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Synthesis of Lanthanide Cryptates by Transmetalation Reaction

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Journal of Rare Earths 2005年第S1期23卷 543-546页

作者：胡学雷刘焕胡丹袁军陈中黄齐茂潘志权 Hubei Key laboratory of Novel chemical Reactor and Green chemical technology Wuhan Institute of Chemical Technology Wuhan 430073 China

New lanthanide cryptates [LnL](ClO_4)_3 (Ln=Eu 3+, Ce 3+, Pr 3+, Sm 3+, Gd 3+, Tb 3+; L=1, 4, 12, 15, 18, 26, 31, 39, 42, 43, 44-undecaazapentacyclo-[13.***.13.1 6, 10.1 20, 24.1 33, 37]-tetratetraconta-4, 6, 8, 10(44), 11, 18, 20, 22, 24(43), 25, 31, 33, 35, 37(42), 38-penta decaene) were synthesized by transmetalation reaction of lanthanide perchlorates with its barium cryptate which was obtained by [2+3] template condensation of tren with 2,6-diformylpyridine in the presence of barium perchlorate, and characterized by elemental analysis, IR and electrospray mass spectrum.

关键词： lanthanide cryptate transmetalation reaction synthesis rare earths

Electrosynthesis of hierarchical NiLa-layered double hydroxide electrode for efficient oxygen evolution reaction

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Journal of Energy Chemistry 2019年第6期28卷 125-129页

作者： Shan Jiang Yunke Liu Wenfu Xie Mingfei Shao State Key laboratory of chemical Resource Engineering Beijing University of Chemical Technology

Oxygen evolution reaction(OER) is a key process for electrochemical water splitting due to its intrinsic large overpotential. Recently, layered double hydroxides(LDHs), especially Ni Fe-LDH, have been regarded as highly performed electrocatalysts for OER in alkaline condition. Here we first present a new class of Ni La-LDH electrocatalyst synthesized by an electrochemical process for efficient water splitting. The as-prepared NiL a-LDH nanosheet arrays(NSAs) give remarkable electrochemical activity and durability under alkaline environments, with a low overpotential of 209 mV for OER to deliver a current density of 10 mA cm^-2, surpassing most of previous reported LDHs eletrocatalysts. The presence of NiLa-LDH in this work extends the studies about LDHs-based electrocatalysts, which will benefit the development of electrochemical energy storage and conversion systems.

关键词： Layered double hydroxides Oxygen evolution reaction Lanthanides Electrosynthesis

A series of rare earth coordination polymer constructed from paddle-wheel building blocks

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Journal of Rare Earths 2008年第5期26卷 633-637页

作者：郭广生刘阳春张佳郭洪猷 State Key laboratory of chemical Resource Engineering Beijing University of Chemical Technology

Three coordination polymers, Ln2（bpdc）3（phen）2（H2O）2 （Ln=Nd（1）, Eu（2）, and Tb （3）; bpdc=2,2＇-bipyridine-3,3＇-dicarboxylate; phen=1,10-phenanthroline）, were obtained by hydrothermal reaction of Ln2O3 with 2,2＇-bipyridine-3,3＇-dicarboxylate acid, and 1,10-phe- nanthroline. They were characterized by single-crystal X-ray diffraction, IR spectra, and photoluminescent spectra. The crystallographic data of 1-3 indicated that they were isostructural. Both complexes contained paddle-wheel building blocks, formed by bpdc and phen ligands. These paddle-wheel secondary building units （SBUs） were further connected to form two-dimensional （2-D） metal organic framework （MOF） networks by 2,2＇-bipyridine-3, and 3＇-dicarboxylate tinkers. A three-dimensional （3-D） supramolecular structure was formed by π-π aromatic interactions between adjacent 2-D infinite networks. Photoluminescent measurements indicated that europium compound 2 and terbium compound 3 were strong, red and green emitters, respectively.

