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π-conjugated chromophore functionalized high-nuclearity titanium-oxo clusters containing structural unit of anatase for photocatalytic selective oxidation of sulfides

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Rare Metals 2024年第4期43卷 1736-1746页

作者： Ling-Rong Liao Dong-Chun Zheng Pin-Xi Ou Qi-Xin Zhao Wei-Min Xuan Qi Zheng State Key Laboratory for Modification of chemical Fibers and Polymer materials & college of materials Science and engineering Donghua University State Key Laboratory for Modification of chemical Fibers and Polymer materials and college of chemistry and chemical engineering Donghua University

N-doping has significant influence in manipulating the properties of TiO2,and this has stimulated the development of N-donor-functionalized titanium-oxo clusters（TOCs） as molecular models to study the structure-property relationship.However,the structural type and photoresponsive application are still limited for such TOCs,especially regarding the high-nuclearity TOCs that contain structure unit of TiO2for photocatalysis.Herein,we showed the synthesis of a series of high-nuclearity TOCs 1-3 compounds using π-conjugated 1,10-phenanthroline（phen） as chromophore and N-donor functional ligand.Compound 1 features cocrystal structure composed of one [Ti26]2+and half [Ti22]2+,which renders it as the first cocrystallized TOC containing two positively charged species and phen-functionalized TOC showing the highest nuclearity up to 37 Ti centers.By adjusting the synthetic conditions,the individual {Ti22} and {Ti26} clusters can also be isolated as Compounds 2 and 3,respectively.The core structure of {Ti22} is mainly constructed from four lacunary {Ti4} derived from pentagonal {Ti（Ti）5} unit,while {Ti26} is built from four complete {Ti（Ti）5} unit.Notably,a {Ti8O14} structure unit of anatase TiO2can be identified in {Ti26}.Based on the unique structural features and proper photophysical and photochemical properties of Compounds 1-3,they are applied for photocatalytic sulfoxidation.Owing to the presence of anatase structure unit in {Ti26} and the synergistic effect from {Ti22} and {Ti26},the catalytic performance presents in the order of Compound 1> Compound 3> Compound 2.This work provides excellent models to understand the structureproperty relationship from the perspective of cocrystallization and Ti-O binding model and will further promote the application of TOCs as functional catalysts for organic transformation.

关键词： Titanium-oxo cluster Molecular model of anatase TiO 2 High nuclearity π-conjugated chromophore Photocatalytic sulfoxidation

Efficient and stable PtFe alloy catalyst for electrocatalytic methanol oxidation with high resistance to CO

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Journal of Energy chemistry 2024年第3期90卷 327-336,I0008页

作者： Qian Yang Sifan Zhang Fengshun Wu Lihua Zhu Guang Li Mingzhi Chen An Pei Yingliang Feng Jiangxi Provincial Key Laboratory of Functional Molecular materials chemistry College of Chemistry and Chemical EngineeringFaculty of Materials Metallurgy and ChemistryJiangxi University of Science and TechnologyGanzhou 341000JiangxiChina college of chemistry and chemical engineering Xiamen UniversityXiamen 361005FujianChina

Direct methanol fuel cells(DMFC) are widely considered to be an ideal green energy conversion device but their widespread applications are limited by the high price of the Pt-based catalysts and the instability in terms of surface CO toxicity in long-term operation.Herein,the PtFe alloy nanoparticles(NPs) with small particle size(~4.12 nm) supported on carbon black catalysts with different Pt/Fe atomic ratios(Pt_(1)Fe_(2)/C,Pt_(3)Fe_(4)/C,Pt_(1)Fe_(1)/C,and Pt_(2)Fe_(1)/C) are successfully prepared for enhanced anti-CO poisoning during methanol oxidation reaction(MOR).The optimal atomic ratio of Pt/Fe for the MOR is 1:2,and the mass activity of Pt_(1)Fe_(2)/C(5.40 A mg_(Pt)^(-1)) is 13.5 times higher than that of conventional commercial Pt/C(Pt/C-JM)(0.40 A mg_(Pt)^(-1)).The introduction of Fe into the Pt lattice forms the PtFe alloy phase,and the electron density of Pt is reduced after forming the PtFe alloy.In-situ Fourier transform infrared results indicate that the addition of oxyphilic metal Fe has reduced the adsorption of reactant molecules on Pt during the MOR.The doping of Fe atoms helps to desorb toxic intermediates and regenerate Pt active sites,promoting the cleavage of C-O bonds with good selectivity of CO_(2)(58.1%).Moreover,the Pt_(1)Fe_(2)/C catalyst exhibits higher CO tolerance,methanol electrooxidation activity,and long-term stability than other Pt_(x)Fe_(y)/C catalysts.

