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From geometric to charge-distribution symmetry:deeper insights into lifting the performance of dysprosium single-ion magnets

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Science China chemistry 2023年第7期66卷 1989-1996页

作者： Wei Deng Ying-Qian Zhou Shan-Nan Du Ze-Yu Ruan Si-Guo Wu Jun-Liang Liu Ming-Liang Tong key laboratory of bioinorganic and synthetic chemistry of Ministry of Education School of ChemistrySun Yat-Sen UniversityGuangzhou 510006China

Crystal-field symmetry of lanthanide ions plays a critical role in suppressing quantum tunneling of magnetization(QTM)in single-molecule magnets(SMMs),but high-performance SMM design and modulation remain challenging only in view of the geometric symmetry of the first coordination ***,two bis(semicarbazone)/bis(thiosemicarbazone)dysprosium singleion magnets with pentagonal bipyramid geometry were reported,and bis(thiosemicarbazone)lanthanide complexes have never been reported to the best of our *** served as good archetypes to study the magneto-structural relationships based on the charge *** complex with more ideal geometric symmetry displays fast zero-field QTM with negligible“effective barrier”,owing to the defective charge *** modulating the transverse crystal field via the replacement of the O sites with the less charged and larger radius S atoms,it results in lower geometric but higher charge-distribution symmetry,giving rise to the significant suppression of QTM and the enhancement of reversal barrier up to ca.1,000 *** results demonstrate that the charge-distribution symmetry can be chemically tailored by modification of the crystal field,which is essential for designing high-performance SMMs.

关键词： single-molecule magnets crystal field symmetry strategy electrostatic potential analysis bis(thiosemicarbazone)

A Crystalline Supramolecular Rotor Functioned by Dual Ultrasmall Polar Rotators

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Chinese Journal of chemistry 2022年第16期40卷 1917-1923页

作者： Wang Li De-Xuan Liu Wei-Yu Hu Qing-Yan Liu Zi-Yi Du Chun-Ting He Wei-Xiong Zhang Xiao-Ming Chen College of chemistry and Chemical Engineering MOE Key Laboratory of Fluorine and Silicon for Energy Materials and ChemistryJiangxi Normal UniversityNanchangJiangxi330022 China School of chemistry MOE Key Laboratory of Bioinorganic and Synthetic ChemistrySun Yat-Sen UniversityGuangzhouGuangdong510275 China

As an extended model of conventional molecular rotors,a conceived construction of novel crystalline molecular rotor that simultaneously contains two discrete polar rotators is presented *** supramolecular self-assembly of 18-crown-6 host and two rotator-containing ion-pair guests affords a three-in-one cocrystal,(2-NH_(3)-iBuOH)(18-crown-6)[ZnBr_(3)(H_(2)O)],in which the hydroxyl group and aqua ligand both function as ultrasmall polar *** the basis of the variable-temperature single-crystal X-ray diffraction,variable-temperature/frequency dielectric response,density functional theory calculations,and molecular dynamics simulations,it is found that such dual polar rotators experience a gradually enhanced rotation with increasing temperature,and more importantly,could be controlled by a reversible polar-to-polar structural phase transition,i.e.,from a“single-(polar rotator)”state at low-temperature phase to a“mixed-dual-(polar rotator)”state in the vicinity of transition,and to an unusual“synchronized-dual-(polar rotator)”state at high-temperature phase.

关键词： Molecular rotor Host-guest system Dielectric relaxation Molecular dynamics Phase transition

Dual-functional photocatalysis boosted by electrostatic assembly of porphyrinic metal-organic framework heterojunction composites with CdS quantum dots

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中国化学快报:英文版 2023年第9期34卷 165-170页

作者： Zhiyao Chen Sihong Li Qijie Mo Li Zhang Cheng-Yong Su moe laboratory of bioinorganic and synthetic chemistry Lehn Institute of Functional MaterialsSchool of ChemistrySun Yat-sen UniversityGuangzhou 510006China