关键词： hydrothermal reaction coordination polymer X-ray diffraction photoluminescence rare earths

Engineering zirconium-based metal-organic framework-801 films on carbon cloth as shuttle-inhibiting interlayers for lithium-sulfur batteries

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Frontiers of chemical Science and Engineering 2022年第4期16卷 511-522页

作者： Gaofeng Jin Jiale Zhang Baoying Dang Feichao Wu Jingde Li Hebei Provincial Key laboratory of Green chemical technology and High Efficient Energy Saving Tianjin Key Laboratory of Chemical Process SafetySchool of Chemical Engineering and TechnologyHebei University of TechnologyTianjin 300130China

Lithium-sulfur batteries have been regarded as the next-generation rechargeable batteries due to their high theoretical energy density and specific ***,the shuttle effect of lithium polysulfides has hindered the development of lithium-sulfur ***,a novel zirconium-based metal-organic framework-801 film on carbon cloth was developed as a versatile interlayer for lithium-sulfur *** interlayer has a hierarchical porous structure,suitable for the immobilization of lithium polysulfides and accommodating volume expansion on ***,the MOF-801 material is capable of strongly adsorbing lithium polysulfides and promoting their catalytic conversion,which can be enhanced by the abundant active sites provided by the continuous structure of the MOF-801 *** on the above advantages,the lithium-sulfur battery,with the proposed interlayer,delivers an initial discharge capacity of 927 mAh·g^(-1) at 1 C with an extremely low decay rate of 0.04%over 500 ***,a high area capacity of 4.3 mAh·cm^(-2) can be achieved under increased S loading.

关键词： lithium-sulfur batteries metal-organic framework-801 film interlayer shuttle effect Cite this article

Synthesis and characterization of uniform nanoparticles of γ-Mo_2N for supercapacitors

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中国有色金属学会会刊：英文版 2009年第3期19卷 620-625页

作者：李学良邢妍汪华王华林王维东陈祥迎 School of chemical Engineering Hefei University of Technology Anhui Key laboratory of Controllable chemical Reaction and Material chemical Engineering Hefei University of Technology

Uniform nanoparticles of molybdenum nitride were synthesized by temperature-programmed reaction(TPR) using MoO3 and ammonia as reactants. This material was characterized by X-ray diffractometry(XRD), transmission electron microscopy(TEM), scanning electron microcopy(SEM) and cyclic voltammetry(CV). Results show that the material consists of a pure phase of γ-Mo2N nanoparticles with average diameter of about 16 nm. The material presents a specific capacitance of 172 F/g in 1 mol/L H2SO4 electrolyte at a scan rate of 1 mV/s and the potential window is broadened to 1.1 V (-0.6 to 0.5 V). At the 6 000th cycle, the material remains 94.9% and 94.7% of the initial capacitance in 1 mol/L H2SO4 and KCl solution, respectively. A possible mechanism comprising surface control and diffusion control is proposed to explain the effect of scan rates on specific capacitance.

关键词：超级电容器纳米粒子 Mo2N 合成程序升温反应透射电子显微镜扫描电子显微镜 X射线衍射

Copolymerization of α-Methylstyrene and Styrene

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Chinese Journal of Polymer Science 2014年第8期32卷 986-995页

作者： Qian Liu Lian-ying Liu 马育红 Chang-wen Zhao 杨万泰 College of Material Science and Engineering Beijing University of Chemical Technology State Key laboratory of chemical Resource Engineering Beijing University of Chemical Technology

In this paper, the effects of temperature from 60 ℃ to 80 ℃ and the molar ratios in monomer feed on the copolymerization of α-methylstyrene （AMS） and styrene （St） were studied. The resulting copolymers, designated as PAS, were characterized by FTIR, GPC, NMR and TGA. When the reaction temperature was below 75 ℃, the molecular weights increased almost linearly as the evolution of the copolymerization. The phenomenon revealed that AMS could mediate the conventional free radical polymerization having some features of a controlled system. As the AMS/St = 50/50 （molar） in feed, the overall fraction of the AMS unit incorporated into the copolymer was as high as 42 mol%, the monomer conversion could be more than 90 wt% and the molecular weights could reach as high as 4400. However, since the styrene is more reactive than AMS, the AMS fraction in copolymer increased with the overall monomer conversion. The 13C-NMR revealed the products were random copolymers which had triads, such as -AMS-AMS-AMS-, -St-AMS-AMS- （-AMS-AMS-St-） and -St-AMS-St-. TGA curves demonstrated that the degradation temperature of the resulting copolymers went down from about 356.9 ℃ （0 mol% AMS） to 250.2 ℃ （42 tool% AMS）. This behavior demonstrated that there exist weak bonds in the AMS- containing sequences which could be used as potential free radical generators.

关键词： α-Methylstyrene Styrene Bulk polymerization Thermal decomposition.

