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Proton‑Prompted ligand exchange to Achieve High‑Efficiency CsPbI_(3) Quantum Dot Light‑Emitting Diodes

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Nano-Micro Letters 2024年第6期16卷 53-62页

作者： Yanming Li Ming Deng Xuanyu Zhang Lei Qian Chaoyu Xiang Laboratory of Advanced Nano‑Optoelectronic Materials and Devices Qianwan Institute of CNITECHNingbo 315300People’s Republic of China Division of Functional Materials and Nanodevices Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201People’s Republic of China Zhejiang Provincial Engineering Research Center of Energy Optoelectronic Materials and Devices Ningbo Institute of Materials Technology&EngineeringChinese Academy of SciencesNingbo 315201People’s Republic of China Faculty of Electrical Engineering and Computer Science Ningbo UniversityNingbo 315211ZhejiangPeople’s Republic of China University of Nottingham Ningbo China Ningbo 315100People’s Republic of China

CsPbI_(3)perovskite quantum dots(QDs)are ideal materials for the next generation of red light-emitting ***,the low phase stability of CsPbI_(3)QDs and long-chain insulating capping ligands hinder the improvement of device *** in-situ ligand replacement and ligand exchange after synthesis were often difficult to ***,we proposed a new ligand exchange strategy using a proton-prompted insitu exchange of short 5-aminopentanoic acid ligands with long-chain oleic acid and oleylamine ligands to obtain stable small-size CsPbI_(3)*** exchange strategy maintained the size and morphology of CsPbI_(3)QDs and improved the optical properties and the conductivity of CsPbI_(3)QDs *** a result,high-efficiency red QD-based light-emitting diodes with an emission wavelength of 645 nm demonstrated a record maximum external quantum efficiency of 24.45%and an operational half-life of 10.79 h.

关键词： CsPbI_(3) perovskite quantum dots Light-emitting diodes ligand exchange Proton-prompted in-situ exchange

Rational design of smart adsorbent equipped with a sensitive indicator via ligand exchange:A hierarchical porous mixed-ligand MOF for simultaneous removal and detection of Hg^(2+)

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Nano Research 2021年第5期14卷 1523-1532页

作者： Liang Zhang Jing Wang Huiting Wang Wentao Zhang Wenxin Zhu Ting Du Yongsheng Ni Xianghong Xie Jing Sun Jianlong Wang College of Food Science and Engineering Northwest A&F UniversityYangling712100China Qinghai Key Laboratory of Qinghai-Tibet Plateau Biological Resources Northwest Institute of Plateau BiologyChinese Academy of SciencesXining810008China

The increasing accumulation of toxic mercury species in water environment has posed a serious health threat worldwide, making it inevitable to develop the versatile materials to achieve efficient prevention and remediation of mercury pollution. Guided by the solvent-assisted ligand exchange (SALE) approach, this work rationally constructed a mixed-ligand NH2-UiO-66-SH (NSU66) with hierarchical-pore structure by incorporating the thiol-rich ligands (H2DMBD) into the water-stable NH2-UiO-66 (NU66) precursor to act as a smart adsorbent equipped with sensitive detector for simultaneous sensing and removal of Hg2+. Unlike the traditional adsorbents, the as-prepared NSU66 not only exhibits a remarkable removal ability with fast capture rate (within 60.0 min), large uptake capacity (265.29 mg/g), and qualified selectivity, but also possesses satisfactory sensing capability, accompanied by low detection limit (3.50 × 10−2 µM), wide linear range (1.00–99.7 µM), high specificity, and strong anti-interference capability. The detection function plays a vital role in indicating the removal behavior and the pre-enrichment effect of adsorption process correspondingly improves the sensitivity of indicator. Notably, the sensing and trapping capabilities of NSU66 are significantly improved compared to the NU66, which stems from the delicate design of the mixed-ligand and hierarchical-pore structure. Furthermore, proven excellent stability and recyclability emphasize the feasibility of NSU66 in practical applications. These results suggest that the smart NSU66 adsorbent can serve as a favorable platform for early warning and guided removal of toxic Hg2+ in water.

