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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

Safety profile of two-dimensional Pd nanosheets for photothermal therapy and photoacoustic imaging

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Nano Research 2017年第4期10卷 1234-1248页

作者： Mei Chen Shuzhen Chen Chengyong He shiguang mo Xiaoyong Wang Gang Liu Nanfeng Zheng State Key Laboratory for Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materials and Engineering Research Center for Nano-Preparation Technology of Fujian Province College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China State Key Laboratory of molecular Vaccinology and molecular Diagnostics Center for Molecular Imaging and Translational Medicine School of Public Health Xiamen University Xiamen 361005 China Department of Microbiology and Immunology Xiamen Medical College Xiamen 361008 China

Two-dimensional （2D） nanosheets have emerged as an important class of nanomaterial with great potential in the field of biomedicines, particularly in cancer theranostics. However, owing to the lack of effective methods that synthesize uniform 2D nanomaterials with controlled size, systematic evaluation of size-dependent bio-behaviors of 2D nanomaterials is rarely reported. To the best of our knowledge, we are the first to report a systematic evaluation of the influence of size of 2D nanomaterials on their bio-behaviors. 2D Pd nanosheets with diameters ranging from 5 to 80 nm were synthesized and tested in cell and animal models to assess their size-dependent bioapplication, biodistribution, elimination, toxicity, and genomic gene expression profiles. Our results showed size significantly influences the biological behaviors of Pd nanosheets, including their photothermal and photoacoustic effects, pharmacokinetics, and toxicity. Compared to larger-sized Pd nanosheets, smaller-sized Pd nanosheets exhibited more advanced photoacoustic imaging and photothermal effects upon ultralow laser irradiation. moreover, in vivo results indicated that 5-nm Pd nanosheets escape from the reticuloendothelial system with a longer blood half-life and can be cleared by renal excretion, while Pd nanosheets with larger sizes mainly accumulate in the liver and spleen. The 30-nm Pd nanosheets exhibited the highest tumor accumulation. Although Pd nanosheets did not cause any appreciable toxicity at the cellular level, we observed slight lipid accumulation in the liver and inflammation in the spleen. Genomic gene expression analysis showed that 80-nm Pd nanosheets interacted with more cellular components and affected more biological processes in the liver, as compared to 5-nm Pd nanosheets. We believe this work will provide valuable information and insights into the clinical application of 2D Pd nanosheets as nanomedicines.

关键词： Pd nanosheets photothermal therapy photoacoustic imaging toxicity evaluation genomic gene expression

Effect of glutathione on in vivo biodistribution and clearance of surface-modified small Pd nanosheets

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Science China Chemistry 2015年第11期58卷 1753-1758页

作者： Yizhuan Huang Xiaolan Chen Saige Shi Mei Chen Shaoheng Tang shiguang mo Jingping Wei Nanfeng Zheng State Key Laboratory for Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry and Chemical EngineeringXiamen University

Plasmonic Pd nanosheets have been emerging as promising materials for application in near-infrared(NIR) photothermal therapy(PTT) of cancer. However, animal in mice studies indicated that the original synthesized poly(vinylpyrrolidone)(PVP)-protected small Pd nanosheets(Pd-PVP) and some further surface-modified small Pd nanosheets such as Pd-PEG(SH) easily accumulated in reticuloendothelial system(RES) organs(liver, spleen, etc.) and were difficult to be cleared from these organs quickly. In the work, we surprisingly found that glutathione(GSH) could promote the clearance of surface-modified small Pd nanosheets(e.g. Pd-PVP, Pd-PEG(SH) and Pd-GSH) from the RES organs efficiently. The effects of GSH on the biodistribution and clearance of different surface-modified Pd nanosheets were investigated. Our results indicated that these surface-modified Pd nanosheets with or without GSH added caused no morbidity at target primary organs, and GSH can promote the clearance of different surface-modified Pd nanosheets in the order of Pd-PVP≈Pd-PEG(SH)>Pd-GSH. This study suggests that glutathione could be an attractive reagent for promoting nanomaterials eliminated from the reticuloendothelial systems(RES).

关键词： noble metal nanomaterials glutathione biodistribution renal clearance

Air-promoted selective hydrogenation of phenol to cyclohexanone at low temperature over Pd-based nanocatalysts

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Science China Chemistry 2017年第11期60卷 1444-1449页

作者： Qing Guo shiguang mo Pengxin Liu Weidong Zheng Ruixuan Qin Chaofa Xu Youyunqi Wu Binghui Wu Nanfeng Zheng Department of Chemical and Biochemical Engineering National Engineering Laboratory for Green Chemical Productions of Alcohols-Ethers-EstersState Key Laboratory for Physical Chemistry of Solid SurfacesCollaborative Innovation Center of Chemistryfor Energy Materialsand Engineering Research Center for Nano-Preparation Technology of Fujian ProvinceCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

