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Synthesis and Crystal Structure of 1D Cd-amine Coordination Polymer and Its Luminescent Properties

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Chemical Research in Chinese Universities 2014年第5期30卷 720-725页

作者： XU Mengying LIU Zhigang FAN Ruiqing GAO Song chen shuo YANG Yulin Department of Chemistry Harbin Institute of Technology Harbin 150001 P. R. China

A novel one dimension（1D） cadmium coordination polymer {[Cd（mpda）3]·2（NO3）}n（1） was synthesized via refluxing a mixture of tetradentate Schiff base ligand N,N＇-bis（2-pyridinylethylidene）phenylene-1,3-diamine（L） and Cd（NO3）2 in acetonitrile, whose structure was characterized by means of single crystal X-ray diffraction, FTIR spectroscopy, elemental analysis and proton nuclear magnetic resonance（1H NMR）. Center metal Cd（II） ion is six-coordinated by six nitrogen atoms from six different m-phenylenediamine（mpda）, giving rise to a [CdN6] octahe- dral coordination environment. The two adjacent cadmium centers are linked by three mpda molecules leading to the construction of 1D chain structure. The crystal structure is stabilized by N-H…O hydrogen bonds to form three-dimension supramolecule. Compound 1 exhibits intense yellow luminescence in solid state at 298 K（λem=554 nm）, which shows a blue shift at 77 K（ca. 147 nm）. Additionally, fluorescence characteristics of compound 1 were investigated in different solvents（polarity： DMSO〉CH3CN〉CH3OH〉CHC13〉toluene） at 298 and 77 K. The results show that the emission peak of compound 1 in solvent exhibits a slight bathochromic shift. However, the emission peaks of compound 1 in CH3OH and CHC13 are red shift compared with that in CH3CN. It is revealed that the lumi- nescence behavior of compound 1 depends on not only the polarity of solvent but also the hydrogen bonding proper- ties between solvent and solute. In addition, the emission peak of compound 1 in solution shows a red shift obviously at 77 K than that at 298 K（ca. 144-159 nm）, with the fluorescence lifetime increased at 77 K. The lifetime in DMSO at 77 K（r=12.470μs） was the longest one. The quantum yield of compoud 1 increases with increasing the polarity of solvent within a range of 1.8%-8.3 %.

关键词： Schiffbase Cd(II)-amine compound Luminescence Crystal structure

Exploiting the Direct Link in IRS Assisted NOMA Networks with Hardware Impairments

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Computer Modeling in Engineering & Sciences 2023年第7期136卷 767-785页

作者： Ziwei Liu Xinwei Yue shuo chen Xuliang Liu Yafei Wang Wanwei Tang Key Laboratory of Modern Measurement&Control Technology Ministry of EducationSchool of Information and Communication EngineeringBeijing Information Science and Technology UniversityBeijing100101China The Party Committee Office Yellow River Conservancy Technical InstituteKaifeng475001China Tangshan University Tangshan063000China

Hardware impairments(HI)are always present in low-cost wireless *** paper investigates the outage behaviors of intelligent reflecting surface(IRS)assisted non-orthogonal multiple access(NOMA)networks by taking into account the impact of ***,we derive the approximate and asymptotic expressions of the outage probability for the IRS-NOMA-HI *** on the asymptotic results,the diversity orders under perfect self-interference cancellation and imperfect self-interference cancellation scenarios are obtained to evaluate the performance of the considered *** addition,the system throughput of IRS-NOMA-HI is discussed in delay-limited *** obtained results are provided to verify the accuracy of the theoretical analyses and reveal that:1)The outage performance and system throughput for IRS-NOMA-HI outperforms that of the IRS-assisted orthogonal multiple access-HI(IRS-OMA-HI)networks;2)The number of IRS elements,the pass loss factors,the Rician factors,and the value of HI are pivotal to enhancing the performance of IRS-NOMAHI networks;and 3)It is recommended that effective methods of reducing HI should be used to ensure system performance,in addition to self-interference cancellation techniques.

