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Journal of Environmental Sciences 2023年第10期132卷 12-21页

作者： Naghmeh Bayati Saeed Dehghanpour department of chemistry Faculty of Physics and ChemistryAlzahra UniversityTehran ***Iran

In the presentwork,functional diamine groups into indium frameworks to synthesize cyclic carbonates from CO_(2)and epoxides with efficient catalytic activity in the absence of cocatalyst and solvent are reported for the first time.Crystalline porous materials(CPM)-5 modified with 1,2-phenylene diamine and ethylene diamine(CPM-5-PhDA and CPM-5-EDA),were prepared using a post-synthetic modification(PSM)method.The properties of the modified CPM-5 were characterized by powder X-ray diffraction(PXRD),Fourier transform infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS),N2-adsorption,scanning electron microscopy(SEM),CO_(2)adsorption,and temperature programmed desorption TPD methods.The presence of diamine groups as basic sites and indium Lewis acid sites in the framework structure were desirable for high catalytic activity.For a given catalyst weight,CPM-5-PhDA was the best candidate to appear with great catalytic activity and selectivity for the cycloaddition reaction at 100°C and1MPa CO_(2)under co-catalyst and solvent free conditions.CPM-5-PhDA alsowas found to afford large and bulky epoxides.The catalyst can be easily separated and reused five times without any decline in activity.

关键词： Cyclic carbonate Metal-organic frameworks CO_(2)fixation Post-synthesis Co-catalyst free

A Review of Metal-Organic Framework-Based Compounds for Environmental Applications

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Energy & Environmental Materials 2023年第3期6卷 47-76页

作者： Yongteng Qian Fangfang Zhang Dae Joon Kang Huan Pang School of chemistry and Chemical Engineering Yangzhou University department of physics Sungkyunkwan University department of Interdisciplinary Course of physics and chemistry Sungkyunkwan University

Metal-organic framework-based compounds have recently gained great attention because of their unique porous structure,ordered porosity,and high specific surface area.Benefiting from these superior properties,metalorganic framework-based compounds have been proven to be one of the most potential candidates for environmental governance and remediation.In this review,the different types of metal-organic framework-based compounds are first summarized.Further,the various environmental applications of metal-organic framework-based compounds including organic pollutant removal,toxic and hazardous gas capture,heavy metal ion detection,gas separation,water harvesting,air purification,and carbon dioxide reduction reactions are discussed in detail.In the end,the opportunities and challenges for the future development of metal-organic framework-based compounds for environmental applications are highlighted.

关键词： air purification environmental governance and remediation metal–organic framework organic pollutant removal toxic and hazardous gas capture

Selective enriching of trionic emission in a WS2-ZnO hybrid through type-Ⅱ band alignment

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Science China(Information Sciences) 2023年第6期66卷 63-70页

作者： Jin Feng LEONG Kim Yong LIM Xiao WU Qinghua XU Chorng Haur SOW Eng Tuan POH department of physics National University of Singapore department of chemistry National University of Singapore

Strategies to modulate the exciton dynamics in ultrathin two-dimensional(2D)semiconductors have always been an integral component in the bid towards improved optoelectronics and quantum photonic devices. The capability to non-destructively tune the relaxation dynamics, valley polarization, binding energies, and population ratio of various excitonic species has been well-sought for advanced applications.Through the rationale design of a WS2-ZnO hybrid platform, we present a distinct increment in the trion-toexciton ratio for WS2emission across a patterned heterostructure. The shift in dominant excitonic species arose due to the efficient charge segregation at the spatially confined interface of the type-Ⅱ heterostructure.Owing to the charge transfer process, the resultant emission profile presents up to four times amplification in the trion-to-exciton ratio, with temperature variable trion binding energies up to 59 meV. Since trions possess non-zero charge and spin degrees of freedom, the provision of a higher density of trions with increased binding stability would encourage new opportunities for reproducible optoelectronics and quantum emitters.

关键词： heterostructure trions type-II band alignment

Recent advances on the synthesis of natural pyrrolizidine alkaloids: alexine, and its stereoisomers

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Natural Products and Bioprospecting 2022年第1期12卷 26-40页

作者： Ghodsi Mohammadi Ziarani Negar Jamasbi Fatemeh Mohajer department of chemistry Faculty of Physics and ChemistryAlzahra UniversityP.O.Box ***TehranIran

Natural products have attracted the interest of the scientific community due to their importance and application.Alexine is a naturally polyhydroxylated pyrrolizidine alkaloid that is broadly found in plant sources and isolated from Alexa leiopetala.The biological properties such as glycosidase inhibitors,anti-virus,and anti-HIV activities,makes it interesting target for synthetical studies.This review reports different approaches and methodologies to the synthesis of alexine,and its stereoisomers as the target compounds in numerous studies.

