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Confining carbon dots in amino-functionalized mesoporous silica:n→π^(*) interaction triggered deep-red solid-state fluorescence

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Nano Research 2023年第3期16卷 4170-4177页

作者： Hongyue Zhang Qingyi Li Shuo Wang Xiaowei yu Bolun Wang Guangrui Chen Li Ren Jiyang Li Mingxing Jin jihong yu State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012China Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China Key Laboratory for Molecular Enzymology and Engineering The Ministry of EducationJilin UniversityChangchun 130012China International Center of Future Science Jilin UniversityChangchun 130012China

Deep-red and near-infrared emissive carbon dots(CDs)are highly desired for bioimaging,especially in deep tissue imaging,but they are extremely rare and the known ones usually suffer from low-efficient fluorescence in water and aggregation-induced fluorescence quenching in solid *** this work,CDs with intriguing solvent-dependent and two-photon fluorescence emissions have been prepared by a facile solvothermal *** characterizations reveal that there is an n→π*interaction between the carboxyl functional groups on CDs and the electron donor groups in solvent,which leads to the increase of energy density of CDs and the decrease of energy level,resulting in the red shift of luminescence with enhanced electron donating ability of *** by this finding,mesoporous silica nanoparticles(MSNs)with suitable pore size and low biological toxicity are modified by amino groups to confine CDs,thus the deep-red fluorescence emission is achieved both in solid state and in water facilitated by the n→π*interaction of *** as-prepared CDs@EDA-MSN composite exhibits high-efficient fluorescence with 650 nm wavelength,low toxicity,and good biocompatibility,which endow them a promising application in bio-imaging.

关键词： carbon dots mesoporous silica deep-red fluorescence donor-acceptor modulation bioimaging

La ions-enhanced NH_(3)-SCR performance over Cu-SSZ-13 catalysts

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Nano Research 2023年第10期16卷 12126-12133页

作者： Mengyang Chen Wenru Zhao Yingzhen Wei Jinfeng Han Junyan Li Chang Sun Donghai Mei jihong yu State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012China School of Materials Science and Engineering Tiangong UniversityTianjin 300387China International Center of Future Science Jilin UniversityChangchun 130012China

Lanthanum(La)ions are generally recognized to cause a decline of the catalytic performance for Cu-SSZ-13 zeolite in the selective catalytic reduction of NO_(x)with NH_(3)(NH_(3)-SCR).Herein,we demonstrate that the NH_(3)-SCR performance and hydrothermal stability of Cu-La-SSZ-13 zeolites can be enhanced with the incorporation of a small amount of La *** incorporation of La ions into SSZ-13 favors more Z_(2)Cu^(2+)ions at six-membered rings(6MRs),which results in higher hydrothermal stability of Cu-La-SSZ-13 than that of *** NO conversion of Cu-La-SSZ-13 achieves 5%–10%higher than that of Cu-SSZ-13 at the temperature range of 400–550℃ after hydrothermal *** introducing excess amount of La ions in SSZ-13 may cause the formation of inactive CuO_(x),leading to the decrease of catalytic activity and hydrothermal ***,the low-temperature activity of Cu-SSZ-13 with a low Cu content(≤2 wt.%)can be boosted by the introduction of La ions,which is largely due to the improved redox ability of Cu active sites modified by La *** functional theory(DFT)calculations indicate that La ions prefer to locate at eight-membered rings(8MRs)and thus promoting the formation of more Z_(2)Cu^(2+)***,the existence of La ions in SSZ-13 inhibits the dealumination process and the transformation from Z_(2)Cu^(2+)to CuO_(x),resulting in its enhanced hydrothermal *** present work sheds a new insight into the regulation of secondary metal cations for promoting high NH_(3)-SCR performance over Cu-SSZ-13 zeolite catalysts.

关键词： zeolite bimetallic catalyst Cu-SSZ-13 lanthanum ammonia selective catalytic reduction(NH_(3)-SCR)

Themed Issue Dedicated to Professor Ruren Xu on the Occasion of his 90th Birthday

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Chemical Research in Chinese Universities 2022年第1期38卷 I0001-I0004页

作者： yu jihong ZHAO Dongyuan YAN Wenfu Jilin University Fudan University

Professor Ruren Xu of Jilin University is a leader in the Chinese,Asian and worldwide zeolite communities as well as the founder of the inorganic synthesis discipline in China,the first proposer of the scientific system of modem inorganic chemistry in the *** has been working at Jilin University for 70 years since *** was elected a member of the Chinese Academy of Sciences in 1991 and a Fellow of the Academy of Sciences for the Developing World(TWAS)in *** served as an associate editor of Chemical Journal of Chinese Universities and Chemical Research in Chinese Universities for over 20 *** was a member of the International Advisory Board of Microporous Materials(1992-1997)and Microporous and Mesoporous Materials(since 1998),a Councilor of the International Zeolite Association(IZA,1998-2004),the chairman of the 15th International Zeolite Conference held in Beijing(2007),and the honoraiy chairman of the first Europe-Asia Zeolite Conference(EAZC)in Macao(2013).

