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Synthesis of silica particles with lamellar and wormhole-like bi-modal mesopores using anionic surfactant as the template

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Science China Chemistry 2009年第9期52卷 1423-1426页

作者： HE WenChao WANG JinGui chen tiehong Institute of New Catalytic Materials Science Key Laboratory of Energy-Material Chemistry(Tianjin)and Engineering Research Center of Energy Storage&Conversion(MOE)College of ChemistryNankai UniversityTianjin 300071China

Silica particles with lamellar and wormhole-like bi-modal mesopores have been synthesized using anionic surfactant (N-lauroylsarcosine sodium) as the template. The particles with diameters of 300―500 nm possess bi-modal mesopores with pore sizes of 3 nm and 12 nm, which were ascribed to the disordered wormhole-like mesophase and lamellar mesophase, respectively. The BET surface area of the particles was 536 m2/g and the pore volume was 0.83 cm3/g. The lamellar mesophase and cylindrical mesophase were formed due to the co-assembly of the anionic surfactant and its protonized polar oil.

关键词： lamellar structure anionic surfactant mesoporous silica morphology N-lauroylsarcosine sodium

Hierarchically porous zeolites synthesized with carbon materials as templates

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Frontiers of Chemical Science and Engineering 2021年第6期15卷 1444-1461页

作者： Huan Wang Guo Du Jiaqing Jia Shaohua chen Zhipeng Su Rui chen tiehong chen Institute of New Catalytic Materials Science School of Materials Science and EngineeringKey Laboratory of Advanced Energy Materials Chemistry(MOE)Nankai UniversityTianjin300350China

Hierarchically porous zeolites are promising candidates in catalytic conversion of relatively bulky molecules,and their syntheses have attracted significant *** both industrial and scientific perspectives,different carbon materials have been widely employed as hard templates for the preparation of hierarchically porous zeolites during the past two *** this review,the progress in synthetic strategies using carbon materials as templates is comprehensively *** on the affinity between the carbon templates and zeolite precursors,the substantial strategies for synthesizing hierarchical zeolites are introduced in direct templates and indirect *** templates methods,by which the carbon materials are directly mixed with precursors gel as hard templates,are first ***,we discuss the indirect templates method(crystallization of carbon-silica composites),by which the carbon is produced by in situ pyrolysis of organic-inorganic *** addition,the technique of encapsulating metal species into zeolites crystals with the assistance of carbon templates is also *** the conclusion part,the factors affecting the synthesis of carbon-templated hierarchically porous zeolites are *** review is expected to attract interest in the synthesis strategies of hierarchically porous zeolites,especially cost-effective and large-scale production methodologies,which are essential to the industrial application of hierarchical zeolites.

关键词： hierarchical zeolites carbon materials direct templates indirect templates carbon-silica composites

Fe/Co-based nanoparticles encapsulated in heteroatom-doped carbon electrocatalysts for oxygen reduction reaction

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Science China Materials 2019年第11期62卷 1626-1641页

作者： Baoxia Ni Luming Wu Rui chen chengxiang Shi tiehong chen Institute of New Catalytic Materials Science School of Materials Science and Engineering Key Laboratory of Advanced Energy Materials Chemistry (MOE) Nankai University

It is crucial to develop low-cost and highly efficient catalysts for oxygen reduction reaction(ORR)which is the key process in electrochemical energy conversion and storage *** metal-based nanoparticles/carbon materials are an important class of non-noble metal catalysts that have attracted considerable research *** topic of this review is mainly focused on carbon encapsulated Fe/Cobased nanoparticles catalysts for ORR,and these catalysts are summarized in categories of metals,oxides,carbides,phosphides,sulfides and hybrid *** structures and morphologies of the carbon matrix as well as compositions of nanoparticles have great influence on the catalytic *** catalysts display excellent ORR activity and stability in alkaline media but only a few are efficient in acidic *** addition,challenges and further strategies on the development of this type of carbon encapsulated nanoparticles catalysts are also proposed.