关键词： Polyhydroxylated pyrrolizidine alkaloids Alexine Natural products Alexa leiopetala

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有机电子器件中的纳米接触实现高效空穴注入

Science Bulletin 2021年第9期66卷 875-879,M0003页

作者： Qingzhen Bian Chiara Musumeci Chuanfei Wang reas Skallberg Yongzhen Chen Zhangjun Hu EPeter Münger Kajsa Uvdal Mats Fahlman Olle Inganas Biomolecular and Organic Electronics Department of PhysicsChemistry and BiologyLinkoping UniversitySE-58183 LinkopingSweden Laboratory of Organic Electronics Department of Science and TechnologyLinkoping University60174 NorrkopingSweden Molecular Surface physics and Nano Science Department of PhysicsChemistry and BiologyLinkoping UniversitySE-58183 LinkopingSweden department of physics Chemistry and BiologyLinkoping UniversitySE-58183 LinkopingSweden

电极与半导体之间的欧姆接触是实现高效有机电子器件的关键.本文通过将DNA/表面活性剂复合物与双极性电子聚合物混合,获得了一种可印刷的杂化界面传输材料.研究发现DNA/表面活性剂复合物与导电聚合物之间可以进行有效的电荷转移,而纳米... 详细信息

电极与半导体之间的欧姆接触是实现高效有机电子器件的关键.本文通过将DNA/表面活性剂复合物与双极性电子聚合物混合,获得了一种可印刷的杂化界面传输材料.研究发现DNA/表面活性剂复合物与导电聚合物之间可以进行有效的电荷转移,而纳米尺寸的发光二极管证明传输材料与导电聚合物间的纳米接触有助于电荷的传输和注入.该新型材料可应用于高效有机发光二极管、太阳能电池和场效应晶体管.

关键词：有机发光二极管场效应晶体管空穴注入有机电子器件欧姆接触导电聚合物新型材料传输材料

Enhancing visible-light photocatalytic activity of α-Bi_2O_3 via non-metal N and S doping

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Chinese physics B 2014年第3期23卷 560-565页

作者：尚军高远郝维昌井溪信会菊王亮冯海凤王天民 Center of Materials physics and chemistry and department of physics Beihang University

In recent years, some important research indicated that the visible-light activity of photocatalysts could be enhanced via incorporating p-block non-metal elements into the lattice. In this paper, we investigated the electronic structures of pure and different non-metal （C, N, S, F, Cl, and Br） doped α-Bi2O3 using first-principles calculations based on the density functional theory. The band structures, the electronic densities of states, and the effective masses of electrons and holes for doped α-Bi2O3 were obtained and analyzed. The N and S dopings narrowed the band gap and reduced the effective mass of the carriers, which are beneficial for the photocatalytic performance. The theoretical predication was further confirmed by the experimental results.

关键词： α-Bi2O3 first-principles calculation non-metal doping photocatalytic performance

Rare-earth single atom based luminescent composite nanomaterials:Tunable full-color single phosphor and applications in WLEDs

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Nano Research 2022年第4期15卷 3594-3605页

作者： Shan Bao Haiyue Yu Guoyang Gao Hongyang Zhu Dingsheng Wang Peifen Zhu Guofeng Wang Key Laboratory of Functional Inorganic Material chemistry Ministry of EducationSchool of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080China School of physics and Electronic Engineering Linyi UniversityLinyi 276005China department of chemistry Tsinghua UniversityBeijing 100084China department of physics and Engineering physics The University of TulsaTulsaOK 74104USA

High-quality single-component white phosphors are instrumental in realizing high-efficiency devices.Rare earth fluorides and carbon quantum dots have great potential in the white light-emitting diode(WLED)field due to their unique advantages.Here,Rare-earth single atom based NaGdF4:Tb^(3+)/Eu^(3+)@C:N/Eu^(3+)single phosphor with tunable full-color luminescence was reported.The results of density functional theory(DFT)calculation and experimental characterization show that C atoms cannot be replaced by Eu^(3+),but C atoms are more favorable for anchoring Eu^(3+)single atoms.The DFT was employed to optimize the structures of the C:N/Eu^(3+)and NaGdF4:Tb^(3+)/Eu^(3+),and calculate the work function,optical properties,and charge density difference.The obtained tunable full-color single phosphor can emit stable light from blue to red or even white.The constructed WLED devices also have stable and excellent color performance,that is,a color rendering index of up to 95 and a lower color temperature,and it has broad application possibilities in WLEDs.

