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Nano Research 2024年第5期17卷 4006-4015页

作者： xiaowei He Tianshuai Wang Lidong Tian Qiuyu Zhang School of Chemistry and Chemical Engineering Xi’an Key Laboratory of Functional Organic Porous MaterialsKey Laboratory of Special Functional and Smart Polymer Materials of Ministry of Industry and Information TechnologyNorthwestern Polytechnical UniversityXi’an 710072China Chongqing Science and Technology Innovation Center of Northwestern Polytechnical University Chongqing 401135China College of materials Science and Engineering Xi’an University Science and TechnologyXi’an 710054China

Heterostructure engineering by coupling different nanocrystals has received extensive attention because it can enhance the reaction kinetics of the anode of sodium-ion batteries(SIBs).However,constructing high-quality heterostructure anode materials through green and environmentally friendly methods remains a ***,we have proposed a simple one-step method by recycling the electronic waste metal materials to synthesize the Cu_(1.94)S/ZnS heterostructure *** with the experimental analysis and first principle calculations,we find that the synergistic effect of different components in heterostructure structures can significantly enhance the reversible capacity and rate performance of anode *** on the constructed Cu_(1.94)S/ZnS anode,we obtain a superior reversible capacity of 440 mAh·g^(-1) at 100 mA·g^(-1) and 335 mAh·g^(-1) after 3000 cycles at 2000 mA·g^(-1).Our work sheds new light on designing high-rate and capacity anodes for SIBs through the greenness synthesis method.

关键词： sodium-ion batteries heterostructure reversible capacity environmentally synthesis process

Photocaged prodrug under NIR light-triggering with dual-channel fluorescence: in vivo real-time tracking for precise drug delivery

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Science China Chemistry 2018年第10期61卷 1293-1300页

作者： Zhiqian Guo Yaguang Ma Yajing Liu Chenxu Yan Ping Shi He Tian Wei-Hong Zhu key laboratory for Advanced materials and Institute of Fine chemicals Shanghai Key Laboratory of Functional Materials Chemistry School of Chemistry and Molecular Engineering East China University of Science and Technology State key laboratory of Bioreactor Engineering East China University of Science and Technology

Light-triggered drug delivery system is an effective strategy for precise diagnosis and therapy in cancer treatment. However, it suffers from difficultly balancing the dosimetry of drug with light dose and a lack of in vivo models for validating their clinical benefits. Here we report an unprecedented near-infrared(NIR) light photocaged cyanine-based prodrug Cy-CPT-Biotin with dual-channel fluorescence mode, enabling NIR light to precisely regulate where, when and how the intact and active prodrugs are delivered. The synergy of photochemical reaction and modulation in π-conjugated polyene backbone of cyanine can fully perform distinct dual-channel fluorescence changes in a NIR light-mediated manner. The prodrug has striking characteristics of excellent tumor-targeting ability, real-time monitoring of the in vivo behaviors by dual-channel mode and NIR-light triggering,especially for achieving fine regulation and on-demand drug release in the precise dosimetry of drug with light dose in living animals. This optical orthogonality strategy that conjuncts with NIR light-triggered and dual-channel fluorescence in vivo imaging provides a powerful tool for in vivo real-time tracking and finely tuning the prodrug release for precise drug delivery.

关键词： near-infrared cyaninc dye dual-channel fluorescence drug-release photocage tumor targeting

Dynamically observing the formation of MOFs-driven Co/N-doped carbon nanocomposites by in-situ transmission electron microscope and their application as high-efficient microwave absorbent

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Nano Research 2022年第8期15卷 6819-6830页

作者： You Zhou xia Deng Hongna xing Hongyang Zhao Yibo Liu Lisong Guo Juan Feng Wei Feng Yan Zong xiuhong Zhu xinghua Li Yong Peng xinliang Zheng School of Physics State Key Laboratory of Photoelectric Technology and Functional MaterialsNorthwest UniversityXi’an 710127China School of materials and Energy Electron Microscopy Centre of Lanzhou UniversityLanzhou UniversityLanzhou 730000China School of Chemistry Xi’an Key Laboratory of Sustainable Energy Materials ChemistryXi’an Jiaotong UniversityXi’an 710049China