Photocatalytic dual-functional reaction under visible light irradiation represents a sustainable development *** detail,H2production coupled with benzylamine oxidation can remarkably lower the cost by replacing sacrificial *** this work,Cd S quantum dots(Cd S QDs)were successfully loaded onto the surface of a porphyrinic metal-organic framework(Pd-PCN-222)by the electrostatic selfassembly at room *** consequent Pd-PCN-222/CdS heterojunction composites displayed superb photocatalytic activity under visible light irradiation,achieving a H2production and benzylamine oxidation rate of 5069 and 3717μmol g^(-1)h^(-1)with>99%selectivity in 3 *** is no noticeable loss of catalytic capability during three successive *** studies by in situ electron spin resonance and X-ray photoelectron spectroscopy disclosed that CdS QDs injected photoexcited electrons to Pd-PCN-222 and then Zr6clusters under visible-light irradiation,and thus Cd S QDs and Zr6clusters behave as the photocatalytic oxidation and reduction centers,respectively.

关键词： Metal-organic framework composites Electrostatic self-assembly Dual-functional photocatalysis CdS quantum dots Metalloporphyrin

Single-atomic Fe anchored on hierarchically porous carbon frame for efficient oxygen reduction performance

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Chinese Chemical Letters 2022年第2期33卷 1070-1073页

作者： Yaling Jia Fangshuai Zhang Qinglin Liu Jun Yang Jiahui Xian Yamei Sun Yinle Li Guangqin Li moe laboratory of bioinorganic and synthetic chemistry Lehn Institute of Functional MaterialsSchool of ChemistrySun Yat-sen UniversityGuangzhou 510275China

Exploring platinum group metal-free electrocatalysts with superior catalytic performance and favorable durability for oxygen reduction reaction is a remaining bottleneck in process of developing sustainable techniques in energy storage and conversion. Herein, a hierarchical porous single atomic Fe electrocatalyst(Fe/Z8-E-C) is rationally designed and synthesized via acid etching, calcination, adsorption of Fe precursor and recalcination processes. This unique electrocatalyst Fe/Z8-E-C shows excellent oxygen reduction performance with a half-wave potential of 0.89 V in 0.1 mol/L KOH, 30 m V superior to that of commercial Pt/C(0.86 V), which is also significantly higher than that of typical Fe-doped ZIF-8 derived carbon nanoparticles(Fe/Z8-C) with a half-wave potential of 0.84 V. Furthermore, Fe/Z8-E-C-based Zn-air battery exhibits greatly enhanced peak power density and specific capacity than those of original Fe/Z8-C,verifying the remarkable performance and practicability of this specially designed hierarchical structure due to its efficient utilization of the active sites and rapid mass transfer. This present work proposes a new method to rationally synthesize single atom electrocatalysts loaded on hierarchical porous frame materials for catalysis and energy conversion.

关键词： Single atom Fe High atom utilization Efficient mass transfer Oxygen reduction reaction Zinc-air battery Efficient performance

High-stability spherical lanthanide nanoclusters for magnetic resonance imaging

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National Science Review 2023年第4期10卷 123-132页

作者： Hai-Ling Wang Donglin Liu Jian-Hua Jia Jun-Liang Liu Ze-Yu Ruan Wei Deng Shiping Yang Si-Guo Wu Ming-Liang Tong key laboratory of bioinorganic and synthetic chemistry of Ministry of Education School of Chemistry Sun Yat-sen University College of chemistry and Materials Science Shanghai Normal University

