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Ultrastable nickel single-atom catalysts with high activity and selectivity for electrocatalytic CO_(2)methanation

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Nano Research 2023年第7期16卷 8987-8995页

作者： Ling-Chan Tian Jin-Nian Hu Yang Meng Jin-Xia Liang Chun Zhu Jun Li School of chemistry and Chemical Engineering Guizhou UniversityGuiyang 550025China department of chemistry and Guangdong Provincial Key Laboratory of Catalytic chemistry Southern University of Science and TechnologyShenzhen 518055China department of chemistry and Engineering Research Center of Advanced Rare-Earth Materials of Ministry of Education Tsinghua UniversityBeijing 100084China

Electrochemical conversion of CO_(2)into valuable hydrocarbon fuel is one of the key steps in solving carbon emission and energy ***,we report a non-noble metal catalyst,nickel single-atom catalyst(SAC)of Ni_(1)/UiO-66-NH_(2),with high stability and selectivity for electrochemical reduction of CO_(2)to CH_(4).Based on ab initio molecular dynamics(AIMD)simulations,the CO_(2)molecule is at first reduced into CO_(2)-when stably adsorbed on a Ni single atom with the bidentate coordination *** evaluate its activity and selectivity for electrocatalytic reduction of CO_(2)to different products(HCOOH,CO,CH3OH,and CH_(4))on Ni_(1)/UiO-66-NH_(2),we have used density functional theory(DFT)to study different reaction *** results show that CH_(4) is generated preferentially on Ni_(1)/UiO-66-NH_(2)and the calculated limiting potential is as low as-0.24 ***,the competitive hydrogen evolution reaction is unfavorable at the activation site of Ni_(1)/UiO-66-NH_(2)owing to the higher limiting potential of-0.56 ***,the change of Ni single atom valence state plays an important role in promoting CO_(2)reduction to CH_(4).This work provides a theoretical foundation for further experimental studies and practical applications of metal-organic framework(UiO-66)-based SAC electrocatalysts with high activity and selectivity for the CO_(2)reduction reaction.

关键词： single atom catalyst density functional theory CO_(2)reduction metal-organic framework electrocatalysis

Synthesis and Crystal Structure of [O-4,6-di-^tBu-C6H2-2-CH2-[C{N（CHCH）NMe}]3Y

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Chinese Journal of Structural chemistry 2011年第1期30卷 55-58页

作者：王志国沈琪刘思曼黄海霞周小力 department of chemistry and Chemical Engineering Mianyang Normal University College of chemistry and Chemical Engineering Suzhou University

The title complex L3Y（L = [O-4,6-di-tBu-C6H2-2-CH{CH（iPr2NCHCHN） }]） has been synthesized by the reaction of LiY[N（iPr） 2]4 with H2LCl and LiBu in a 1：3：2 molar ratio at 0 ℃ in THF,and characterized by single-crystal X-ray diffraction. It crystallizes in monoclinic,space group P21 with a = 14.3612（16） ,b = 14.7524（14） ,c = 16.898（2） ,β = 105.708（3） o,V = 3446.3（6） A^3,Mr = 1203.50,Z = 2,Dc = 1.160 Mg/m^3,μ（MoKα） = 0.90 mm^-1 and F（000） = 1296. The structure was refined to R = 0.050 and wR = 0.110 for 10213 observed reflections with I 〉 2σ（I） . The Y ion is coordinated to three phenoxo groups and three NHC ligands to form a distorted octahedral geometry. The temperature effect on the reaction leads to the 1,2-benzyl migration of NHC ligand to form the title complex.

关键词： organolanthanide N-aryloxo imidazolium crystal structure 1 2-benzyl migration yttrium

Ionic liquid-assisted hydrothermal synthesis of SnS nanoparticles:Electrode materials for lithium batteries,photoluminescence and photocatalytic activities

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Journal of Energy chemistry 2018年第3期27卷 806-812页

作者： K.N.Manukumar G.Nagaraju Brij Kishore C.Madhu N.Munichandraiah department of chemistry Siddaganga Institute of TechnologyTumkurKarnatakaIndia department of Inorganic and Physical chemistry Indian Institute of ScienceBangaloreKarnatakaIndiac department of Physics.Siddaganga Institute of Technology.Tumkur KarnatakaIndia