Attaining high activity with high selectivity at low temperature is challenging in the selective hydrogenation of phenol to cyclohexanone due to its high activation energy （Ea, 55-70 kJ/mol）. Here we report a simple and efficient strategy for phenol hydrogenation catalyzed by Pd in aqueous phase at 30 ℃ by introducing air to promote the catalysis. With the assistance of air, 〉99% conversion and 〉99% selectivity were achieved over Pd（111）/Al2O3 with an overall turnover frequency （TOF） of 621 h-1, -80 times greater than that of the state-of-art Pd catalyst at 30 ℃. Mechanism studies revealed that phenol was activated to generate phenoxyl radicals. The radicals were yielded from the reaction between phenol and hydroxyl radicals in the presence of hydrogen, oxygen and protic solvent on Pd. The phenoxyl pathway resulted in a low apparent Ea （8.2 kJ/mol） and thus high activity. more importantly, this strategy of activating substrate by air can be adapted to other Pd based catalysts, offering a new thinking for the rational design of cyclohexanone production in industry.

关键词： selective hydrogenation phenol palladium nanocatalysis radical

Non-contact biomimetic mechanism for selective hydrogenation of nitroaromatics on heterogeneous metal nanocatalysts

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Science China Chemistry 2022年第4期65卷 726-732页

作者： Wenting Zhou Laiyang Li Ruixuan Qin Jiaxin Zhu Shengjie Liu shiguang mo Zaifa Shi Huihuang Fang Pengpeng Ruan Jun Cheng Gang Fu 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 Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM) Xiamen 361005China

While the enzymatic reduction of unsaturated compounds usually has high specificity,highly selective reduction processes are hardly realized by heterogeneous industrial catalysts,which is critical for the green production of many fine ***,we report an unexpected discovery of a biomimetic behavior of dicyandiamide(DICY)-modified Pt nanocatalysts for the green hydrogenation of a wide range of *** demonstrate that the surface modification by DICY not only prevents the direct contact of nitroaromatic reactants with Pt surface but also induces an effective non-contact hydrogenation mechanism mediated by protons and *** such a process,the DICY layer serves as a“semi-permeable membrane”to allow the permeation of H_(2) molecules for being activated into electrons and protons at the Pt-DICY *** the generation of separated protons and electrons,the nitro group with strong electrophilic properties can be hydrogenated through the electron transfer followed by the proton transfer,which is facilitated by the hydrogen bonding network formed by protonated *** unique mechanism makes it highly directional toward the hydrogenation of nitro groups without side *** to its capability to largely eliminate the waste generation,the developed Pt-DICY catalysts have been successfully applied for the green industrial production of many important aniline intermediates.

关键词： hydrogenation catalysis nitroaromatics proton/electron separation non-contact hydrogenation biomimetic mechanism

Carbon monoxide Promotes the Catalytic Hydrogenation on Metal Cluster Catalysts

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Research 2020年第1期2020卷 702-710页

作者： Ruixuan Qin Pei Wang Pengxin Liu shiguang mo Yue Gong Liting Ren Chaofa Xu Kunlong Liu Lin Gu Gang Fu Nanfeng Zheng State Key Laboratory for Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materialsand National&Local Joint Engineering Research Center for Preparation Technology of NanomaterialsCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China College of Science Huazhong Agricultural UniversityWuhan 430070China Institute of Physics Chinese Academy of SciencesBeijing 100190China

Size effect plays a crucial role in catalytic *** highly dispersed ultrasmall clusters with a limited number of metal atoms are one candidate of the next generation catalysts that bridge the single-atom metal catalysts and metal ***,for the unfavorable electronic property and their interaction with the substrates,they usually exhibit sluggish *** advantage of the small size,their catalytic property would be mediated by surface binding *** combination of metal cluster coordination chemistry brings new *** poisoning is notorious for Pt group metal catalysts as the strong adsorption of CO would block the active *** this work,we will demonstrate that CO could serve as a promoter for the catalytic hydrogenation when ultrasmall Pd clusters are *** means of DFT calculations,we show that Pd_(n)(n=2-147)clusters display sluggish activity for hydrogenation due to the too strong binding of hydrogen atom and reaction intermediates thereon,whereas introducing CO would reduce the binding energies of vicinal sites,thus enhancing the hydrogenation ***,supported Pd_(2)CO catalysts are fabricated by depositing preestablished[Pd_(2)(μ-CO)_(2)Cl_(4)]2-clusters on oxides and demonstrated as an outstanding catalyst for the hydrogenation of *** promoting effect of CO is further verified experimentally by removing and reintroducing a proper amount of CO on the Pd cluster catalysts.

关键词： reaction. hydrogenation introducing

Prediction of Hot Deformation Behavior of 7mo Super Austenitic Stainless Steel Based on Back Propagation Neural Network

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材料导报 2024年第17期38卷 165-171页

作者： WANG Fan WANG Xitao XU shiguang HE Jinshan Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China Shandong Provincial Key Laboratory for High Strength Lightweight Metallic Materials Advanced Materials InstituteQilu University of Technology(Shandong Academy of Science)Jinan 250353China

The hot compression tests of 7mo super austenitic stainless(SASS)were conducted to obtain flow curves at the temperature of 1000-1200℃and strain rate of 0.001 s^(-1)to 1 s^(-1).To predict the non-linear hot deformation behaviors of the steel,back propagation-artificial neural network(BP-ANN)with 16×8×8 hidden layer neurons was *** predictability of the ANN model is evaluated according to the distribution of mean absolute error(MAE)and relative *** relative error of 85%data for the BP-ANN model is among±5%while only 42.5%data predicted by the Arrhenius constitutive equation is in this ***,at high strain rate and low temperature,the MAE of the ANN model is 2.49%,which has decreases for 18.78%,compared with conventional Arrhenius constitutive equation.

