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A molten salt route to the synthesis of nano/micro-structure...

中国化学会第五届全国结构化学学术会议

作者： Tao Xu Xi Zhou Zhiyuan Jiang Zhaoxiong Xie Lansun zheng state key laboratory for physical chemistry of solid surfaces & department of chemistry,Xiamen University,Xiamen 361005,fujian,

＜正＞As has been well known,many ionic compounds can be described as a number of planes composed of cations and anions stacked *** positively-charged cations and negatively-charged anion planes give result to a normal dipole moment and spontaneous polarization along specific axis in these *** crystal growth,the polar surfaces

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Ag对钼磷酸盐催化剂丙烷氧化脱氢性能的影响

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石油化工 2002年第9期31卷 700-703页

作者：张昕万惠霖翁维正伊晓东清华大学化学系一碳化学与化工国家重点实验室北京100084 厦门大学化学系固体表面物理化学国家重点实验室福建厦门361005

借助催化剂性能评价、XRD、电导率测定、H2-TPR和XPS技术考察助剂Ag对钼磷酸催化剂丙烷氧化脱氢性能和催化剂性质的影响。结果表明,在Ag-Mo-P-O催化剂中形成Mo6++Ag0 Mo5+(Mo4+)+Ag+的氧化-还原循环,并且在催化剂中AgMoO2PO4和MoO3两相... 详细信息

借助催化剂性能评价、XRD、电导率测定、H2-TPR和XPS技术考察助剂Ag对钼磷酸催化剂丙烷氧化脱氢性能和催化剂性质的影响。结果表明,在Ag-Mo-P-O催化剂中形成Mo6++Ag0 Mo5+(Mo4+)+Ag+的氧化-还原循环,并且在催化剂中AgMoO2PO4和MoO3两相之间存在由"一致性界面"引起的协同效应,提高了催化剂的氧化还原性。在催化剂中添加适量的Ag,有助于获得高丙烯选择性和高收率。

关键词：银钼磷酸盐催化剂丙烷氧化脱氢性能影响丙烯助剂

Shape Evolution of Au-Pd Alloy Nanocrystals from Rhombic Dodecahedron to Trisoctahedron and Hexoctahedron

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Shape Evolution of Au-Pd Alloy Nanocrystals from Rhombic Dod...

中国化学会第六届全国结构化学学术会议

作者： Jia-Wei Zhang,Zhao-Xiong Xie~*,Lan-Sun zheng state key laboratory of physical chemistry of solid surfaces,department of chemistry,college of chemistry and chemical engineering,Xiamen University,Xiamen,361005,China

＜正＞The surface structure controlled synthesis of noble metal nanocrystals（NCs） bounded by high-index facets has become a hot topic due to their potential of significantly improving the catalytic performance in the catalytic *** study reports the preparation of monodisperse Au-Pd alloy NCs with systematic shape evolution from rhombic dodecahedral（RD） to trisoctahedral（TOH）,and hexoctahedral

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