Metal-organic frameworks(MOFs)derived magnetic carbon-based nanocomposites have drawn widespread attentions due to the well distributed nanocrystals in carbon *** observing the formation process is urgently ***,taking zeolitic imidazolate framework(ZIF)-67 as an example,the pyrolysis process is investigated by in-situ transmission electron microscopy(TEM)assisted with ex-situ *** nanocrystals are evenly distributed in carbon at the initial stage of *** increasing pyrolysis temperature,the nanocrystals grow bigger and migrate to carbon *** carbon texture transfers from amorphous to crystalline at 600°C,and thoroughly converts at 800°***-situ heating TEM shows that more tiny Co nanocrystals move out from the carbon texture by increasing temperature from 700 to 800°*** 1,000°C,some escaped tiny Co nanocrystals are volatilized and *** residual escaped Co nanocrystals catalyze the formation of carbon nanotubes(CNTs).Due to the synergistic effect between Co and carbon as well as porous structure,the nanocomposites show high-efficient microwave absorption performance,which can be tuned by pyrolysis temperature,heating rate,and mass *** the mass fraction is 30 wt.%,the nanocomposites obtained at 600 or 700°C display remarkable microwave absorption with optimal reflection loss(RL)smaller than−70 dB and effective absorption band larger than 4.9 *** the in-situ and ex-situ techniques,some key findings were observed:(1)graphitization of carbon;(2)volatilization of Co nanocrystals;(3)formation process of CNTs by Co *** findings are helpful to understand the formation of MOFs derived carbon-based composites and expand their practical applications,especially for microwave absorption.

关键词： metal-organic frameworks Co/N-doped carbon nanocomposites in-situ transmission electron microscopy(TEM) microwave absorption

Novel luminescent europium-centered hybrid material covalently grafted with organically modified titania via 2-substituted imidazophenanthroline for fluorescence sensing

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Journal of Rare Earths 2021年第6期39卷 666-673,I0002页

作者： Fenghan Wei Chao Bai Huai-Ming Hu Shi He xiaofang Wang Ganglin Xue key laboratory of Synthetic and Natural functional Molecule of the Ministry of Education College of Chemistry and Materials ScienceNorthwestUniversityXi'an 710127China

By employing a rational approach,we prepared a novel kind of luminescent europium-centered hybrid material named Eu(tta)_(3)NCP-TiO_(2).The resulting material was characterized by FT-IR spectra,SEM,X-ray diffraction,thermogravimetric analysis,and photoluminescence *** hybrid material features the combined advantages of the europium complex and the titania host,exhibiting not only good thermostability,but also long luminescence *** to the excellent luminescence of this material,the application in detecting organic small molecule solvents and metal ions was explored ***,Eu(tta)_(3)NCP-TiO_(2) exhibits superior detection for nitrobenzene molecule and Cu^(2+) ion in DMF(N,N-dimethylformamide) ***,the limit of detection(LOD) of Eu(tta)_(3)NCP-TiO_(2) for nitrobenzene and Cu^(2+) ion can be counted as 5.593× 10^(-5) and 9.566 ×10^(-5) mol/L,*** results demonstrate that Eu(tta)_(3)NCP-TiO_(2) can serve as an efficient fluorescence probe for the detection of sensing of nitrobenzene and Cu^(2+) ion.