关键词： Alloy catalyst PtFe Methanol oxidation In-situ FTIR CO resistance

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Rational design of metal selenides nanomaterials for alkali metal ion（Li+/Na+/K+） batteries: current status and perspectives

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Rare Metals 2024年第5期43卷 1906-1931页

作者： Rui Sun Feng Xu Cai-Hong Wang Sheng-Jun Lu Yu-Fei Zhang Hao-Sen Fan college of materials Science and Metallurgy engineering Guizhou University School of chemistry and chemical engineering Guangzhou University

Recently,metal selenides have obtained widespread attention as electrode materials for alkali （Li+/Na+/K+） batteries due to their promising theoretical capacity and mechanism.Nevertheless,metal selenides,similar to metal oxides and sulfides,also suffer from severe volume explosion during repeated charge/discharge processes,which results in the structure collapse and the following pulverization of electrode materials.Hence,it leads to poor cycle stability and influencing their further application.In order to solve these issues,some special strategies,including elemental doping,coupling with carbon materials,synthesis of the bimetal selenides with heterostructure,etc.,have been gradually applied to design novel electrode materials with outstanding electrochemical performance.Herein,the recent research progress on metal selenides as anodes for alkali ion batteries is summarized,including the regulation of crystal structure,synthesis strategies,modification methods,and electrochemical mechanisms and kinetics.Besides,the challenges of metal selenides and the perspective for future electrode material design are proposed.It is hoped to pave a way for the development of metal selenide electrode materials for the potential applications for alkali metal ion （Li+/Na+/K+） batteries.

关键词： Rational design Metal selenides Nanostructure Li + batteries Na + batteries K + batteries

Fine structure and facet analyses of tunnel-structured FeOOH nanocrystals

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Progress in Natural Science:materials International 2024年第1期34卷 172-177页

作者： Xuemei Zeng Yanshuai Li Wenjun Song Yun Li Dewu Yin Yifei Yuan Kun He college of chemistry and materials engineering Wenzhou University

The development of energy storage systems in the future relies on identifying suitable target materials and synthesizing target materials with controllable physicochemical properties to unlock their electrochemical contributions. Based on the structure-property-performance relationship established in materials science, it is crucial to determine the fine structure of key functional materials. Among these materials, tunnel-structured β-FeOOH is widely studied due to its low-cost, decent performance and environmental friendliness; yet, its fine structure in terms of the atomic framework and surface configuration has not been well understood. In this work, we successfully synthesized β-FeOOH nanorods and analyzed their crystallographic features via transmission electron microscopy(TEM). By combining ultramicrotome and aberration-corrected scanning TEM with atomic resolution,we first experimentally revealed the structural details of β-FeOOH featuring 1 × 1 tunnels and 2 × 2 tunnels along the c-axis([001]), the same as the nanorod growth direction. The dominant exposed facets of β-FeOOH nanorods were further revealed to be {010}. Such fine structural elucidation unveils the long-existing mystery in this material system, which is expected to contribute to structural/compositional engineering toward functionality optimization in the near future.

关键词： β-FeOOH tunnel Anisotropic growth Atomic resolution Nanorod Energy storage

NIR-IIb-triggered photodynamic therapy combined with chemotherapy platform based on rare-earth-doped nanoparticles

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Rare Metals 2024年第7期43卷 3220-3231页

作者： Zhuo Tu Yong Wan Juan Ge Chen-Chen Li Tao Liang Zhen Li college of Health Science and engineering College of Chemistry and Chemical EngineeringHubei University

Photodynamic therapy（PDT）,with high spatiotemporal selectivity,minimal side effects and less drug resistance,has emerged as a promising approach for the treatment of cancer.However,inadequate penetration depth and poor efficacy seriously restrict its practical application.To address these challenges,we developed a combined therapy platform（RENP@C/D-FA） based on rare-earth-doped nanoparticles（RENPs） with a structure of NaErF4:Tm（0.5%）@NaYF4,on which photosensitizer Ce6（chlorin e6） and chemo-therapeutic drug（DOX）(doxorubicin) were loaded by encapsulating with an amphiphilic polymer distearoyl phosphatidylethanolamine-polyethylene glycol-folic acid（DSPE-PEG-FA）.RENPs with NaErF4as the matrix possess multiple excitation/emission peaks,enabling activation of PDT under near-infrared-Ⅱb（NIR-Ⅱb,1500-1700 nm） excitation and luminescence imaging in NIR-Ⅱb region by absorbing 808 nm near-infrared photons.Furthermore,DOX can be selectively released in the acidic microenvironment of tumors.Benefiting from the tumor targeting capability of folic acid,this platform can successfully ablate tumor cells and inhibit tumor growth by combining PDT and chemotherapy.This innovative approach holds great promise as a powerful tool for cancer treatment,showing the potential to revolutionize PDT.

