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A highly reduced Mo_(74) polyoxometalate featuring high proton conductivity accessed by building block strategy

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Science China chemistry 2024年第3期67卷 862-868页

作者： Shi-Yi Liu Xue-Xin Li Wei-Chao Chen Kui-Zhan Shao Xin-Long Wang Chao Qin Zhong-Min Su key laboratory of Polyoxometalate and Reticular Material chemistry of ministry of education Department of ChemistryNortheast Normal UniversityChangchun 130024China State key laboratory of Supramolecular Structure and Materials Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchun 130021China

Highly reduced polyoxometalates(POMs) are predicted to be used as rather high energy density materials;however,it still suffers from the limited cluster species and reduction *** we demonstrate that it is possible to employ the building block strategy to generate a highly reduced polyoxomolybdate(C_(2)H_(8)N)_(14)(NH_(4))_(4)H_(14)[Mo_(48)-ⅤMo_(26)ⅥO_(202)(OH)_(12)(SO_(4))_(6)]·46H_(2)O(Mo_(74)).The fundamental Mo-based{Mo_x}(x=4,5,and 6) building blocks,which are templated by tetra-coordinated anions{MoO_(4)}or{SO_(4)},not only lay foundation for the formation of Mo_(74) featuring an unprecedented reduction ratio of 65%,but also give rise to SBBs-mediated(secondary building blocks) supramolecular dense packing interactions among the isolated Mo_(74) clusters that are favorable for proton ***,high proton conductivity(2.04×10^(-2)S cm^(-1)) had been realized at 50℃ and 90% relative humidity,revealing one of the well-known POMs-based crystalline proton conducting *** result highlights that this building block approach possesses great potential in producing highly reduced POM systems that can achieve controllable reduced ratio and desirable properties.

关键词： polyoxometalate building block molybdenum highly reduced state proton conduction

Abiotic transformation of chlorinated organics at the active surface of iron-bearing minerals in soils and sediments

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Science China Technological Sciences 2024年第10期67卷 2991-3008页

作者： LI XuXin YAN Chen ZENG YuXi LI WenBin PENG TianWei SONG Biao ZHOU ChengYun College of environmental Science and Engineering Hunan University key laboratory of environmental Biology and Pollution Control (Hunan University) Ministry of Education

Chlorinated organic compounds are emerging pollutants of widespread concern because of their toxicity, bioaccumulation,persistence, and lack of adequate regulatory measures. Their abiotic transformation, facilitated by iron-bearing minerals, is critical to their natural dissipation in soils and sediments. However, further exploration is needed to understand their underlying mechanisms and potential engineering applications under different redox conditions. This paper reviews the abiotic transformation behaviors and mechanisms of chlorinated organics at the active surface of iron-bearing minerals under anoxic and oxic conditions and summarizes the strategies for enhancing the abiotic transformation efficiency of chlorinated organics. The abiotic transformation rate under oxic conditions can be a few orders of magnitude higher than that under anoxic conditions. Under anoxic conditions, chlorinated organics undergo reductive dechlorination through reductive elimination, hydrogenolysis, dehydrohalogenation, and nucleophilic substitution. A close relationship between the abiotic transformation of chlorinated organics and the production of hydroxyl radicals by iron-bearing minerals under oxic conditions was discovered. Synthetic active iron-bearing minerals, carbonaceous materials, and biological synergy can facilitate abiotic dechlorination under anoxic conditions. Meanwhile, the regulation of redox conditions, the introduction of ligands, and the utilization of coexisting anions are proposed to enhance oxidative degradation. This study is expected to improve the comprehension of the abiotic degradation of chlorinated organics mediated by iron-bearing minerals and provide the theoretical foundation for developing new approaches aimed at addressing chlorinated organic pollution.