Tin mono-sulphide（Sn S） nanoparticles（Nps） have been successfully synthesised through ionic liquid assisted hydrothermal method using hydrated tin（II） chloride as a precursor, thiourea as sulphur source precursors using 2-Methoxy ethyl methyl imidazolium methane sulfonate ionic liquid as co-solvent. The Reitveld refinement on powder X-ray diffraction（PXRD） confirmed the presence of orthorhombic Sn S structure as major phase along with traces amount of Sn S2 and Sn2 S3. Diffuse reflectance spectrum studies revealed the energy band gap around 1.38 e V. TEM images confirmed the Sn S Nps with average particle size of 40 nm and HRTEM suggest good crystallinity. The electrochemical property for lithium storage behaviour shows an initial discharge capacity of 658 m Ah/g and it retains discharge capacity of 426 m Ah/g for 16 cycles, at current density 100 m A/g. The obtained results indicate that Sn S Nps to be one of the possible promising anode materials for next generation Lithium batteries. Photoluminescence study of Sn S Nps shows a strong green emission at 530 nm. Sn S Nps were also tested for the photocatalytic adsorption of methylene blue and Rhodamine B.

关键词： Nanoparticles Lithium-ion batteries Ionic liquids Ionothermal

Synthesis and Single-crystal X-ray Studies of (E)-ethyl 2-fluoro-2-(3-oxoisobenzofuran-1(3H)-ylidene) Acetate

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Chinese Journal of Structural chemistry 2013年第8期32卷 1139-1142页

作者： Muhammad Adeel Peter Langer Alexander Villinger department of chemistry Gomal University Dera Ismail KhanKPK Pakistan Institute of chemistry University of Rostock

The title compound （E）-ethyl 2-fluoro-2-（3-oxoisobenzofuran-1（3H）-ylidene） aceta- te was synthesized as an unexpected product by the reaction ofphthalyl dichloride with bis-silylenol ether, which is not in accordance with our previous studies. The title compound was characterized by single-crystal X-ray diffraction, 1H NMR, 13C NMR, 19F NMR, GCMS, HRMS and IR. The crystal （C12HgFO4, Mr = 236.19） belongs to the monoclinic system, space group P21/c, a = 19.1609（8）, b = 7.9831（3）, c = 13.7715（6） A, V= 2106.13（15） A3, Z= 8, Dx = 1.490 Mg m-3, MoKa radiation, 2 = 0.71073 A,μ = 0.12 mm-1, F（000） = 976, the final R = 0.025 and wR = 0.1300 for 4505 observed reflections with I〉 2σ（I）.

关键词： organo fluorine compounds crystal structure 1,3-bis-silylenol ether,phthalyl dichloride condensation reaction

Effects of Lanthanum on Formation and Bone-Resorbing Activity of Osteoclast-Like Cells

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Journal of Rare Earths 2004年第6期22卷 891-895页

作者：张金超张天蓝许善锦王夔于世凤杨梦苏 department of Chemical Biology School of Pharmaceutical Sciences Peking University department of chemistry College of Chemistry & Environmental Science Hebei University Baoding 071002 China department of Oral Pathology Stomatological Hospital Peking University Beijing 100081 China department of Biology and chemistry City University of Hong Kong Hon)g Kong

The effect of La^(3+) on formation of osteoclast-like cells in rabbit bone marrow cells induced by 1,25-dihydroxyvitamin D_3 and their bone-resorbing activity was evaluated by counting the number of tartrate resistant-acid phosphatase-positive [TRAP(+)] multi-nucleated cells and measuring the number and surface area of bone resorption pits with photomicrography and image analysis. The formation and morphological characteristics of osteoclast-like cells and bone resorption pits were observed under a phase contrast inverted microscope. La^(3+) promotes the formation of osteoclast-like cells at the concentration of 1.00×10^(-8)mol·L^(-1) compared with the control group(P0.05). La^(3+) at the concentration of 1.00×10^(-8)mol·L^(-1) also increases the number and surface area of the resorption pits(P<0.01), but inhibits the bone-resorbing activity dose-dependently(P<0.01)at higher concentrations(1.00×10^(-5), 1.00×10^(-6) and 1.00×10^(-7) mol·L^(-1)). These findings suggest that La^(3+) may promote or inhibit the formation and bone-resorbing activity of osteoclast-like cells depending on its concentration.