关键词： Hybrid material Ternary europium complex Imidazophenanthroline Titania Fluorescence sensing Rare earths

Gradient-structure-enhanced dielectric energy storage performance of flexible nanocomposites containing controlled preparation of defective TiO_(2) and ferroelectric KNbO_(3) nanosheets

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Nano Research 2024年第5期17卷 4079-4088页

作者： Yan Wang Lili Zhao Ruicong Chen Wenhui Zhao Dengwei Hu Haoran Wang Bin Cui key laboratory of Synthetic and Natural functional Molecule of the Ministry of Education Shaanxi key laboratory of Physico–Inorganic Chemistry Xi’an Key Laboratory of Functional Supramolecular Structure and MaterialsCollege of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127China School of Information Science and Technology Northwest UniversityXi’an 710127China Engineering Research Center for Titanium Based functional materials and Devices in Universities of Shaanxi Province Faculty of Chemistry and Chemical EngineeringBaoji University of Arts and SciencesBaoji 721013China

Next generation power system needs dielectrics with increased dielectric energy ***,the low energy density of dielectrics limits their ***,an asymmetric trilayered nanocomposite,with a transition layer(TL),an insulation layer(IL),and a polarization layer(PL),is designed based on poly(vinylidene fluoride)-polymethyl methacrylate(PVDF-PMMA)matrix using KNbO_(3)(KN)and TiO_(2)(TO)as the *** morphology and defect control of the two-dimensional nano KN and nano TO fillers are realized via a hydrothermal method to increase the composite breakdown strength(E_(b))and the composite energy density(U_(e)).The asymmetric trilayered structure leads to a gradient electric field distribution,and the KN and TO nanosheets block charges transfer along z *** a result,the development path of the electrical trees is greatly curved,and E_(b) is effectively *** the Ue value of the nanocomposites reaches 17.79 J·cm^(-3) at 523 MV·m^(-1).On the basis,the composite Ue is further improved by defect control in TO *** nanocomposite KN/TO/PVDF-PMMA containing TO with less oxygen vacancy concentration(calcined at oxygen atmosphere)acquires a high Ue of 21.61 J·cm^(-3) at 548 MV·m^(-1).This study provides an idea for improving the energy storage performance by combining the design of the composite dielectric structure and the control of nanofillers’defect and morphology.

关键词： asymmetric trilayered structure two-dimensional energy density oxygen vacancies breakdown strength dielectric

Inhibiting the bipolar effect via band gap engineering to improve the thermoelectric performance in n-type Bi_(2-x)Sb_(x)Te_(3)for solid-state refrigeration

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Journal of materials Science & Technology 2023年第7期138卷 50-58页

作者： Dongliang Su Jiahui Cheng Shan Li Shengnan Zhang Tu Lyu Chaohua Zhang Junqin Li Fusheng Liu Lipeng Hu College of materials Science and Engineering Shenzhen Key Laboratory of Special Functional MaterialsGuangdong Research Center for Interfacial Engineering of Functional MaterialsGuangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and UtilizationInstitute of Deep Earth Sciences and Green EnergyShenzhen UniversityShenzhen 518060China Superconducting materials Research Center Northwest Institute for Nonferrous Metal ResearchXi’an 710016China

To date,the benchmark Bi_(2)Te_(3)-based alloys are still the only commercial material system used for ther-moelectric solid-state ***,the conspicuous performance imbalance between the p-type Bi_(2-x)Sb_(x)Te_(3)and n-type Bi_(2)Te_(3-x)Se_(x) legs has become a major obstacle for the improvement of cooling devices to achieve higher *** our previous study,novel n-type Bi_(2-x)Sb_(x)Te_(3)alloy has been pro-posed via manipulating donor-like effect as an alternative to mainstream n-type Bi_(2)Te_(3-x)Se_(x).However,the narrow bandgap of Bi_(2-x)Sb_(x)Te_(3)provoked severe bipolar effect that constrained the further improvement of zT near room ***,we have implemented band gap engineering in n-type Bi_(1.5)Sb_(0.5)Te_(3)by employing isovalent Se substitution to inhibit the undesired intrinsic excitation and achieve the dis-tinguished room-temperature ***,the preferential occupancy of Se at Te^(2)site appropriately enlarges the band gap,thereby concurrently improving the Seebeck coefficient and depressing the bipolar thermal *** addition,the Se alloying mildly suppresses the compensation mechanism and essentially preserves the already optimized carrier concentration,which maintains the peak zT near room ***,the large strain field and mass fluctuation generated by Se alloying leads to the remark-able reduction of lattice thermal ***,the zT value of Bi_(1.5)Sb_(0.5)Te_(2.8)Se_(0.2)reaches 1.0 at 300 K and peaks 1.1 at 360 K,which surpasses that of most well-known room-temperature n-type thermoelectric *** results pave the way for n-type Bi_(2-x)Sb_(x)Te_(3)alloys to become a new and promising top candidate for large-scale solid-state cooling applications.