High-nuclear lanthanide clusters have shown great potential for the administration of high-dose mononuclear gadolinium chelates in magnetic resonance imaging(MRI). The development of high-nuclear lanthanide clusters with excellent solubility and high stability in water or solution has been challenging and is very important for expanding the performance of MRI. We used N-methylbenzimidazole-2-methanol(HL) and LnCl3·6H2O to synthesize two spherical lanthanide clusters, Ln32(Ln = Ho, Ho32; and Ln =Gd, Gd32), which are highly stable in solution. The 24 ligands L-are all distributed on the periphery of Ln32and tightly wrap the cluster core, ensuring that the cluster is stable. Notably, Ho32can remain highly stable when bombarded with different ion source energies in HRESI-MS or immersed in an aqueous solution of different pH values for 24 h. The possible formation mechanism of Ho32was proposed to be Ho(Ⅲ),(L)-and H2O → Ho3(L)3/Ho3(L)4→ Ho4(L)4/Ho4(L)5→ Ho6(L)6/Ho6(L)7→ Ho16(L)19→Ho28(L)15→ Ho32(L)24/Ho32(L)21/Ho32(L)23. To the best of our knowledge, this is the first study of the assembly mechanism of spherical high-nuclear lanthanide clusters. Spherical cluster Gd32, a form of highly aggregated Gd(Ⅲ), exhibits a high longitudinal relaxation rate(1 T, r1= 265.87 mM-1·s-1). More notably, compared with the clinically used commercial material Gd-DTPA, Gd32has a clearer and higher-contrast T1-weighted MRI effect in mice bearing 4T1 tumors. This is the first time that high-nuclear lanthanide clusters with high water stability have been utilized for MRI. High-nuclear Gd clusters containing highly aggregated Gd(Ⅲ) at the molecular level have higher imaging contrast than traditional Gd chelates; thus, using large doses of traditional gadolinium contrast agents can be avoided.

关键词： T1-weighted MRI lanthanide clusters high stability low toxicity assembly mechanism

Thermal expansion-quench of nickel metal-organic framework into nanosheets for efficient visible light CO_(2) reduction

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Chinese Chemical Letters 2023年第2期34卷 249-253页

作者： Liuyong Chen Qinglin Liu Jun Yang Yinle Li Guangqin Li moe laboratory of bioinorganic and synthetic chemistry Lehn Institute of Functional MaterialsSchool of ChemistrySun Yat-sen UniversityGuangzhou 510275China

Metal-organic framework nanosheets (MOF NNs) offer potential opportunities for many applications,but an efficient strategy for the scalable preparation of few-layered two-dimensional (2D) MOF NNs are still a major ***,we present an efficient top-down method for the synthesis of the Ni-BDC(Ni_(2)(OH)_(2)(1,4-BDC);1,4-BDC=1,4-benzenedicarboxylate) nanosheets utilizing a novel thermal expansionquench method of the flowerlike bulky MOFs in liquid *** obtained Ni-BDC nanosheets exhibit significantly enhanced photocatalytic performance of reductive CO_(2)deoxygenation (7.0μmol h^(-1)mg^(-1)) under visible light illumination compared with the bulky MOFs,due to much higher surface area for CO_(2)adsorption,more abundant active sites exposed and stronger electron transport ability of the *** importantly,this synthetic strategy can be extended to fabricate other MOF nanosheets which also exhibit significantly improved performance for deoxygenative CO_(2)reduction compared to their bulky *** work may provide a guideline for preparing other 2D layered photocatalysts materials to realize energy conversion applications.

关键词： Thermal expansion-quench Metal-organic framework(MOF) Two-dimensional Ni-BDC nanosheets Visible light CO_(2)photoreduction

Ultrathin two-dimensional porphyrinic metal-organic framework nanosheets induced by the axial aryl substituent

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Chinese Chemical Letters 2023年第7期34卷 117-121页

作者： Jurong Dong Yufei Wang Yu-Lin Lu Li Zhang moe laboratory of bioinorganic and synthetic chemistry Lehn Institute of Functional MaterialsSchool of ChemistrySun Yat-Sen UniversityGuangzhou 510006China

Ultrathin two-dimensional metal-organic framework nanosheets have emerged as a promising kind of heterogeneous catalysts. Herein, we report a new kind of 2D porphyrinic metal-organic framework nanosheets of Rh2-PCN-222, which was prepared from the self-assembly of the metalloporphyrin ligand Rh(TCPP)(DCB)(TCPP = 5,10,15,20-tetrakis(4-methoxycarbonylphenyl)porphyrin;DCB = 3,4-dichlorobenzene) and ZrCl_(4) in the presence of two kinds of monocarboxylic acids as the modulating reagent. The thickness of Rh2-PCN-222 nanosheets was characterized by atomic force microscopy(AFM)and determined to be 5.4-9.6 nm. It was found that the axial aryl dichlorophenyl substituent, which controlled the anisotropic growth of MOFs, was essential for the formation of nanosheets. Catalytic results showed that Rh2-PCN-222 nanosheets were efficient for CO_(2) transformation.