关键词： Zr-MOF ligand exchange mixed-ligand and hierarchical-pore structure integration of detection and removal Hg^(2+)

Single atom Pd1/ZIF-8 catalyst via partial ligand exchange

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Nano Research 2023年第5期16卷 8003-8011页

作者： Xin Li Fengwei Zhang Xu Han Jun-Hao Wang Xiaoqin Cui Peng Xing Huan Li Xian-Ming Zhang Institute of Crystalline Materials Shanxi UniversityTaiyuan 030006China Country College of Chemistry&Chemical Engineering Key Laboratory of Interface Science and Engineering in Advanced MaterialMinistry of EducationTaiyuan University of TechnologyTaiyuan 030024China

A partial ligand exchange strategy for fabricating catalytically active single palladium site immobilized on zeolitic imidazolate framework-8(ZIF-8,Pd1/ZIF-8)is proposed in this *** one-step synthesis simply involves reacting Na_(2)PdCl_(4) with ZIF-8 in *** Cl ligands of Na_(2)PdCl_(4) exchanged with 2-methylimidazole(2-MeIm)of the framework,resulting in the anchoring Pd on the framework and dissociation of Zn into the *** whole synthesis is performed at ambient conditions and the crystalline integrity of ZIF-8 is well *** resulting Pd_(1)/ZIF-8 is extensively characterized by different techniques which confirm the proposed ***_(1)/ZIF-8 is also successfully applied in the size-selective semi-hydrogenation of alkynes.

关键词： single atom catalyst metal-organic frameworks ligand exchange hydrogenation

Enantioselective extraction of mandelic acid enantiomers based on chiral ligand exchange

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Journal of Central South University of Technology 2005年第2期12卷 123-128页

作者：唐课文黄可龙 Department of Chemistry and Chemical Engineering Hunan Institute of Science and Technology School of Chemistry and Chemical Engineering Central South University Changsha 410083 China

Based on the chiral ligand exchange, the distribution behavior of mandelic acid enantiomers, and the partition of Cu2+ at different pH values were studied in a water/alcohol two-phase system containing Cu2+ and N-n-（dodecyl-L-proline（A）.） The influences of the solvent sort, the pH value, the concentrations of Cu2+ and chiral ligand on the partition coefficient（K） and separation factor（α） were discussed. The experimental results show that the A formed has more stable ternary complex with D-mandelic acid enantiomer than with L-mandelic acid enantiomer. There is an important influence of the pH value on K and α. When the pH values are less than 3.5, the formation of binary complexes is thermodynamically unfavourable. K and α become maximum when pH values are above 3.5 and the molar ratio of the chiral ligand to Cu2+ is 2∶1.

关键词： ligand exchange extraction chiral separation mandelic acid enantiomers

Investigation of Performances and Mechanism of Fluoride Removal by Fe(Ⅲ)-Loaded ligand exchange Cotton Cellulose Adsorbent

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Wuhan University Journal of Natural Sciences 2005年第5期10卷 936-940页

作者： ZHAO Ya-ping LI Xiu-yan LIU Lu CHEN Fu-hua College of Environmental Science and Engineering Nankai University Tianjin 300071 China Department of Environmental Science and Technology East China Normal University Shanghai 200062 China

Novel adsorbent, Fe（Ⅲ）-loaded ligand exchange cotton cellulose adsorbent [Fe（Ⅲ） LECCA], was used to in vestigate the adsorption performances and mechanism of fluoride removal from aqueous solutions. The adsorbent was found to adsorb fluoride rapidly and effectively. The fluoride removal was influenced by pH. Adsorption mode followed first-order reaction at different temperature, theapparent adsorption activated energy Ea was 6.37 kJ·mol^-1, and adsorption enthalpy △H was 5.35 kJ·mol^-1. The adsorption enfluoride on adsorbent was 3.2 mmol·g^-1 （dry weight）. The maximal integer coordination ratio of fluoride with Fe（Ⅲ） LECCA was 3：1. The ligand exchange mechanism of adsorption was elucidated through chemical methods and IR spectral analysis.