关键词： Fe/Co based nanoparticles encapsulation carbon oxygen reduction reaction

Encapsulated FeP nanoparticles with in-situ formed P-doped graphene layers:Boosting activity in oxygen reduction reaction

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Science China Materials 2021年第5期64卷 1159-1172页

作者： Baoxia Ni Rui chen Luming Wu Pingchuan Sun tiehong chen Institute of New Catalytic Materials Science School of Materials Science and EngineeringKey Laboratory of Advanced Energy Materials Chemistry(MOE)Nankai UniversityTianjin 300350China Key Laboratory of Functional Polymer Materials(MOE) College of ChemistryNankai UniversityTianjin 300071China

Nonprecious metal-based oxygen reduction reaction(ORR)electrocatalysts with high efficiency in both alkaline and acidic media are being intensively studied for the purpose of replacing expensive Pt-based catalysts;however,it is still a challenge to achieve superior ORR performances,especially in acidic ***,by pyrolysis of mixed precursors of diammonium phosphate,melamine and hemin,we prepared a nanocomposite catalyst(denoted as FeP@PGL)composed of nitrogen-doped carbon nanosheets with embedded FeP nanoparticles(NPs),which were encapsulated by in-situ formed phosphorus-doped graphene *** is found that phosphorous was preferentially doped in the coating layers on FeP NPs,instead of in the carbon *** FeP@PGL catalyst exhibited excellent ORR performance,with the onset and half-wave potential up to 1.01 and 0.90 V *** reversible hydrogen electrode(RHE)in alkaline media,and0.95 and 0.81 V *** in acidic media,*** thorough microscopy and spectroscopy characterizations,the interfacial charge transfer between the encapsulated FeP NPs and P-doped graphene layers was identified,and the local work function of the catalyst surface was also reduced by the interfacial *** interfacial synergy between the encapsulated FeP and phosphorus-doped graphene layers was essential to enhance the ORR *** study not only demonstrates the promising ORR properties of the encapsulated-FeP-based nanocomposite catalyst,but also provides direct evidence of the interfacial charge transfer effect and its role in ORR process.

关键词： FeP encapsulation phosphorus-doped graphene layers charge transfer oxygen reduction reaction

A durable Ni/La-Y catalyst for efficient hydrogenation of γ-valerolactone into pentanoic biofuels

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Journal of Energy Chemistry 2022年第7期31卷 347-355,I0009页

作者： Jiang He Lu Lin Meng Liu Caixia Miao Zhijie Wu Rui chen Shaohua chen tiehong chen Yang Su Tao Zhang Wenhao Luo CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Heavy Oil Processing and Key Laboratory of Catalysis of CNPC China University of PetroleumBeijing 102249China Key Laboratory of Advanced Energy Materials Chemistry Nankai UniversityTianjin 300350China

Zeolite-supported metal catalysts containing hydrogenation centers and acid sites are promising in the chemoselective hydrogenation of biomass platform molecules into value-added chemicals and *** primary challenge of employing such bifunctional catalysts for biomass conversion lies in catalyst stability in the liquid phase under harsh conditions. Herein, we have prepared a Ni/La-Y nanocatalyst via an improved wet impregnation method. Compared with Ni nanoparticles on H-Y, La addition shows a significantly enhanced stability and performance in the continuous liquid-phase hydrogenation of γ-valerolactone(GVL) into ethyl pentanoate(EP) at 200 ℃ for 1000 h. Complementary characterization studies reveal that La addition in the metal/zeolite catalyst not only efficiently modulates the acid property of the zeolite to alleviate coke formation, but also suppresses zeolite dealumination and metal agglomeration and leaching upon catalysis over a 1000 h period. These findings provide an efficient approach for improving the stability of zeolite-supported bifunctional catalysts, leading to potential application in hydrogen-assisted biomass valorization under the liquid-phase conditions.

关键词： Nickel Zeolite Hydrogenation Stability Biofuel

Hierarchically porous Fe/N/S/C nanospheres with high-content of Fe-Nx for enhanced ORR and Zn-air battery performance

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Green Energy & Environment 2023年第6期8卷 1693-1702页

作者： Luming Wu Ruge Zhao Guo Du Huan Wang Machuan Hou Wei Zhang Pingchuan Sun tiehong chen Institute of New Catalytic Materials Science School of Materials Science and EngineeringNankai UniversityTianjin300350China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Renewable Energy Conversion and Storage CenterCollege of ChemistryNankai UniversityTianjin300071China Haihe Laboratory of Sustainable Chemical Transformations Tianjin300192China Key Laboratory of Functional Polymer Materials(MOE) College of ChemistryNankai UniversityTianjin300071China