关键词： Thermoelectric Bi_(2)Te_(3) Band gap Bipolar effect Point defects

Organocatalytic asymmetric[2+2] cycloaddition of alkynes with quinones

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Science China Chemistry 2023年第8期66卷 2292-2299页

作者： Huai-Ri Sun Lan Yang Yu Li Le Yu Bo-Bo Gou Atif Sharif Qing-Song Jian Jie Chen Ling Zhou key laboratory of Synthetic and Natural functional Molecule of the Ministry of Education College of Chemistry&Materials ScienceNorthwest UniversityXi’an710127China

A chiral phosphoric acid catalyzed enantioselective[2+2] cycloaddition of alkynylindols or alkynylnaphthols with quinones is disclosed.A class of functionalized cyclobutenes with excellent yields,diastereo-and enantioselectivities were prepared under mild reaction conditions(70 examples,up to 99%yield,99%ee,all>50:1 dr).Mechanistic studies revealed that a dearomatization of indole or naphthol occurred to initiate the cycloaddition,followed by an intramolecular Michael addition with in situ generated allene-iminium or vinylidene-quinone methide *** competitive[2+3] cycloaddition was prevented in this catalytic *** interesting central to axial chirality conversion via a rearrangement process was realized during transformation of the product.

关键词： organocatalysis [2+2]cycloaddition asymmetric catalysis alkynes cyclobutenes

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Semicrystalline Unfused Polymer Donors with Backbone Halogenation toward Cost-Effective Organic Solar Cells

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Chinese Journal of Chemistry 2024年第7期42卷 752-759页

作者： Yuxin Kong Shijie Ju Hongmei Qin Min Hun Jee Simeng xia Jiaqi Ren Chao Gao Jianyu Yuan Wenyan Su Han Young Woo Yuxiang Li School of materials Science and Engineering Xi'an University of Science and TechnologyXianShaanxi 710054China Department of Chemistry Korea UniversitySeoul 02841Republic of Korea xi'an key laboratory of Liquid Crystal and Organic Photovoltaic materials State Key Laboratory of Fluorine&Nitrogen ChemicalsXi'an Modern Chemistry Research InstituteXi'anShaanxi 710065China Jiangsu key laboratory for Carbon-Based functional materials&Devices Institute of Functional Nano&Soft Materials(FUNSOM)Soochow University199 Ren'ai RoadSuzhouJiangsu 215123China

Developing novel unfused building blocks with simple synthesis and low cost is essential to advance and enrich cost-effective poly-mer donors;however,it remains a challenge due to the lack of efficient molecular ***,a class of low-cost and fully unfused polymer donors with precisely regulated backbone planarity via halogenation was designed and synthesized,namely PDTBTBz-2H,PDTBTBz-2F,and *** polymer donors possess a four-step synthesis route with over 80%yield from cheap raw chemicals comparable to existing low-cost polymer donors,such as *** from the planar backbone via in-corporating the F…S non-covalent interactions,PDTBTBz-2F exhibits more robust J-type aggregation in solution and a long-ranged molecular stacking in film relative to PDTBTBz-2H and ***,the systematical study of PDTBTBz-based organic so-lar cells(OSCs)reveals the close relationship between optimized molecular self-assembly and charge separation/transport regarding backbone halogenation when paired with the non-fullerene acceptor(Y6-BO-4F).As a result,the photovoltaic devices based on semicrystalline PDTBTBz-2F achieved a promising power conversion efficiency(PCE)of 12.37%.Our work highlighted the influence of backbone halogenation on the molecular self-assembly properties and a potential unfused backbone motif for further developing cost-effective OSCs.