关键词： single atoms luminescence single phosphor white light-emitting diodes

Down-conversion characteristics of Eu3+ doped M2Y2Si2O9(M=Ba, Ca, Mg and Sr) nanomaterials for innovative solar panels

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Progress in Natural Science:Materials International 2019年第4期29卷 457-465页

作者： Suman Sheoran Vachan Singh Sitender Singh Sonika Kadyan Jasbir Singh Devender Singh department of chemistry Maharshi Dayanand University department of physics Government College

Down-conversion properties of Eu3+doped M2Y2Si2O9(M=Ba,Ca,Mg,Sr) phosphors have been investigated in detail.These phosphors were synthesized via the simple,fast and cost-effective sol-gel technique at a temperature of 950℃.Color coordinates and emission color can be altered by the varying concentration of dopant ion in Ca2Y2Si2O9phosphor.Optimum luminescence intensity was obtained when doping 0.03 mol of Eu3+ion.Using the excitation wavelength of 395 nm,these silicates showed strong red color,pure and sharp spectral peaks in visible region due to ~5 D0→F1-3transitions of Eu3+present in the lattice.Effect of reaction temperature on luminescence was also analyzed for these phosphors.The sharp peaks in the X-ray diffraction pattern indicated the high crystallinity of prepared phosphors.Ca2Y2Si2O9has shown an orthorhombic crystal structure.The FTIR results confirmed the metal-oxygen vibrational modes available in the range of 400-1600 cm-1.Transmission electron microscopy images have revealed that the variation of alkaline earth metal provided a very different crystal structure.Excellent down conversion response of these phosphor materials can provide a great significance in the application of the coming solar devices.

关键词： M2Y2Si2O9:Eu3+ Phosphor Sol-gel Lattice Solar devices

Structure Elucidation and Biological Screening of Bis(4-{[(E)-(2-Hydroxybenzylidene)amino]methyl}-cyclohexane-carboxylato-O)-triaqua-cadmium

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Chinese Journal of Structural chemistry 2018年第6期37卷 871-877页

作者： MUHAMMAD Danish SABA Akbar MUHAMMAD Nawaz Tahir MUHAMMAD Naeem Ahmed RABIA Ayub Butt MUHAMMAD Asam Raza MUHAMMAD Ashfaq department of chemistry University of Gujrat department of physics University of Sargodha department of chemistry University of Azad Jammu and Kashmir

Using a bidentate ligand, a Schiff base 4-（{[（Z）-（2-hydroxyphenyl）methyldene]amino}methyl）cyclohexanecarboxylic acid, complex I（ML2, where M = Cd（Ⅱ）） was synthesized and characterized by IR spectroscopy and X-ray crystallography. It crystallizes in monoclinic system, space group C2/c, M_r = 685.04, 0.34 mm × 0.26 mm × 0.14 mm, a = 54.050（3）, b = 6.1220（3）, c = 9.5081（5） A, β = 90.229（2）°, Z = 4, C_（30） H_（40） CdN_2 O_9 and V = 3146.2（3） A^3. Complex I was screened for its bactericidal activity against four bacterial strains Chromohalobactersalexigens, Chromohalobacterisraelensis, Halomonashalofila and Halomonassalina and fungicidal activity against Aspergillusnigerand Aspergillusflavus. Antimicrobial activity results showed that the synthesized complex displayed good anti-fungal activity against two fungal strains. It was found to be inactive against four different bacterial strains analyzed and was negative for bactericidal effect.

关键词： Schiff base tranexamic acid Cd XRD fungicidal activity bactericidal activity

Hydrothermal Syntheses,Crystal Structures and Characteristics of Two New Isostructural Ni(Ⅱ)Coordination Polymers

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Chinese Journal of Structural chemistry 2016年第11期35卷 1764-1769页

作者：赵恩晓李飞飞赵丹 Department of Physics and Chemistry Henan Polytechnic University

Two new isostructure nickel（Ⅱ） coordination polymers, [Ni2（5-Me-ip）（1,2- Bie）（H2O）2]n （1） and [Ni2（5-Br-ip）（1,2-Bie）（H2O）2]n （2）（5-Me-H2ip = 5-methylisophthalic acid, 5-Br-H2ip = 5-mromoisophthalic acid, 1,2-Bie = 1,2-bis（imidazole）ethane）, have been synthesized and structurally characterized by single-crystal X-ray diffraction. The result shows that complexes 1 and 2 crystallize in orthorhombic system, space group Pna21 with a = 16.3602（13）, b = 10.1465（8）, c = 21.8803（17）A^°, V = 3632.1（5） A^°3, Z = 4, Dc = 1.525 g/cm3, F（000） = 1728, R = 0.0292 and wR = 0.0668 for 6646 observed reflections （I 〉 2σ（I）） for complex 1 and a = 16.409（3）, b = 10.1625（17）, c = 21.918（4）A^°, V = 3654.9（11） A^°3, Z = 4, Dc = 1.752 g/cm^3, F（000） = 1936, R = 0.0309 and wR = 0.0600 for 6809 observed reflections （I 〉 2σ（I）） for complex 2. They both feature zigzag 2D layer structures, which are further staked along the a-axis through π…π and hydrogen interactions to form 3D supramolecular structures.

关键词： crystal structure coordination polymer 5-bromoisophthalic acid,1,2-bis（imidazole）ethane