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Recyclable Fenton-like catalyst based on zeolite Y supported ultrafine,highly-dispersed Fe_2O_3 nanoparticles for removal of organics under mild conditions

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Chinese Chemical Letters 2019年第2期30卷 324-330页

作者： xuanyu yang Xiaowei Cheng Ahmed A.Elzatahry Jinyang Chen Abdulaziz Alghamdi Yonghui Deng Department of Chemistry State Key Laboratory of Molecular Engineering of Polymers Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) Fudan University Materials Science and Technology Program College of Arts and Sciences Qatar University School of Environmental and Chemical Engineering Shanghai University Department of Chemistry College of Science King Saud University State Key Lab of Transducer Technology Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences

A versatile wet impregnation method was employed to conveniently and controllably deposit Fe_2O_3 nanoparticles on zeolites including commercial Y, mordenite and ZSM-5 with the similar framework Si/Al ratios and crystal sizes, respectively. The ultrafine Fe_2O_3 nanoparticles in size of 5 nm can be highly dispersed on zeolite Y matrix due to its much better wettability than ZSM-5 and mordenite. By using the obtained Fe_2O_3/zeolite composite as the heterogeneous Fenton-like catalysts, the degradation of phenol as a model reaction was systematically investigated, including the zeolite supports, particle size and dispersion of Fe_2O_3, and reaction conditions of H_2O_2 concentration, temperature, and pH value. The catalyst based on zeolite Y with Fe loading of 9% exhibited the best phenol degradation efficiency (> 90%)in neutral pH within 2 h. Its high catalytic activity in Fenton reaction can be attributed to the bifunctional properties of strong surface BrФnsted acidity and high reactivity of octahedral Fe^(3+) in the highlydispersed ultrafine Fe_2O_3 nanoparticles in size of 5 nm, which were the primary active centers to quickly decompose H_2O_2 into hydroxyl radicals. Since phenol degradation can be performed under mild conditions of ambient temperature (283-323 K) and a wide pH range (4.0-7.0), the catalysts can be easily recovered for recyclable use with stable degradation activity, which own the immense potential in deep treatment of organic pollutants in industrial wastewater.

关键词： Fenton-like reaction Zeolite Fe2O3 nanoparticles Highly-dispersed Phenol degradation

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Sulfonic acid-functionalized core-shell Fe_(3)O_(4)@carbon microspheres as magnetically recyclable solid acid catalysts

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Chinese Chemical Letters 2021年第6期32卷 2079-2085页

作者： Chenyi Yuan Xiqing Wang xuanyu yang Abdulaziz AAlghamdi Fahad AAlharthi Xiaowei Cheng Yonghui Deng Department of Chemistry State Key Laboratory of Molecular Engineering of PolymersShanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsFudan UniversityShanghai 200433China State Key Lab of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China Department of Chemistry College of ScienceKing Saud UniversityPO Box 2455Riyadh 11451Saudi Arabia

Green and recyclable solid acid catalysts are in urgent demand as a substitute for conventional liquid mineral *** this work,a series of novel sulfonic acid-functionalized core-shell Fe_(3)O_(4)@carbon microspheres(Fe_(3)O_(4)@C-SO_(3)H)have been designed and synthesized as an efficient and recyclable heterogeneous acid *** the synthesis,core-shell Fe_(3)O_(4)@RF(resorcinol-formaldehyde)microspheres with tunable shell thickness were achieved by interfacial polymerization on magnetic Fe_(3)O_(4)*** high-temperature carbonization,the microspheres were eventually treated by surface sulfonation,re sulting in Fe_(3)O_(4)@C-x-SO_(3)H(x stands for carbonization temperature)microspheres with abundant surface SO_(3)H *** obtained microspheres possess uniform core-shell structure,partially-graphitized carbon skeletons,superparamagnetic property,high magnetization saturation value of 10.6 emu/g,and rich SO_(3)H *** surface acid amounts can be adju sted in the range of 0.59-1.04 mmol/g via sulfonation treatment of carbon shells with different graphitization *** magnetic Fe_(3)O_(4)@C-x-SO_(3)H microspheres were utilized as a solid acid catalyst for the acetalization reaction between benzaldehyde and ethylene glycol,demonstrating high selectivity(97%)to benzaldehyde ethylene glycol *** importantly,by applying an external magnetic field,the catalysts can be easily separated from the heterogeneous reaction solutions,which later show well preserved catalytic activity even after 9 cycles,revealing good recyclability and high stability.