关键词： fluoride Fe(Ⅲ)LECCA adsorption mechanism ligand exchange

Significance　of　ligand　exchange　Relating　to　Sulfate　in　Retarding　Acidification　of　Variable　Charge　Soils　Caused　by　Acid　Rain

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Pedosphere 1996年第1期6卷 11-22页

作者： WANGJINGHUA YUTIANREN InstituteofSoilScience AcademiasinicaNanjing210008China InstituteofSoilScience AcademiasinicaNanji

For the purpose of evaluating the role of ligand exchange of sulfate ions in retarding the rate of acidification of variable charge soils, the changes in pH after the addition of different amounts of HNO_3 or H_2SO_4 to representative soils of China were measured. A difrerence between pH changes caused by the two kinds of acids was observed only for variable charge soils and kaolinite, but not for consted charge soils and bentonite. The larger the proportion of H_2SO_4 in the HNO_3-H_2SO_4 mixture, the lower the calculated H￣+ ion activities remained in the suspension. The difference in H￣+ ion activities between H_2SO_4 systems and HNO_3 systems was larger for soils with a low base-saturation (BS) percentage than those with a high BS percentage. The removal of free iron oxides from the soil led to a decrease in the difference, while the coating of Fe_2O_3 ona bentonite resulted in a remarkable appearance of the difference. The effect of ligand exchange on the acidity status of the soil varied with the soil type. SurfaCe soils with a hash organic matter content showed a less pronounced effect of ligand exchange than subsoils did. It was estimated that when acid rain chiefly containing H_2SO_4 was deposited on variable charge soils the acidilication rate might be slower by 20%-40% than that when the acid rain chiefly contained HNO_3 for soils with a high organic matter content, and that the rate might be half of that caused by HNO_3 for soils with a low organic matter content, especially for latosols.

关键词： acid rain ligand exchange soil acidification sulfate adsorption variable charge soil

F?(H2O)+CH3I ligand exchange Reaction Dynamics

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Chinese Journal of Chemical Physics 2020年第2期33卷 210-216,I0003,I0039-I0040页

作者： Bjorn Bastian Tim Michaelsen Milan Oncák Jennifer Meyer Roland Wester Institut für Ionenphysik und Angewandte Physik Universitat InnsbruckTechnikerstraβe 256020 InnsbruckAustria

Single hydration of the gas phase F^-+CH3I→CH3F reaction allows to probe solvent effects on a fundamental nucleophilic substitution *** the same time,the addition of a solvent molecule opens alternative product ***,we present crossed beam imaging results on the dynamics of the F^-(H2O)+CH3I→[FCH3I]^-+H2O ligand exchange pathway at collision energies between 0.3 and 2.6 *** kinetic energies are constrained by the stability requirement of the weakly bound product *** implies substantial internal excitation of the water molecule and disfavors effcient energy redistribution in an intermediate complex,which is reflected by the suppression of low kinetic energies as collision energy *** 0.3 eV,internal nucleophilic displacement is important and is discussed in light of the competing nucleophilic substitution pathways that form I^- and I^-(H2O).