Characterization, crystal structure and luminescence properties of a new europium(III) complex with macrocyclic ligand derived from 2,6-diformyl-4-methylphenol and diethylenetriamine

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Journal of Rare Earths 2008年第6期26卷 795-799页

作者：胡学雷陈中邱立赵元弟潘志权 Key laboratory of Green chemical Process of Ministry of Education-Hubei Key laboratory of Novel chemical Reactor and Green chemical technology Wuhan Institute of Technology The Key laboratory of Biomedical Photonics of Ministry of Education Huazhong University of Science and Technology

The title compound （13,27-dimethyl-3,6,9,17,20,23-hexaazatricyclo-[23.***.1.1^11,15]-triaconta-1 （29）,2,9,11,13,15（30）, 16,23,25,27- decaene-29,30-diol-N^3, N^6, N^9, O^29, O^30）-bis （nitrato-O,O＇）-europium （Ⅲ） nitrate hydrate （[EuL（NO3）2]（NO3）·H2O, L denotes the macrocyclic ligand） was prepared and characterized by elemental analysis, infrared spectra, and electrospray mass spectra. Its crystal and molecular structure was determined by X-ray diffraction. The crystal crystallized in the monoclinic system, space group C2/c with a=2.3757 （4） nm, b=1.4302（3） nm, c=1.9584（3） nm, β=91.654（5）°, M=818.60, V=6.651（2） nm^3, Z=8, D=1.635 g/cm, F（000）=3312, R=0.0542, wR=0.1045. The central ion Eu^3＋ was nine-coordinated in the coordinaton geometry of a distorted tricapped trigonal prism. The macrocycle was coordinated through two oxygen and three nitrogen atoms. Two nitrate are chelate in the opposite positions of the macrocycle, the third nitrate being ionic. At room temperature, excitation of the title complex gave rise to the characteristic emissions of the Eu^3＋ ion.

关键词： crystal structure lanthanide macrocycle luminescence rare earths

Bio-decomposition of rock phosphate containing pyrites by Acidithiobacillus ferrooxidans

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Journal of Central South University of technology 2007年第2期14卷 170-175页

作者：池汝安肖春桥黄晓慧王存文吴元欣 Hubei Key laboratory of Novel chemical Reactor and Green chemical technology Wuhan Institute of Technology

Leaching soluble phosphorus from rock phosphate containing pyrites by Acidithiobacillus ferrooxidans (A.f.) is feasible, and the reaction mechanism is as follows. Pyrites are oxidized by A.f. to produce H_2SO_4 and FeSO_4; the rock phosphate is decomposed by H_2SO_4, forming soluble phosphorus compounds; and Fe2+ from FeSO_4 is oxidized to Fe^3+, providing energy for the growth of A. f.. In this process, as H_2SO_4 is produced in the reaction, an acidic condition in the culture medium is formed, which benefits the growth of A. f. and aids both continuous oxidation of pyrites and leaching of soluble phosphorus from rock phosphate. The fraction of phosphorous leached can reach the largest in the presence of 1.0 g/L Fe^3+, 200 mg/L Mg^2+ and 400 mg/L NH_4^+. The optimal technological parameters on the fraction of phosphorous leached are as follows: the volume fraction of inocula of A. f., the mass ratio of pyrites to rock phosphate and the pH value are in ranges of 5%-25%, 3:1-5:1 and 1.8-2.2, respectively.

关键词： bio-deeomposition rock phosphate pyrites Acidithiobacillusferrooxidans

MONOMER REACTIVITY RATIO AND THERMAL PERFORMANCE OFα-METHYL STYRENE AND GLYCIDYL METHACRYLATE COPOLYMERS

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Chinese Journal of Polymer Science 2010年第3期28卷 323-330页

作者：梁淑君 Taiyuan Institute of technology State Key laboratory of chemical Resource Engineering Beijing University of Chemical Technology College of Materials Science and Engineering Beijing University of Chemical Technology

Synthesis and characterization of the copolymers （PAG） of α-methyl styrene （AMS） and glycidyl methacrylate （GMA） are presented. The copolymers of PAG were characterized by gel permeation chromatography （GPC）, Fourier transform infrared spectroscopy （FTIR）, nuclear magnetic resonance （^1H-NMR） and thermogravimetery （TG）. Based on the copolymer compositions determined by ^1H-NMR, the reactivity ratios of AMS and GMA were found to be 0.105 ± 0.012 and 0.883 ± 0.046 respectively by Kelen-Tudos method. TG revealed that thermal stability of the copolymers decreased with increasing the AMS content in the copolymers, which indicated that the degradation was mainly caused by the chain scission of AMS-containing structures. Under heating, the copolymers depolymerize at their weak bonds and form chain radicals, which could further initiate other chemical reactions.

关键词： Copolymerization α-Methyl styrene Glycidyl methacrylate Reactivity ratios Depolymerization