关键词： Metalloporphyrin Axial aryl substituent 2D MOF nanosheets CO_(2)transformation Heterogeneous catalysis

Catalytic Enantioselective Construction of Chiral Benzo-Fused N-Heterocycles through Friedel-Crafts-Type Electrophilic Chlorination

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CCS chemistry 2022年第5期4卷 1486-1498页

作者： Jie Luo Yuanyuan Zhang Fuming Zhong Xiaodan Zhao Institute of Organic chemistry and moe key laboratory of bioinorganic and synthetic chemistry School of ChemistrySun Yat-sen UniversityGuangzhou 510275

Chiral benzo-fused N-heterocycles are frequently found in natural and synthetic ***,their synthesis usually suffers from different limitations such as difficulty in accessing appropriate starting materials and unsatisfactory *** this work,an unprecedented chiral sulfide-catalyzed enantioselective Friedel-Crafts-type electrophilic chlorination is shown to construct various 3,4-functionalized tetrahydroquinolines with excellent enantio-and diastereoselectivities from readily available aniline ***,employing N-allyl 1-naphthanilides as substrates,divergent reactions via chlorocarbocyclization and dearomatization occurred to afford two chiral polycyclic benzo-fused *** system that we developed extends the scope of asymmetric chlorination to general substrateswithout the need of a N-H group,and significantly promotes the synthesis of enantioenriched benzo-fused N-heterocycles.

关键词： benzo-fused N-heterocycles asymmetric synthesis chiral sulfide catalysis electrophilic chlorination dearomatization divergent reactions

Recent progress on Sn_(3)O_(4)nanomaterials for photocatalytic applications

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 231-244页

作者： Xin Yu Congcong Li Jian Zhang Lili Zhao Jinbo Pang Longhua Ding Institute for Advanced Interdisciplinary Research(iAIR) School of Chemistry and Chemical EngineeringUniversity of JinanJinan 250022China School of Sino-German Engineering Shanghai Technical Institute of Electronics and InformationShanghai 201411China Division of Systems and synthetic Biology Department of Life SciencesChalmers University of Technology41296 GöteborgSweden

Tin(IV)oxide(Sn_(3)O_(4))is layered tin and exhibits mixed valence *** has emerged as a highly promising visible-light pho-tocatalyst,attracting considerable *** comprehensive review is aimed at providing a detailed overview of the latest advance-ments in research,applications,advantages,and challenges associated with Sn_(3)O_(4)photocatalytic *** fundamental con-cepts and principles of Sn_(3)O_(4)are ***_(3)O_(4)possesses a unique crystal structure and optoelectronic properties that allow it to ab-sorb visible light efficiently and generate photoexcited charge carriers that drive photocatalytic ***,strategies for the control and improved performance of Sn_(3)O_(4)photocatalytic nanomaterials are *** control,ion doping,and hetero-structure construction are widely employed in the optimization of the photocatalytic performance of Sn_(3)O_(4)*** effective imple-mentation of these strategies improves the photocatalytic activity and stability of Sn_(3)O_(4)***,the review explores the diverse applications of Sn_(3)O_(4)photocatalytic nanomaterials in various fields,such as photocatalytic degradation,photocatalytic hydro-gen production,photocatalytic reduction of carbon dioxide,solar cells,photocatalytic sterilization,and optoelectronic *** discus-sion focuses on the potential of Sn_(3)O_(4)-based nanomaterials in these applications,highlighting their unique attributes and ***,the review provides an outlook on the future development directions in the field and offers guidance for the exploration and de-velopment of novel and efficient Sn_(3)O_(4)-based *** the identification of emerging research areas and potential avenues for improvement,this review aims to stimulate further advancements in Sn_(3)O_(4)-based photocatalysis and facilitate the translation of this promising technology into practical applications.

关键词： photocatalysis Sn_(3)O_(4)nanomaterials building heterostructures antibacterial therapy water splitting