关键词： inorganic porous zeolite

Special Issue for the 70^(th) Anniversary of the Discipline of Chemistry at Jilin University

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Chemical Research in Chinese Universities 2022年第3期38卷 I0001-I0006页

作者： yu jihong LI Yi LU Zhongyuan LIU Kun Jilin University

This year the Discipline of Chemistry at Jilin University will celebrate its 70^(th)anniversary in *** 1952,the Discipline of Chemistry at Jilin University was founded by *** Liusheng(academician),*** Auchin(academician),*** Shizhi,and *** Weisun and many other prestigious *** in the spirit of collaboration and innovation,the Discipline of Chemistry is now internationally renowned for its excellence and innovation in both fundamental research and student education.

关键词： Jilin anniversary

Topology optimization of chiral metamaterials with application to underwater sound insulation

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Applied Mathematics and Mechanics(English Edition) 2024年第7期45卷 1119-1138页

作者： Chao WANG Honggang ZHAO Yang WANG Jie ZHONG Dianlong yu jihong WEN Laboratory of Science and Technology on Integrated Logistics Support National University of Defense Technology

Chiral metamaterials have been proven to possess many appealing mechanical phenomena, such as negative Poisson's ratio, high-impact resistance, and energy absorption. This work extends the applications of chiral metamaterials to underwater sound insulation. Various chiral metamaterials with low acoustic impedance and proper stiffness are inversely designed using the topology optimization scheme. Low acoustic impedance enables the metamaterials to have a high and broadband sound transmission loss(STL), while proper stiffness guarantees its robust acoustic performance under a hydrostatic pressure. As proof-of-concept demonstrations, two specimens are fabricated and tested in a water-filled impedance tube. Experimental results show that, on average, over 95% incident sound energy can be isolated by the specimens in a broad frequency range from 1 k Hz to 5 k Hz, while the sound insulation performance keeps stable under a certain hydrostatic pressure. This work may provide new insights for chiral metamaterials into the underwater applications with sound insulation.

关键词： chiral metamaterial topology optimization underwater sound insulation low acoustic impedance sound transmission loss (STL) O427.5 74J20

The state-of-the-art synthetic strategies for SAPO-34 zeolite catalysts in methanol-to-olefin conversion

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National Science Review 2018年第4期5卷 542-558页

作者： Qiming Sun Zaiku Xie jihong yu State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of Chemistry Jilin University International Center of Future Science Jilin University SINOPEC Corporation Science and Technology Development Department

Methanol-to-olefin(MTO)conversion has proven to be one of the most successful non-petrochemical routes for producing light ***(SAPO)zeolite SAPO-34 is one of the best industrial catalysts for MTO conversion,but suffers from rapid deactivation due to the inherent diffusion bottleneck limited by the narrow eight-ring pore *** improve the MTO performance,considerable synthetic efforts have been devoted to decrease the crystal size of zeolites or introduce secondary larger pores in zeolite crystals to form hierarchical *** review mainly focuses on presenting the state-of-the-art synthetic strategies for nanosized and hierarchical SAPO-34 catalysts with excellent MTO ***,the industrialization of SAPO-34 catalysts for the MTO reaction,and some current problems and future prospects for the synthesis of SAPO-34 catalysts,are also pointed *** expect that this review can not only shed some light on the preparation of SAPO-34 catalysts,but also stimulate the future development of high-performance SAPO-34 catalysts to meet the increasing demands of the chemical industry.