关键词： chlorinated organic compounds iron-bearing minerals dechlorination degradation remediation

Performance enhancement and active sites identification of Cu-Cd bimetallic oxide derived catalysts for electrochemical CO_(2) reduction

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Journal of Energy chemistry 2024年第4期91卷 50-58页

作者： Cai Wang Xin Hu Bairong Chen Houan Ren Xiaoyu Wang Yilin Zhang Xinyu Chen Yuping Liu Qingxin Guan Wei Li State key laboratory of Elemento-Organic chemistry Key Laboratory of Adv.Energy Mater.Chemistry(Ministry of Education)College of ChemistryNankai UniversityTianjin 300071China

The development of earth-abundant electrocatalysts with high performance for electrochemical CO_(2)reduction(ECR)is of great ***-based catalysts have been widely investigated for ECR due to their unique ability to generate various carbonaceous products,but directing selectivity toward one certain product and identifying the real active sites during ECR are still full of ***,after the incorporation of CdO into CuO,the Cu_(0.5)Cd_(0.5)-O catalyst achieves a 10.3-fold enhancement for CO selectivity in comparison with CuO,and a CO faradic efficiency nearly 90%with a current density around20 mA cm^(-2)could maintain at least 60 ***,a wide CO/H_(2)ratio(0.07-10)is reached on Cu_(x)Cd_(1-x)-O catalysts by varying the Cu/Cd ratio,demonstrating the potential of syngas production using such *** results of ex situ XRD,XPS,and in situ Raman reveal that the real active sites of Cu_(0.5)Cd_(0.5)-O catalysts for CO production during ECR reaction are the reconstructed mixed phases of CuCd alloy and CdCO_(3).In situ FTIR and theoretical calculations further implicate the presence of Cd related species promotes the CO desorption and inhibits the H_(2)evolution,thus leading to an enhanced CO generation.

关键词： CO_(2)reduction Cu-Cd bimetallic Real active sites CO production

From charge storage mechanism to performance:A strategy toward boosted lithium/sodium storage through heterostructure optimization

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Journal of Energy chemistry 2024年第1期88卷 112-124,I0003页

作者： Xiaoke Zhang Guangfa Deng Mianying Huang Zhaohui Xu Jianlin Huang Xuan Xu Zhiguang Xu Maochan Li Lei Hu Xiaoming Lin key laboratory of theoretical chemistry of Environment Ministry of EducationSchool of ChemistrySouth China Normal UniversityGuangzhou 510006GuangdongChina Anhui laboratory of Functional Coordinated Complexes for Materials chemistry and Application School of Chemical and Environmental EngineeringAnhui Polytechnic UniversityWuhu 241000AnhuiChina National Engineering Research Center for Carbohydrate Synthesis Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of EducationJiangxi Normal UniversityNanchang 330022JiangxiChina

Solving the problems of low electrical conductivity and poor cycling durability in transition metal oxidesbased anode materials for lithium-ion batteries(LIBs)and sodium-ion batteries(SIBs)has already turned into an urgent *** this paper,we successfully synthesized Co_(2)VO_(4)/Co compounds with Co-VMOF(metal-organic framework)as a sacrificial template and investigated their electrochemical mechanism in order to improve the electrochemical properties of LIBs and *** optimized heaping configuration and the existence of metallic Co catalyzed the formation of radical ions,thereby facilitating higher conductivity,shortening Li+and Na+transport paths,and providing more active ***_(2)VO_(4)/Co constructed with 2-methylimidazole as a ligand showed a discharge capacity of 1605.1 mA h g^(-1)after 300 cycles at 0.1 A g^(-1)in LIB and 677.2 mA h g^(-1)in *** functional theory(DFT)calculation emphasizes the crucial role of Co_(2)VO_(4)/Co in enhancing electrode conductivity,decreasing the migratory energy barrier,and thereby strengthening electrochemical *** heterostructure building technique may pave the way for the development of high-performance LIBs and ***,the problem of the low first-loop coulombic efficiency faced by transition metal oxides is improved.

关键词： Metal-organic framework Heterostructure Lithium-ion batteries Sodium-ion batteries DFT calculation

In situ embedded bismuth nanoparticles among highly porous carbon fibers for efficient carbon dioxide reduction

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Rare Metals 2024年第9期43卷 4312-4320页

作者： Wei-Jian Guo Ao Zhou Wen-Wen Cai Jin-Tao Zhang key laboratory for Colloid and Interface chemistry(ministry of education) School of Chemistry and Chemical EngineeringShandong UniversityJinan 250100China