关键词： Photodynamic therapy Rare-earth-doped nanoparticles NIR-IIb Chemotherapy Combined therapy

Molecular solid solution of lanthanide-titanium-oxo clusters with enhanced photocatalytic hydrogen evolution

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Science China chemistry 2024年第2期67卷 529-535页

作者： Rong Chen Chao-Long Chen Hui Zhang Zi-Han Wang Fu-Li Sun Ming-Hao Du Gui-Lin Zhuang Cheng Wang La-Sheng Long Lan-Sun Zheng Xiang-Jian Kong Collaborative Innovation Centre of chemistry for Energy materials State Key Laboratory of Physical chemistry of Solid Surfaces and Department of chemistry College of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China college of chemical engineering Zhejiang University of TechnologyHangzhou310032China

Molecular solid solutions of metal clusters containing different metal centers with well-defined structures can accurately regulate the HOMO-LUMO gap,but are rarely available.Herein,a series of colorless lanthanide-titanium-oxo clusters Ln_(2)Ti_4(μ_(2)-O)_(2)(μ_(3)-O)_4(Piv)_(10)(THF)_(2)(Ln_(2)Ti_4,Ln = Eu,Gd,Tb,and Ce,HPiv = pivalic acid) were synthesized by the reaction of pivalic acid with Ln(Ac)_(3) and titanium isopropoxide.The light yellow crystal of cluster solid solutions Eu_(2)Ti_(4-x)Cd_(x),containing a mixture of Eu_(2)Ti_4 and Eu_(2)Ti_(3)Cd,was obtained by in situ doping Cd^(2+) and S^(2–).Eu_(2)Ti_(3.92)Cd_(0.08) displays efficient photocatalytic hydrogen evolution activity without a co-catalyst,which is up to 2.6 times that of Eu_(2)Ti_4.Femtosecond time-resolved transient absorption spectroscopy and spin-polarized density functional calculations showed that the enhanced photocatalytic performance of Eu_(2)Ti_(4-x)Cd_(x) can be attributed to the narrower HOMO-LUMO gap and lower LUMO position than that of Eu_(2)Ti_4.This studyprovides an in situ doping method to realize the simple preparation of cluster solid solution.

关键词： molecular solid solution lanthanide-titanium-oxo clusters photocatalytic hydrogen evolution

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Highly sensitive fluorescent sensing and photocatalytic degradation performance of two-dimensional Tb-organic network

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Journal of Rare Earths 2024年第2期42卷 303-313,I0003页

作者： Ting Gao Zhihu Ma Yixia Ren Zhixiang Wang Meili Zhang Xiaoli Chen Jijiang Wang Laboratory of New Energy and New Function materials Shaanxi Key Laboratory of Chemical Reaction EngineeringCollege of Chemistry and Chemical EngineeringYan'an UniversityYan'an716000China

A novel tetra-nuclear Tb-organic network,named as [Tb_(4)(2-pyia)_(6)(HAc)_(0.5)(2,2'-bipy)(H_(2)O)_(4.5)]·2,2'-bipy·H_(2)O(1),was synthesized hydrothermally based on 5-(pyridin-2-ylmethoxy) isophthalic acid(H_(2)pyia) and 2,2'-bipyridine(2,2'-bipy) ligands,and characterized by single crystal X-ray diffraction,thermogravimetric(TG) analyses,powder X-ray diffraction(PXRD) and infrared(IR) technology.1 possesses a two-dimensional network based on the tetra-nuclear inorganic building units,and the π-πstacking interactions between the pyia^(2-) ligands and the guest 2,2'-bipy molecules play an important role in the forming of 3D supramolecular structure.1 exhibits excellent fluorescent sensing performance for Fe^(3+)(1.26×10^(-8) mol/L),Cr_(2)O_(7)^(2-)(8.1×10^(-7) mol/L),2,4,6-trinitrophenol(TNP)(2.71×10^(-8) mol/L)and tetracycline(TCT)(2.76×10^(-7) mol/L) in aqueous solution with lower detection concentrations.The sensing mechanisms of 1 were investigated by density functional theory(DFT) calculations,ultraviolet-visible(UV-Vis) diffuse reflectance spectroscopy,PXRD and fluorescent lifetime analyses.The activated product of 1 was prepared by heating at 255℃ under constant pressure and used to photo-catalytically degrade TCT.Both 1 and the activated one have good photocatalytic degradation performance for TCT with degradation rates of 84.29% and 96.07%,respectively.The photocatalytic mechanisms were discovered by UV-Vis diffuse reflectance spectroscopy and radical trap experiments.The Tb-organic framework might be an excellent multifunctional fluorescent sensor and a good photocatalytic agent for TCT degradation in the future.