关键词： methanol-to-olefin zeolites SAPO-34 hierarchically porous structure nanocrystals heterogeneous catalysis

Entropy-driven self-assembly of chiral nematic liquid crystalline phases of AgNR@Cu20 hyper branched coaxial nanorods and thickness-dependent handedness transition

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Nano Research 2018年第2期11卷 1018-1028页

作者： Guiqing Cheng yu Wang Kun Liu jihong yu State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of Chemistry Jilin University Changchun China State Key Laboratory of Supramolecular Structure and Materials College of Chemistry Jilin University Changchun China

The chiral nematic liquid crystalline phase （CNLCP） of noble metal nanorods induces a strong chiroptical response due to their intrinsic physical and chemical properties. Here, we demonstrate that the formation of CNLCP of Ag nanorods （AgNRs） originates from their bent-shape and is the result of purely entropic effects. The chirality of the liquid crystalline phase of AgNR@Cu20 hyper branched coaxial nanorods （HBCNRs） can be switched from left-handed to right-handed by increasing Cu20 thickness. It is proposed that the increase of coating thickness decreases the curvature of nanorods, which induces variation of the twist constant （/〈2） and bend elastic constant （K3）. The increased thickness also changes the direction of director with respect to the helical axis. In addition, hydrogen bonds can break the CNLCP, which can be attributed to their stronger effection compared to van der Waals forces and electrostatic interactions. In contrast to the variation of coating thickness, the surface morpholog~ constituents of the hybrid building blocks and polarity of the solvents do not play important roles in the handedness transition of the liquid crystalline phase. Furthermore, the results presented here give insight into the structure-property relationship and our strategy provides guidance for the synthesis of other inorganic chiral suDrastructures driven bv entroDic effects.

关键词： chirality circular dichroism Ag nanorod(AgNR)@Cu2O liquid crystals chiroptical response

Layer-by-Layer Approach to Superhydrophobic Zeolite Antireflective Coatings

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Chinese Journal of Chemistry 2018年第1期36卷 51-54页

作者： Jianan Zhang jihong yu State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of Chemistry Jilin University Changchun Jilin 130012 China College of Materials Science and Engineering Zhengzhou University Zhengzhou Henan 450001 China International Center of Future Science Jilin University Changchun Jilin 130012 China

Antireflection surfaces and coatings have attracted considerable interests because they can maximize light transmittance of the substrates. In this work, zeolite antireflective （ZAR） coatings are prepared via layer-by-layer （LBL） assembly of MFI-type zeolite silicalite-1 and polyelectrolyte. A micro- and macroporous hierarchical structure was obtained which contributes to the antireflective property of the zeolite coatings. The light transmittance of the coating on quartz can achieve as high as 99.3% at 650 nm. Furthermore, a superh~/drophobic ZAR coating can be obtained by chemical modification with 1H,1H,2H,2H-perfluorooctyl-triethoxysilane. This work demonstrates that zeolites are excellent candidates as high transparent superhydrophobic coatings.

关键词： zeolite MFI coating layer-by-layer assembly antireflection superhydrophobicity

Unraveling templated-regulated distribution of isolated SiO4 tetrahedra in silicoaluminophosphate zeolites with high-throughput computations

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National Science Review 2022年第9期9卷 19-27页

作者： Yan Li Chao Shi Lin Li Guoju Yang Junyan Li Jun Xu Qinfen Gu Xingxing Wang Ji Han Tianjun Zhang Yi Li jihong yu State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin University School of Textile and Clothing Yancheng Institute of Technology State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics National Center for Magnetic Resonance in Wuhan Wuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of Sciences Australian Synchrotron International Center of Future Science Jilin University

Silicoaluminophosphate(SAPO) zeolites are well-known catalytic materials because of the mild acidity originating from the isolated SiO4tetrahedra in their frameworks. Regulating the distribution of isolated SiO4tetrahedra in SAPO zeolites is formidably challenging because SiO4tetrahedra tend to agglomerate to form Si islands and the isolated SiO4tetrahedra are difficult to determine using conventional characterization techniques. Here we synthesized Si-island-free SAPO-35 zeolites by using N-methylpiperidine as a new template, which exhibited excellent thermal stability compared to conventional SAPO-35 zeolites and a substantially improved methanol-to-olefins catalytic lifetime even comparable to that of commercial SAPO-34 zeolites. More strikingly, with the aid of high-throughput computations on 44 697 structure models combined with various state-of-the-art characterization techniques, for the first time, we reveal that the host–guest interactions between template molecules and SAPO frameworks determine the specific distributions of isolated SiO4tetrahedra, which are responsible for the improvement in the chemical properties of zeolites. Our work provides an insight into the template-based regulation of isolated SiO4tetrahedra in SAPO zeolites, which opens a new avenue in the discovery of promising zeolite catalysts with optimal Si O4distribution.

关键词： acidity computational chemistry heterogeneous catalysis structure–activity relationships zeolites