Electrocatalysis provides an optimal approach for the conversion of carbon dioxide(CO_(2))into high-value chemicals,thereby presenting a promising avenue toward achieve carbon ***,addressing the selectivity and stability challenges of metal catalysts in electrolytic reduction remains a daunting *** this study,the electrospinning method is employed to fabricate porous carbon nanofibers loaded with bismuth nanoparticles with the help of in situ *** porous carbon nanofibers as conductive support would facilitate the dispersion of bismuth active sites while inhibiting their aggregation and promoting the mass transfer,thus enhancing their electrocatalytic activity and ***,nitrogen doping induces electron delocalization in bismuth atoms through metal-support interactions,thus enabling efficient adsorption of intermediates for improving selectivity based on the theoretical ***,Bi@PCNF-500 exhibits the exceptional selectivity and stability across a wide range of potential ***,its faradaic efficiency(FE)of formate reaches 92.7%in H-cell and94.9%in flow cell,respectively,with good electrocatalytic *** in situ characterization and theoretical calculations elucidate the plausible reaction mechanism to obtain basic rules for designing efficient electrocatalyst.

关键词： Porous carbon nanofiber N-doping Electron delocalization Carbon dioxide reduction

Recent advances in post-chiroptical manipulation of supramolecular aggregates assembled with molecular modules

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Science China chemistry 2024年第9期67卷 2842-2863页

作者： Yanling Shen Wanhua Wu Zhipeng Yu Cheng Yang key laboratory of Green chemistry&Technology of ministry of education College of Chemistry InstitutionSichuan UniversityChengdu 610064China

Recently,various supramolecular assembly systems have been identified where the pre-existing chiral supramolecular structure can be manipulated through environmental adjustments,such as temperature,solvent,and *** changes result in diverse microscopic morphologies during the assembly process and induce chiroptical variations,particularly in circular dichroism(CD)and circularly polarized luminescence(CPL)*** chiroptical properties serve as direct indicators of the chiral supramolecular structure and hold promise for applications in sensing,molecular recognition,asymmetric synthesis,and material *** review focuses on research published in the last five years,highlighting instances where assembled structures aggregated by small organic molecular modules demonstrate in-situ chiroptical changes through external condition *** categorizes and discusses different modes of regulation,aiming to offer insights and guidelines for exploring dynamic changes in assembly processes and designing in-situ adjustable structures of assembly modules.

关键词： supramolecular assemblies post-chiroptical manipulation in-situ structural changes

Polyoxometalates-Modulated Hydrophilic-Hydrophobic Composite Interfacial Material for Efficient Solar Water Evaporation and Salt Harvesting in High-Salinity Brine

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Energy & environmental Materials 2024年第3期7卷 219-227页

作者： Sihang Cheng Cuimei Liu Yingqi Li Huaqiao Tan Yonghui Wang Yangguang Li key laboratory of Polyoxometalate and Reticular Material chemistry of ministry of education Faculty of ChemistryNortheast Normal UniversityChangchun 130024China

Solar vapor generation(SVC)represents a promising technique for seawater desalination to alleviate the global water crisis and energy *** of its main bottleneck problems is that the evaporation efficiency and stability are limited by salt crystallization under high-salinity ***,we demonstrate that the 3D porous melamine-foam(MF)wrapped by a type of self-assembling composite materials based on reduced polyoxometalates(*** blue,HPB),oleic acid(OA),and polypyrrole(PPy)(labeled with MF@HPB-PPy_(n)-OA)can serve as efficient and stable SVC material at high *** characterizations of MF@HPB-PPy_(n)-OA indicate that both hydrophilic region of HPBs and hydrophobic region of OA co-exist on the surface of composite materials,optimizing the hydrophilic and hydrophobic interfaces of the SVC materials,and fully exerting its functionality for ultrahigh water-evaporation and anti-salt *** optimal MF@HPB-PPy_(10)-OA operates continuously and stably for over 100 h in 10wt%***,MF@HPB-PPy_(10)-OA accomplishes complete salt-water separation of 10wt%brine with 3.3kgm^(-2)h^(-1)under 1-sun irradiation,yielding salt harvesting efficiency of 96.5%,which belongs to the record high of high-salinity systems reported so far and is close to achieving zero liquid ***,the low cost of MF@HPB-PPy_(10)-OA(2.56$m^(-2))suggests its potential application in the practical SVC technique.