关键词： Low-cost Polymer donors Backbone halogenation Molecular self-assembly Organic solar cells

Bio-Based Waterborne Poly(Vanillin-Butyl Acrylate)/MXene Coatings for Leather with Desired Warmth Retention and Antibacterial Properties

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Engineering 2024年第5期36卷 250-263页

作者： Jianzhong Ma Li Ma Lei Zhang Wenbo Zhang Qianqian Fan Buxing Han College of Bioresources Chemical and materials Engineering Shaanxi University of Science and TechnologyXi’an 710021China xi’an key laboratory of green chemicals and functional materials Xi’an 710021China College of Chemistry and Chemical Engineering Shaanxi University of Science and TechnologyXi’an 710021China Shaanxi Collaborative Innovation Center of Industrial Auxiliary Chemistry and Technology Shaanxi University of Science and TechnologyXi’an 710021China Institute of Chemistry Chinese Academy of SciencesBeijing 100190China

This study presents a solvent-free,facile synthesis of a bio-based green antibacterial agent and aromatic monomer methacrylated vanillin(MV)using *** resulting MV not only imparted antibacterial properties to coatings layered on leather,but could also be employed as a green alternative to petroleum-based carcinogen styrene(St).Herein,MV was copolymerized with butyl acrylate(BA)to obtain waterborne bio-based P(MV-BA)miniemulsion via miniemulsion ***,MXene nanosheets with excellent photothermal conversion performance and antibacterial properties,were introduced into the P(MV-BA)miniemulsion by ultrasonic *** the gradual solidification of P(MV-BA)/MXene nanocomposite miniemulsion on the leather surface,MXene gradually migrated to the surface of leather coatings due to the cavitation effect of ultrasonication and amphiphilicity of MXene,which prompted its full exposure to light and bacteria,exerting the maximum photothermal conversion efficiency and significant antibacterial *** particular,when the dosage of MXene nanosheets was 1.4 wt%,the surface temperature of P(MV-BA)/MXene nanocomposite miniemulsioncoated leather(PML)increased by about 15℃ in an outdoor environment during winter,and the antibacterial rate against Escherichia coli and Staphylococcus aureus was nearly 100%under the simulated sunlight treatment for 30 ***,the introduction of MXene nanosheets increased the air permeability,water vapor permeability,and thermal stability of these *** study provides a new insight into the preparation of novel,green,and waterborne bio-based nanocomposite coatings for leather,with desired warmth retention and antibacterial *** can not only realize zerocarbon heating based on sunlight in winter,reducing the use of fossil fuels and greenhouse gas emissions,but also improve ability to fight off invasion by harmful bacteria,viruses,and other microorganisms.

关键词： MXene nanosheets Vanillin Styrene substitute Leather coating Photothermal conversion Warmth retention Antibacterial properties

Fine-tuning hydroxylamines as single-nitrogen sources for Pd(0)-catalyzed diamination of o-bromo(or chloro)-biaryls

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Science China Chemistry 2022年第4期65卷 686-693页

作者： Pin Ding Lingbo Han Jiaxing Bai Jingjing Liu xinjun Luan key laboratory of Synthetic and Natural functional Molecule of the Ministry of Education College of Chemistry&Materials ScienceNorthwest UniversityXi’an 710127China

Transition metal-catalyzed diamination by hydroxylamines is a common approach for making three-membered aziridines,while its use for building the larger N-heterocycles is still ***,we report an efficient Pd(0)-catalyzed intermolecular[4+1]annulation of o-bromo(or chloro)-biaryls with bifunctional secondary hydroxylamines for the one-step assembly of synthetically useful ***,a linchpin for this domino reaction was the judicious selection of both the amino-sources and Pd(0)-catalysts for enabling the prerequisite oxidative addition of aryl halides to Pd(0)-species in the presence of hydroxylamines with a labile N-O bond.

关键词： hydroxylamines diamination o-halobiaryls carbazoles palladium

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