Heteroatom-doped carbon-based transition-metal single-atom catalysts(SACs) are promising electrocatalysts for oxygen reduction reaction(ORR). Herein, with the aid of hierarchically porous silica as hard template, a facile and general melting perfusion and mesopore-confined pyrolysis method was reported to prepare single-atomic Fe/N–S-doped carbon catalyst(FeNx/NC-S) with hierarchically porous structure and well-defined morphology. The FeNx/NC-S exhibited excellent ORR activity with a half-wave potential(E_(1/2)) of 0.92 V, and a lower overpotential of 320 mV at a current density of 10 mA cm^(-2)for OER under alkaline condition. The remarkable electrocatalysis performance can be attributed to the hierarchically porous carbon nanospheres with S doping and high content of Fe-Nx sites(up to 3.7 wt% of Fe), resulting from the nano-confinement effect of the hierarchically porous silica spheres(NKM-5) during the pyrolysis process. The rechargeable Zn-air battery with FeNx/NC-S as a cathode catalyst demonstrated a superior power density of 194.5 mW cm-2charge–discharge stability. This work highlights a new avenue to design advanced SACs for efficient sustainable energy storage and conversion.

关键词： Melting perfusion Nano-confined pyrolysis Hierarchically porous High content of Fe-Nx sites Sulfur doping Oxygen reduction reaction

Template-free fabrication of fractal porous Y2O3 monolithic foam and its functional modification by Ni-doping

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Science China Materials 2020年第9期63卷 1842-1847页

作者： Rui chen Wenqian Xu Sanjaya D.Senanayake José A.Rodriguez Jingguang G.chen tiehong chen School of Materials Science and Engineering Key Laboratory of Advanced Energy Materials Chemistry(MOE)Collaborative Innovation Center of Chemical Science and Engineering(Tianjin)Nankai UniversityTianjin 300350China X-ray Science Division Advanced Photon SourceArgonne National LaboratoryArgonne 60439USA Chemistry Division Brookhaven National LaboratoryUptonNew York 11973USA

Hierarchically porous materials have attracted growing interest due to their great potential in catalysis,separation,and biomedical systems[1–6].Tremendous efforts have been devoted to the rational design and synthesis of advanced porous materials with fascinating synergetic properties or multifunctions originating from their special porous structures[7–13].Generally,hierarchical porous structures can be created through hard or soft templates,or combination of soft and hard templates[14,15].However,disadvantages related to high cost or tedious synthetic steps have been impeding the scale-up of these synthesis routes for practical applications.

关键词：混合氧化物配位聚合微米孔纳米孔尺度范围纳米晶粒分形结构金属阳离子

SYNTHESIS OF NANOPOROUS SILICA WITH INTERIOR COMPOSITE CELLS WITH SYNTHETIC BLOCK COPOLYPEPTIDE AS TEMPLATE

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Chinese Science Bulletin 2006年第4期51卷 493-497页

作者： LIU Yuping ZHOU Huijing SHEN Zhurui LI Liying ZHOU Xingdi SUN Pingchuan YUAN Zhongyong chen tiehong LI Baohui DING Datong Department of Materials Chemistry Key Laboratory of FunctionalPolymer Materials of Ministry of Education College of ChemistryNankai University Tianjin 300071 China College of Physics Nankai University Tianjin 300071 China

Nanoporous silica with unusual interior composite cells was synthesized with synthetic block copolypeptide Phe20-b-PBLG50 as template for the first time. Anilino-methyl triethoxy silane (AMTS) was used as an intermedium to interact with block co-polypeptide Phe20-b-PBLG50 through π-π interaction between the phenyl groups of block copolypeptide and those of AMTS. Meanwhile, AMTS co-condenses together with tetraethoxylsilane (TEOS) after hy-drolysis. The structure of composite vesicles due to the self-assembly of block copolypeptide in the or-ganic solvent was immobilized and transcribed by the formation of silica. The formation of nanopores could be ascribed to the secondary structure of block co-polypeptide and small molecular amine. Our results provide a new avenue to synthesize porous oxide materials with novel interior structures templated by the copolypeptide self-assembly under ambient con-ditions.

关键词：纳米多孔硅合成模板法 π-π交互作用自组装多肽

O-37-Ultrasound-assisted Synthesis of Hollow Mesoporous Silica with Controlled Mesostructure

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O-37-Ultrasound-assisted Synthesis of Hollow Mesoporous Sili...