关键词： heteropoly blue(HPB) hydrophilic-hydrophobic interface polyoxometalates(POM) salt-water separation solar vapor generation(SVG)

Constructing oxygen deficiency-rich V_(2)O_(3)@PEDOT cathode for high-performance aqueous zinc-ion batteries

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Rare Metals 2024年第2期43卷 635-646页

作者： Dong-Fei Sun Zi-Juan Wang Tian Tian Xin Yu Dan-Dan Yu Xiao-Zhong Zhou Guo-Fu Ma Zi-Qiang Lei key laboratory of Eco-functional Polymer Materials of the ministry of education Key Laboratory of Eco-environmental Polymer Materials of Gansu ProvinceSchool of College of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou730070China

Aqueous zinc-ion batteries(AZIBs)have attracted widespread attention due to the advantages of high safety and environmental *** V_(2)O_(3) is a promising cathode,the strong electrostatic interaction between Zn^(2+) and V_(2)O_(3) crystal,and the sluggish reaction kinetics still limit their application in ***,the oxygen defects rich V_(2)O_(3) with conducive poly(3,4-ethylenedioxythiophene)(PEDOT)shell(V_(2)O_(3)-Od@PEDOT)was fabricated for AZIBs by combining the sulfur-assisted thermal reduction and in-situ polymerization *** introduced oxygen vacancies of V_(2)O_(3)–Od@PEDOT weaken the electrostatic interaction between Zn^(2+) and the host material,improving the interfacial electron transport,while the PEDOT coating enhances the structural stability and conductivity of V_(2)O_(3),thus accelerating the reaction *** on the advantages,V_(2)O_(3)–Od@PEDOT electrode delivers a reversible capacity of 495 mAh·g^(−1) at 0.1 A·g^(−1),good rate capability(189 mAh·g^(−1)at 8.0 A·g^(−1)),and an impressive cycling stability with 90.1%capacity retention over 1000 cycles at 8.0 A·g^(−1).The strategy may provide a path for exploiting the other materials for high performance AZIBs.

关键词： Oxygen defects V_(2)O_(3) PEDOT Electrochemical self-optimization Aqueous zinc-ion batteries

Dimensional regulation in gigantic molybdenum blue wheels featuring{(W)Mo_(5)}motifs for enhanced proton conductivity

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Nano Research 2024年第9期17卷 8261-8268页

作者： Yu-Lun Wu Jing Du Hai-Ying Zhang Ming-Jun Hou Qiao-Yue Li Wei-Chao Chen Kui-Zhan Shao Bo Zhu Chao Qin Xin-Long Wang Zhong-Min Su key laboratory of Polyoxometalate and Reticular Material chemistry of ministry of education Department of ChemistryNortheast Normal UniversityChangchun 130024China Hebei key laboratory of Organic Functional Molecules National Demonstration Center for Experimental Chemistry EducationTesting and Analysis CenterCollege of Chemistry and Materials ScienceHebei Normal UniversityShijiazhuang 050024China State key laboratory of Supramolecular Structure and Materials Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchun 130021China

Dimensional regulation in polyoxometalates is an effective strategy during the design and synthesis of polyoxometalates-based high proton conductors,but it is not available to ***,the precise regulation of dimensionality has been realized in an unprecedented gigantic molybdenum blue wheel family featuring pentagonal{(W)Mo5}motifs through optimizing the molar ratio of Mo/W,including[Gd_(2)Mo_(124)W_(14)O_(422)(H_(2)O)62]38-(0D-{Mo_(124)W_(14)},1),[Mo_(126)W_(14)O441(H_(2)O)51]^(70-)(1D-{Mo_(126)W_(14)}n,2),and[Mo_(124)W_(14)O_(430)(H_(2)O)50]60-(2D-{Mo_(124)W_(14)}n,3).Such important{(W)Mo5}structural motif brings new reactivity into gigantic Mo blue *** are different numbers and sites of{Mo2}defects in each wheel-shaped monomer in 1-3,which leads to the monomers of 2 and 3 to form 1D and 2D architectures via Mo-O-Mo covalent bonds driven by{Mo2}-mediated H_(2)O ligands substitution process,respectively,thus achieving the controllable dimensional *** expected,the proton conductivity of 3 is 10 times higher than that of 1 and 1.7 times higher than that of *** continuous proton hopping sites in 2D network are responsible for the enhanced proton conductivity with lower activation *** study highlights that this dimensional regulation approach remains great potential in preparing polyoxometalates-based high proton conductive materials.

关键词： polyoxometalate molybdenum blue wheels Mo/W mixed-addenda polyoxometalates dimensional regulation proton conduction