关键词： Core-shell Fe_(3)O_(4)@carbon Interfacial polymerization Magnetic microspheres Recyclability Solid acid catalyst Sulfonic acid-functionalization

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Amphiphilic block copolymers directed synthesis of mesoporous nickel-based oxides with bimodal mesopores and nanocrystal-assembled walls

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Chinese Chemical Letters 2019年第12期30卷 2003-2008页

作者： Yuan Ren xuanyu yang Xinran Zhou Wei Luo Yi Zhang Xiaowei Cheng Yonghui Deng Department of Chemistry State Key Laboratory of Molecular Engineering of PolymersShanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsiChEMFudan UniversityShanghai 200433China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China School of Materials Science and Energy Engineering Foshan UniversityFoshan 528000China

Mesoporous late-transition metal oxides have great potential in applications of energy,catalysis and chemical sensing due to their unique physical and chemical ***,their synthesis via the flexible and scalable soft-template method remain a great challenge,due to the weak organic-inorganic interaction between the frequently used surfactants(e.g.,Pluronic-type block copolymers) and metal oxide precursors,and the low crystallization temperature of metal *** this study,ordered mesoporous NiO with dual mesopores,high surface area and well-interconnected crystalline porous frameworks have been successfully synthesized via the facile solvent evaporation-induced co-assembly(EICA) method,by using lab-made amphiphilic diblock copolymer polystyrene-b-poly(4-vinylpyridine)(PS-b-P4 VP) as both the structure-directing agent(the soft template) and macromolecular chelating agents for nickel species,THF as the solvent,and nickel acetylacetonate(Ni(acac)2) as inorganic ***,by using Ni(acac)2 and Fe(acac)3 as the binary precursors,ordered mesoporous Fedoped NiO materials can be obtained,which have bimodal mesopores of large mesopores(32.5 nm) and secondary mesopores(4.0-11.5 nm) in the nanocrystal-assembled walls,high specific surface areas(~74.8 m^2/g) and large pore value(~0.167 cm^3/g).The obtained mesoporous Fe-doped NiO based gas sensor showed superior ethanol sensing performances with good sensitivity,high selectivity and fast response-recovery dynamics.

关键词： Block copolymer Co-assembly Metal oxides Mesoporous Gas sensing

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A facile construction of heterostructured ZnO/Co_(3)O_(4) mesoporous spheres and superior acetone sensing performance

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Chinese Chemical Letters 2021年第6期32卷 1998-2004页

作者： Mengli Lei Xinran Zhou Yidong Zou Junhao Ma Fahad AAlharthi Abdulaziz Alghamdi xuanyu yang Yonghui Deng Department of Chemistry State Key Laboratory of Molecular Engineering of PolymersShanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsiChEMFudan UniversityShanghai 200433China Institute of Translational Medicine Shanghai UniversityShanghai 200444China Department of Chemistry College of ScienceKing Saud UniversityP.O.Box 2455Riyadh 11451Saudi Arabia State Key Lab of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China

The rapid development of internet and internet of things brings new opportunities for the expansion of intelligent sensors,and acetone as a major disease detection indicator(i.e.,diabetes)making it become extremely important clinical ***,uniform mesoporous ZnO spheres were successfully synthesized via novel formaldehyde-assisted metal-ligand crosslinking *** order to adjust the pore structure of mesoporous ZnO,various mesoporous ZnO spheres were synthesized by changing weight percentage of Zn(NO_(3))_(2)·6 H_(2)O to tannic acid(TA).Moreover,highly active heterojunction mesoporous ZnO/Co_(3)O_(4)has been fabricated based on as-prepared ultra-small Co_(3)O_(4)nanocrystals(ca.3 nm)and mesoporous ZnO spheres by flexible impregnation *** from nano-size effect and synergistic effect of p-n heterojunction,mesoporous ZnO/Co_(3)O_(4)exhibited excellent acetone sensing performance with high selectivity,superior sensitivity and ***,5 wt%Co_(3)O_(4)embedded mesoporous ZnO sphere showed prominent acetone response(ca.46 for 50 ppm),which was about 11.5 times higher than that in pure ZnO sensing device,and it was also endowed high cyclic *** nanocrystals embedded hybrid material is expected to be used as promising efficient material in the field of catalysis and gas sensing.