关键词： 7mo super austenitic stainless steel hot deformation behavior flow stress BP-ANN Arrhenius constitutive equation

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自还原法合成超小尺寸钯加氢催化剂

Science China Materials 2023年第7期66卷 2708-2714页

作者：莫世广荆文彤张伟杰刘锟隆吴炳辉秦瑞轩郑南峰 State Key Laboratory for Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materialsand Engineering Research Center for Nano-Preparation Technology of Fujian ProvinceCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Chemistry and Chemical Engineering Guangdong Laboratory Shantou 515031China Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen 361005China

负载型超小尺寸金属纳米颗粒在多相催化过程中表现出优异的催化性能.虽然已经发展了一些合成方法,但仍缺少便捷地合成超小尺寸催化剂的方法.通常情况下,加氢金属催化剂往往需要经过高温还原过程.但过量的还原剂,如H2,会导致金属纳米颗... 详细信息

负载型超小尺寸金属纳米颗粒在多相催化过程中表现出优异的催化性能.虽然已经发展了一些合成方法,但仍缺少便捷地合成超小尺寸催化剂的方法.通常情况下,加氢金属催化剂往往需要经过高温还原过程.但过量的还原剂,如H2,会导致金属纳米颗粒的聚集.本研究利用含有有机配体的钯前驱体合成了金属氧化物负载的超小尺寸钯催化剂.在惰性气氛下,通过简单的煅烧即可得到尺寸均一、超小的Pd纳米颗粒(~1 nm).有机配体中的-CHx基团与氧化物载体的表面氧物种反应促进了Pd物种的还原.同时,反应过程中原位产生的CO和氧空位稳定了超小尺寸纳米颗粒.该方法所制备得到的催化剂具有较高的抗烧结能力、优异和稳定的催化加氢反应性能.

关键词： self-reduction organic ligand stoichiometric reduction ultrafine nanoparticles catalytic hydrogenation

The Paleozoic Huoshenmiao iron skarn deposit in the Tongbai area of North Qinling Orogen,China:Insights from garnet U-Pb dating and geological constraints

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Science China Earth Sciences 2021年第12期64卷 2172-2189页

作者： Mingchun CHAI Hao HU Jianwei LI shiguang DU Linfeng HOU School of Earth Resources China University of GeosciencesWuhan430074China State Key Laboratory of Geological Process and Mineral Resources China University of GeosciencesWuhan430074China Pu’er Natural Resources and Planning Bureau Pu’er665000China

The Qinling Orogen is a composite orogenic belt that can be subdivided into the North and South Qinling,broadly separated by the Shangdan suture *** two orogenic belts were generated by subduction-collisional processes in the Early Paleozoic and Late Triassic,*** the Late Jurassic to Early Cretaceous,the eastern portion of the Qinling Orogen was tectonically reactivated due to westerly subduction of the Izanagi plate underneath the East China continental *** Qinling Orogen is well-endowed with numerous Au,mo,Ag-Pb-Zn deposits that predominantly formed in the Late Triassic to Early Cretaceous,with rare Paleozoic varieties *** this study,we present garnet and zircon U-Pb dating results to show that the Huoshenmiao iron skarn deposit in the Tongbai area of North Qinling orogenic belt formed in the Early Silurian and is genetically related to subduction-related *** Huoshenmiao deposit consists of lenticular and stratiform orebodies that contain massive or densely disseminated magnetite variably associated with garnet,diopside,epidote,hornblende,and *** from iron ores are andradite and grossular in composition(Ad_(83.1)Gr_(13.3)-Ad_(86.5)Gr_(10.2))and characterized by enrichment in light rare earth elements(ΣLREE=57.85-103.82 ppm)and depletion in heavy rare earth elements(ΣHREE=5.50-11.34 ppm),with significantly positive Eu and Ce anomalies(δEu of 1.09-1.89 andδCe of 1.39-1.69).These compositional signatures are distinctly different from those of garnets in the ore-hosting metamorphic rocks that are typically dominated by almandine,spessartine and grossular(Al_(47.4)Sp_(30.4)Gr_(13.8)-Al_(51.9)Sp_(24.8)Gr_(17.6)),depleted in LREE(0.14-0.69 ppm),enriched in HREE(95.68-841.60 ppm)and have pronounced negative Eu anomalies(δEu=0.24-0.51).In addition,garnets from iron ores of the Huoshenmiao deposit contain abundant daughter mineral-bearing,multiphase fluid inclusions,further confirming their hydrothermal origin

关键词： Huoshenmiao iron skarn deposit Tongbai area North Qinling orogenic belt Paleozoic metallogeny