关键词： Tb-organic network Fluorescent sensing Photocatalytic degradation Rare earths

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Transition metal clusters with precise numbers of atoms anchored on graphdiyne as multifunctional electrocatalysts for OER/ORR/HER:a computational study

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Rare Metals 2024年第7期43卷 3107-3117页

作者： Xin-Yang Liu Jing-Wei Liu Gang Li Jing-Xiang Zhao college of chemistry and chemical engineering Harbin Normal University

Subnanometer metal clusters play an increasingly important role in heterogeneous catalysis due to their high catalytic activity and selectivity.In this work,by means of the density functional theory（DFT） calculations,the catalytic activities of transition metal clusters with precise numbers of atoms supported on graphdiyne(TM1-4@GDY,TM=V,Cr,Mn,Fe,Co,Ni,Cu,Ru,Rh,Pd,Ir,Pt) were investigated for oxygen evolution reactions（OER）,oxygen reduction reactions（ORR） and hydrogen evolution reactions（HER）.The computed results reveal that the Pd2,Pd4and Pt1anchored graphdiyne can serve as trifunctional catalysts for OER/ORR/HER with the overpotentials of 0.49/0.37/0.06,0.45/0.33/0.12 and 0.37/0.43/0.01 V,respectively,while Pd1and Pt2@graphdiyne can exhibit excellent catalytic performance for water splitting（OER/HER） with the overpotentials of 0.55/0.17 and 0.43/0.03 V.In addition,Ni1and Pd3anchored GDY can perform as bifunctional catalysts for metal-air cells（OER/ORR） and fuels cells（ORR/HER） with the overpotentials of 0.34/0.32 and 0.42/0.04 V,respectively.Thus,by precisely controlling the numbers of atoms in clusters,the TM1-4anchored graphdiyne can serve as promising multifunctional electrocatalysts for OER/ORR/HER,which may provide an instructive strategy to design catalysts for the energy conversation and storage devices.

关键词： Density functional theory Graphdiyne Single-cluster catalysts Multifunctional electrocatalysts Overpotential

Intrinsic pentagon defect engineering in multiple spatial-scale carbon frameworks for efficient triiodide reduction

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Journal of Energy chemistry 2024年第8期95卷 20-28页

作者： Siyi Hou Xuedan Song Chang Yu Jiangwei Chang Yiwang Ding Yingbin Liu Xiubo Zhang Weizhe Liu Jieshan Qiu State Key Lab of Fine chemicals Liaoning Key Lab for Energy Materials and Chemical Engineering Frontier Science Center for Smart Materials School of Chemical EngineeringDalian University of Technology Liaoning Key Lab for Energy materials and chemical engineering Frontier Science Center for Smart Materials School of Chemistry Dalian University of Technology State Key Laboratory of chemical Resource engineering College of Chemical Engineering Beijing University of Chemical Technology

Intrinsic topological defect engineering has been proven as a promising strategy to elevate the electrocatalytic activity of carbon materials. However, the controllable construction of high-density and specific topological defects in carbon frameworks to reveal the relationship between reactivity and defect structure remains a challenging task. Herein, the intrinsic pentagon carbon sites that can favor electron overflow and enhance their binding affinity towards the intermediates of catalytic reaction are firstly presented by the work function and the p-band center calculations. To experimentally verify this, the cage-opening reaction of fullerene is proposed and utilized for synthesizing carbon quantum dots with specific pentagon configuration(CQDs-P), subsequently utilizing CQDs-P to modulate the micro-scale defect density of three-dimensional reduced graphene oxide(rGO) via π-π interactions. The multiple spatial-scale rGO-conjugated CQDs-P structure simultaneously possesses abundant pentagon and edge defects as catalytic active sites and long-range-ordered π electron delocalization system as conductive network. The defects-rich CQDs-P/rGO-4 all-carbon-based catalyst exhibits superb catalytic activity for triiodide reduction reaction with a high photoelectric conversion efficiency of 8.40%, superior to the Pt reference(7.97%). Theoretical calculations suggest that pentagon defects in the carbon frameworks can promote charge transfer and modulate the adsorption/dissociation behavior of the reaction intermediates, thus enhancing the electrocatalytic activity of the catalyst. This work confirms the role of intrinsic pentagon defects in catalytic reactions and provides a new insight into the synthesis of defects-rich carbon catalysts.

关键词： Carbon quantum dots Defect engineering Electrocatalytic activity Pentagon carbon Triiodide reduction