关键词： lanthanum osteoclast-like cells 1, 25-dihydroxyvitamin D_3 bone marrow cells bone resorption rare earths

Uniform arrays of gold nanoparticles with different surface roughness for surface enhanced Raman scattering

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Chinese Chemical Letters 2015年第11期26卷 1426-1430页

作者： Yan Zhang Lian-Meng Wang En-Zhong Tan Shi-He Yang Li-Dong Li Lin Guo School of chemistry and Environment Beihang University department of Mathematics and Physics Beijing Institute of Technology Petrochemical department of chemistry The Hongkong University of Science and Technology

Uniform arrays of coarse and smooth gold nanoparticles with diameter about 130 nm were successfully synthesized through seed-mediated growth method, separately. Scanning and transmission electron microscopy （SEM and TEM） and X-ray diffraction （XRD） have been used to study the formation and structure of the nanocomposites. The high enhancement factor for surface-enhanced Raman scattering of coarse and smooth gold nanoparticles were estimated to be about 3.1 × 10^6 and 2.0 × 10^6, respectively. It is evident that the coarse gold nanostructures has higher influence factor than the smooth gold nanostructures. Therefore, these unique properties of the coarse Au nanoparticles appear to be very Dromising for applications as high-performance SERS subsrrares.

关键词： NanoparticlesDifferent RoughnessSERS

Synthesis of Calix[4]arene Derivatives with NLO Properties

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Chinese Journal of chemistry 2006年第1期24卷 124-128页

作者：柏祝张超智陆国元刘芳 department of chemistry State Key Laboratory of Coordination Chemistry Nanjing University Nanjing Jiangsu 210093 China

The new chromophore compounds with NLO properties were prepared by Knoevenagel condensation from forrnyl or diformyl calix[4/arene and isophorone derivatives in the presence of piperidine and acetic acid, respectively. In these chromophore calix[4]arenes, the ring locked trienes were employed as the conjugation bridge and electron acceptor in D-π-A units. The NMR spectra demonstrated that they existed in a cone conformation and consequently non-conjugated D-π-A units could be oriented at nearly the same direction.

关键词： chromophore calixarene nonlinear optics conformation Knoevenagel condensation

THE CATALYTIC EFFECTS OF OXYGEN AND AMINES IN THE REDOX-INITIATED DIMERIZATION OF N-VINYLCARBAZOLE*

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Science China chemistry 1990年第3期33卷 267-275页

作者：王其华何国杰 department of chemistry University of Massachusetts/Boston Boston Massachusetts 02125 USA department of chemistry Zhongshan University Guangzhou 510275 PRC

The redox reaction between N-vinylcarbazole (NVC) and various oxidants including Ce(Ⅳ), Fe(Ⅲ)and benzoylperoxide in methanol proceeds via the initial formation of the NVC N-cation radical which in turn leads to the formation of the NVC cyclic dimer, trans-1,2-dicarbazylcyclobutane. Molecular oxygen and a few arylamines are able to accelerate the rate of the formation and increase the yield of the dimer. The mechanism of this process and the functions of oxygen and arylamines are presented as follows: The participation of molecular oxygen is to facilitate the dissociation of the resulting reduced metal ion and the NVC N-cation radical ion pair or charge transfer complex, thereby releasing the free NVC N-cation radical and increase the rate of the formation and yield of the dimer. The arylamine in this reaction between NVC and oxidants can be viewed as electron transfer agent between NVC and the oxidant. Because the amines are present in small amount relative to the oxidants and can be regenerated in process, it is essentially catalytic in nature.

关键词： Dimerization of N-vinylcarbazole redox reaction mechanism.

A Stereoselective Synthesis of Substituted Allyl Alcohol by Threecomponent Rection of Acetylenic Sulfone,Phenylselenomagnesium Bromide and Ketones

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Chinese Chemical Letters 2003年第9期14卷 887-888页

作者： Mei Hua XIE, Lu Ling WU, Xian HUANGdepartment of chemistry, Zhejiang University, Xi-xi Campus, Hangzhou 310028 department of chemistry, Anhui Normal University, Wuhu 241000 department of chemistry Zhejiang University Xi-xi Campus Hangzhou 310028 China department of chemistry Anhui Normal University Wuhu 241000 China

Phenylseleno and sulfonyl substituted allyl alcohols were synthesized stereoselectively by the three-component reaction of acetylenic sulfone, phenylselenomagnesium bromide and ketones in one-pot.

关键词： Acetylenic sulfone ketone allyl alcohol stereoselectivity.