关键词： Mesoporous materials P-N heterojunction Nanocrystal Nano-size effect Gas sensing

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Recent advance in synthesis and application of heteroatom zeolites

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Chinese Chemical Letters 2021年第1期32卷 328-338页

作者： Tingting Pang xuanyu yang Chenyi Yuan Ahmed A.Elzatahry Abdulaziz Alghamdi Xing He Xiaowei Cheng Yonghui Deng School of Materials Science and Engineering University of Shanghai for Science and TechnologyShanghai 200093China Department of Chemistry Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsFudan UniversityShanghai 200433China Materials Science and Technology Program College of Arts and SciencesQatar UniversityP.O.Box 2713DohaQatar Department of Chemistry College of ScienceKing Saud UniversityP.O.Box 2455Riyadh 11451Saudi Arabia State Key Lab of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China

Incorporation of heteroatoms into the framewo rk of zeolites has become a significant strategy to improve their performance in catalysis and adsorption,because the obtained heteroatom zeolites exhibit quite different properties from the conventional aluminosilicate zeolites in aspects of surface acidity,pore structures,particle size and so *** this review,the progress on the heteroatom zeolites including their synthesis and application is ***,the recent advance on the design and synthesis of different heteroatom zeolites is *** emphasis is placed on the introduction and comparison of three typical methods,including the direct synthesis,post synthesis and improved direct synthesis,for the traditional heteroatom zeolites(such as TS-1,Sn-MFI,Sn-β) and newly-reported heteroatom zeolites(such as W-MFI,Mo-MFI).According to their intrinsic characteristics,the application of heteroatom zeolites in diverse fields,such as production of fine chemicals,air pollution control and biomass conversion is then ***,the challenges and perspective on the future development of heteroatom zeolites in low-cost preparation and practical application are proposed.

关键词： Heteroatom zeolite Incorporation Tetrahedral coordination Research status Synthesis Application Prospective

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One-dimensional nanochains consisting of magnetic core and mesoporous aluminosilicate for use as efficient nanocatalysts

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Nano Research 2021年第11期14卷 4197-4203页

作者： Tong Zhang Qin Yue Panpan Pan Yuan Ren xuanyu yang Xiaowei Cheng Fahad A.Alharthi Abdulaziz A.Alghamdi Yonghui Deng Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu610051China Department of Chemistry State Key Laboratory of Molecular Engineering of PolymersFudan UniversityShanghai200433China State Key Laboratory of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai200050China Department of Chemistry College of ScienceKing Saud UniversityP.O.Box 2455Riyadh11451Saudi Arabia

Magnetic assembly at the nanoscale level brings potential possibilities in obtaining novel delicate nanostructures with unique physical, photonic or electronic properties. Interface surfactant micelle-directed assembly strategy holds great promising in fabricating ordered mesoporous materials with multifunctionality and pore parameter tunability. Combing these, herein, one-dimensional (1D) nanochains with well-aligned silica-coated magnetic particles as core and mesoporous aluminosilicate as shell are rational fabricated for the first time through magnetic field induced interface coassembly in biliquid system followed by the incorporation of Al species via in-situ chemical modification and transformation strategy. The obtained magnetic mesoporous aluminosilicate nanochains (MMAS-NCs) possess well-defined core-shell-shell sandwich nanostructure, tunable perpendicular mesopore channels in the shell (2.7–7.6 nm), high surface area (359 m^(2)·g^(-1)), abundant acidic sites, and superparamagnetism with a magnetization saturation of 13.8 emu·g^(-1). Thanks to the unique properties, the MMAS-NCs exhibit excellent performance in acting as magnetically recyclable superior solid acid catalysts and nanostirrers with high conversion of over 96.8%, selectivity of 95.0% in the deprotection reaction of benzaldehyde dimethylacetal to benzaldehyde. Moreover, MMAS-NCs exhibit an interesting pore size effect on the catalytic activity, namely, in the pore size range of 2–8 nm, the catalysts with larger pores show significantly enhanced catalytic activity due to the balanced mass transport and density of surface active sites.