关键词： Reaction dynamics ligand exchange Microsolvation Crossed beams Velocity map imaging

Simultaneous removal of arsenate and fluoride from water by AI-Fe （hydr）oxides

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Frontiers of Environmental Science & Engineering 2014年第2期8卷 169-179页

作者： Junlian QIAO Zimin CUI Yuankui SUN Qinghai HU Xiaohong GUAN State Key Laboratory of Pollution Control and Resources Reuse College of Environmental Science and Engineering Tongji University Shanghai 200092 China State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology Harbin 150090 China

A1-Fe （hydr）oxides with different A1/Fe molar ratios （4：1, 1：1, 1：4, 0：1） were prepared using a co- precipitation method and were then employed for simultaneous removal of arsenate and fluoride. The 4A1 ： Fe was superior to other adsorbents for removal of arsenate and fluoride in the pH range of 5.0-9.0. The adsorption capacity of the A1-Fe （hydr）oxides for arsenate and fluoride at pH 6.50.3 increased with increasing A1 content in the adsorbents. The linear relationship between the amount of OH released from the adsorbent and the amount of arsenate or fluoride adsorbent by 4A1 ： Fe indicated that the adsorption of arsenate and fluoride by A1- Fe （hydr）oxides was realized primarily through quantita- tive ligand exchange. Moreover, there was a very good correlation between the surface hydroxyl group densities of A1-Fe （hydr）oxides and their adsorption capacities for arsenate or fluoride. The highest adsorption capacity for arsenate and fluoride by 4A1 ： Fe is mainly ascribed to its highest surface hydroxyl group density besides its largest pHpzc. The dosage of adsorbent necessary to remove arsenate and fluoride to meet the drinking water standard was mainly determined by the presence of fluoride since fluoride was generally present in groundwater at much higher concentration than arsenate.

关键词： A1-Fe (hydr)oxides groundwater adsorption hydroxyl group ligand exchange

Fabrication of recyclable Fe^(3+) chelated aminated polypropylene fiber for efficient clean-up of phosphate wastewater

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Frontiers of Chemical Science and Engineering 2023年第7期17卷 840-852页

作者： Shangyuan Zhao Fangjia Wang Rui Zhou Peisen Liu Qizhong Xiong Weifeng Zhang Chaochun Zhang Gang Xu Xinxin Ye Hongjian Gao Anhui Province Key Laboratory of Farmland Ecological Conservation and Pollution Prevention Engineering and Technology Research Center of Intelligent Manufacture and Efficient Utilization of Green Phosphorus Fertilizer of Anhui ProvinceCollege of Resources and EnvironmentAnhui Agricultural UniversityHefei 230036China Key Laboratory of JiangHuai Arable Land Resources Protection and Eco-restoration Ministry of Natural ResourcesCollege of Resources and EnvironmentAnhui Agricultural UniversityHefei 230036China Institute of Soil Science Chinese Academy of SciencesNanjing 210008China

Herein,a Fe^(3+)-loaded aminated polypropylene fiber has been reported as an efficient phosphate *** remarkable phosphate removal ability of the fiber is due to Fe^(3+)immobilization,and it demonstrates a maximum adsorption capacity of 33.94 mg·P·g^(–1).Adsorption experiments showed that the fiber is applicable over a wide pH range from 2 to ***,the adsorption kinetics and isotherm data were consistent with the pseudo-second-order and Langmuir adsorption models,*** adsorption equilibrium of the fiber for phosphate was reached within 60 min,indicating an efficient monolayer chemisorption ***,the adsorbent maintained prominent phosphate removal in the presence of competitive ions such as NO_(3)^(–)and Cl^(–),exhibiting high *** importantly,the fiber demonstrated excellent reusability(5 times)and low adsorption limit below 0.02 mg·P·g^(–1).In addition,the phosphate removal efficiency of the fiber can exceed 99%under continuous flow *** adsorption mechanism was studied by X-ray photoelectron spectroscopy,showing that the adsorption of phosphate on the fiber mainly depended on the chemical adsorption of the modified Fe^(3+).Overall,this study proves that the fiber possesses many advantages for phosphate removal,including high adsorption efficiency,lower treatment limit,good recyclability,and environmental friendliness.

关键词： phosphate adsorption aminated polypropylene fiber Fe^(3+) ligand exchange reusability