关键词： nanochain mesoporous materials magnetic particle acid catalysis aluminosilicate

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Stepwise construction of Pt decorated oxygen-deficient mesoporous titania microspheres with core-shell structure and magnetic separability for efficient visible-light photocatalysis

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Chinese Chemical Letters 2020年第6期31卷 1598-1602页

作者： Zhijian Li Yao Wang Ahmed A.Elzatahry xuanyu yang Shouzhi Pu Wei Luo Xiaowei Cheng Yonghui Deng Department of Chemistry State Key Laboratory of Molecular Engineering of PolymersShanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsiChEMFudan University.Shanghai 200433China Jiangxi Key Laboratory of Organic Chemistry Jiangxi Science and Technology Normal UniversityNanchang 330013China Materials Science and Technology Program College of Arts and SciencesQatar UniversityDoha PO Box 2713Qatar State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China

Solid photocatalysts with high specific surface area,superior photoactivity and ease of recycling are highly desired in chemical process,water treatment and so *** this study,a facile stepwise sol-gel coating approach was utilized to synthesize Pt decorated oxygen-deficient mesoporous titania microspheres with core-shell structure and convenient magnetic separability(denoted as Fe3 O4@-SiO2@Pt/mTiO2-x).These photocatalysts consist of magnetic Fe3 O4 cores,nonporous insulating SiO2 middle layer and mesoporous anatase TiO2-x shell decorated by Pt nanoparticles(~3.5 nm)through wet impregnation and H2 *** a result of high activity of oxygen-deficiency of black TiO2-x by H2 reduction and efficient inhibition of electron-hole recombination by Pt nanoparticles,the rationally designed core-shell Fe3 O4@SiO2@Pt/mTiO2-x photocatalysts exhibit superior photocatalytic performance in rhodamine B(RhB)degradation under visible light irradiation,with more than 98%of RhB degraded within 50 *** core-shell structured photocatalysts show excellent recyclability under the assistance of magnetic separation with well-retained photocatalytic performance even after running five *** stepwise synthesis method paves the way for the rational design of a high-efficiency recyclable heterogeneous catalyst,including photocatalysts,for various applications.

关键词： Core-shell Mesoporous TiO2 Photocatalytic activity Magnetic recovery Visible light

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基于物理模拟试验的房柱式采空区变形特征研究

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煤炭科学技术 2024年第S01期52卷 30-36页

作者：刘亚明谷天峰王闫超杨烜宇山西省交通科技研发有限公司山西太原030032 黄土地区公路建设与养护技术交通行业重点实验室山西太原030032 西北大学地质学系大陆动力学国家重点实验室陕西西安710069

房柱式采空区具有采出率较小、留设煤柱较大的特点,其覆岩移动规律及地表变形规律与长壁式采空区差别较大,在煤柱失效情况下,地表会产生较大变形,威胁地面建构筑物的安全。为研究浅埋缓倾房柱式采空区覆岩和松散层的变形发育机制,基于PI... 详细信息

房柱式采空区具有采出率较小、留设煤柱较大的特点,其覆岩移动规律及地表变形规律与长壁式采空区差别较大,在煤柱失效情况下,地表会产生较大变形,威胁地面建构筑物的安全。为研究浅埋缓倾房柱式采空区覆岩和松散层的变形发育机制,基于PIV图像处理技术和模块化组装思路,在室内建立物理模型开展物理模拟试验,反演了房柱式采空区覆岩和松散层的变形发育过程,分析了房柱式开采和煤柱失稳条件下覆岩和松散层的变形机制。研究结果表明:①房柱式开采条件下,浅埋缓倾采空区覆岩变形可划分为3个区域:“条带状”变形区域、“梯形状”变形区域和“倒漏斗型”变形区域。松散层中的变形呈“梯形状”发育。②煤柱失稳条件下,覆岩变形规律保持不变,松散层变形特征由“梯形状”发育为“漏斗型”,且随着失稳煤柱的增加,松散层变形增大,“漏斗型”变形区域由中心向两端逐渐扩展。③房柱式开采结束后,采空区顶板受力可简化为承受均布荷载的简支梁,在煤柱持续失稳的情况下,覆岩和松散层的静载将导致采空区顶板达到极限平衡状态,顶板破坏模式为拉破断,在拉应力作用下产生裂缝,但顶板并未完全断裂,采空区顶板形成一种带裂缝的悬臂梁结构。浅埋缓倾房柱式采空区煤柱失稳对地表变形影响剧烈,松散层变形与覆岩变形基本处于同一量级。

关键词：房柱式采空区覆岩移动松散层地表变形

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基于能量守恒确定岩体结构面的抗剪强度

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岩石力学与工程学报 2020年第S01期39卷 2674-2682页

作者：杨烜宇王闫超李景皓张必昌山西省交通科技研发有限公司山西太原030000 黑龙江测绘地理信息局黑龙江哈尔滨150081

结构面是决定岩体力学性质的关键因素,确定其强度特性具有重要意义。基于能量守恒原理和莫尔–库仑强度准则,推导得出了岩体结构面抗剪强度的计算公式,通过室内直剪试验对其可行性进行验证,并与以往结构面强度准则进行对比,依据实际岩... 详细信息

结构面是决定岩体力学性质的关键因素,确定其强度特性具有重要意义。基于能量守恒原理和莫尔–库仑强度准则,推导得出了岩体结构面抗剪强度的计算公式,通过室内直剪试验对其可行性进行验证,并与以往结构面强度准则进行对比,依据实际岩体构造提出了结构面抗剪强度的测试方法。研究表明:(1)岩体结构面在剪切过程中发生了摩擦、剪断、剪胀/缩等行为,遵循能量守恒定律,利用能量守恒原理和莫尔–库仑强度准则可以计算得到结构面的抗剪强度。(2)结构面形态特征对其抗剪强度有重要的影响,主要表现为起伏度、起伏角以及凸起部分所占比例。二维条件下,以长度为衡量标准,三维条件下,需要考虑凹凸区域所占面积比例。(3)通过测量结构面形态和结构面壁的强度参数,简化测试方法,可以间接计算出其抗剪强度。研究结果对岩体结构面强度测试和岩体稳定性评价具有一定的意义。

关键词：岩石力学能量守恒结构面抗剪强度强度准则

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中国287个城市创新的空间分异与溢出效应

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经济地理 2023年第9期43卷 52-61页

作者：杨轩宇任胜钢靳海攀长沙师范学院经济管理学院湖南长沙410199 中南大学商学院湖南长沙410083

当前中国经济正处于由要素驱动向创新驱动转变阶段,城市作为创新的载体在其中发挥着重要作用。文章从实证角度研究中国城市层面较长序列的创新空间集聚与溢出效应。以2005—2020年中国地级及以上城市的创新水平为研究对象,采用变异系数... 详细信息

当前中国经济正处于由要素驱动向创新驱动转变阶段,城市作为创新的载体在其中发挥着重要作用。文章从实证角度研究中国城市层面较长序列的创新空间集聚与溢出效应。以2005—2020年中国地级及以上城市的创新水平为研究对象,采用变异系数、基尼系数、赫芬达尔指数和空间自相关指数等方法,考察中国城市创新的空间演化特征,并选择空间杜宾模型,探讨中国城市创新的影响因素,提出促进创新的政策建议。研究表明:(1)中国城市创新整体的空间差异和创新集中度呈下降趋势,南北方城市创新水平差异明显。(2)中国城市创新的空间Moran’s I值具有非线性距离衰减特征,表现为下降一段距离后略有回升之后继续下降;Moran’s I指数呈现出显著的高高—低低正向空间相关性,指数相对较低,但总体上呈增加趋势。(3)空间杜宾模型分析显示中国城市创新因子均具有显著正向影响,创新投入因子具有正向空间溢出效应、创新环境具有负向空间溢出效应,创新规模溢出效应尚不显著。据此,文章提出今后应加大城市创新投资和环境改善、推进城市间协同发展、促进城市创新集聚和扩散的发展策略。

关键词：创新发展创新水平南方和北方协同发展空间自相关空间集聚空间溢出

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