关键词： Hardware impairments imperfect SIC intelligent reflecting surface non-orthogonal multiple access outage probability

Back contact interfacial modification mechanism in highly-efficient antimony selenide thin-film solar cells

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Journal of Energy Chemistry 2023年第5期80卷 256-264,I0007页

作者： Junhui Lin Guojie chen Nafees Ahmad Muhammad Ishaq shuo chen Zhenghua Su Ping Fan Xianghua Zhang Yi Zhang Guangxing Liang Shenzhen Key Laboratory of Advanced Thin Films and Applications Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong ProvinceCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060GuangdongChina Institute of Fundamental and Frontier Science University of Electronic Science and Technology of ChinaChengdu 610054SichuanChina Univ Rennes CNRSISCR(Institut des Sciences Chimiques de Rennes)UMR 6226Rennes F-35000France Institute of Photoelectronic Thin Film Devices and Technology and Tianjin Key Laboratory of Thin Film Devices and Technology Nankai UniversityTianjin 300350China

Antimony selenide(Sb_(2)Se_(3))is a potential photovoltaic(PV)material for next-generation solar cells and has achieved great development in the last several *** properties of Sb_(2)Se_(3)absorber and back contact influence the PV performances of Sb_(2)Se_(3)solar ***,optimization of back contact characteristics and absorber orientation are crucial steps in raising the power conversion efficiency(PCE)of Sb_(2)Se_(3)solar *** this work,MoO2was introduced as an intermediate layer(IL)in Sb_(2)Se_(3)solar cells,and comparative investigations were *** growth of(211)-oriented Sb_(2)Se_(3)with large grains was facilitated by introducing the MoO2IL with suitable *** MoO2IL substantially lowered the back contact barrier and prevented the formation of voids at the back contact,which reduced the thickness of the MoSe2interface layer,inhibited carrier recombination,and minimized bulk and interfacial defects in ***,significant optimization enhanced the open-circuit voltage(VOC)of solar cells from 0.481 V to 0.487 V,short-circuit current density(JSC)from 23.81 m A/cm^(2)to 29.29 m A/cm^(2),and fill factor from 50.28%to 57.10%,which boosted the PCE from 5.75%to 8.14%.

关键词： Sb_(2)Se_(3)solar cells MoO_(2)intermediate layer Back contact Defects

Hierarchical Interconnected NiMoN with Large Specific Surface Area and High Mechanical Strength for Efficient and Stable Alkaline Water/Seawater Hydrogen Evolution

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Nano-Micro Letters 2023年第9期15卷 520-535页

作者： Minghui Ning Yu Wang Libo Wu Lun Yang Zhaoyang chen Shaowei Song Yan Yao Jiming Bao shuo chen Zhifeng Ren Department of Physics and Texas Center for Superconductivity at the University of Houston(TcSUH) University of HoustonHoustonTX 77204USA Cullen College of Engineering and TcSUH University of HoustonHoustonTX 77204USA School of Materials Science and Engineering Hubei Normal UniversityHuangshi 435002HubeiPeople’s Republic of China Department of Electrical and Computer Engineering and TcSUH University of HoustonHoustonTX 77204USA

NiMo-based nanostructures are among the most active hydrogen evolution reaction(HER)catalysts under an alkaline environment due to their strong water dissociation ***,these nanostructures are vulnerable to the destructive effects of H_(2) production,especially at industry-standard current ***,developing a strategy to improve their mechanical strength while maintaining or even further increasing the activity of these nanocatalysts is of great interest to both the research and industrial ***,a hierarchical interconnected NiMoN(HW-NiMoN-2h)with a nanorod-nanowire morphology was synthesized based on a rational combination of hydrothermal and water bath ***-NiMoN-2h is found to exhibit excellent HER activity due to the accomodation of abundant active sites on its hierarchical morphology,in which nanowires con-nect free-standing nanorods,concurrently strengthening its structural stability to withstand H_(2) production at 1 A cm^(−2).Seawater is an attractive feedstock for water electrolysis since H_(2) generation and water desalination can be addressed simultaneously in a single *** HER performance of HW-NiMoN-2h in alkaline seawater suggests that the presence of Na+ions interferes with the reation kinetics,thus lowering its activity ***,benefiting from its hierarchical and interconnected characteristics,HW-NiMoN-2h is found to deliver outstanding HER activity of 1 A cm^(−2) at 130 mV overpotential and to exhibit excellent stability at 1 A cm^(−2) over 70 h in 1 M KOH seawater.

关键词： Hydrogen evolution reaction(HER) Nanoarchitecture NiMo catalysts Direct seawater electrolysis Nanostructural stability

Interface optimization and defects suppression via Na F introduction enable efficient flexible Sb_(2)Se_(3) thin-film solar cells

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Journal of Energy Chemistry 2024年第3期90卷 165-175,I0006页

作者： Mingdong chen Muhammad Ishaq Donglou Ren Hongli Ma Zhenghua Su Ping Fan David Le Coq Xianghua Zhang Guangxing Liang shuo chen Shenzhen Key Laboratory of Advanced Thin Films and Applications Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong ProvinceCollege of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060GuangdongChina State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures MOE Key Laboratory of New Processing Technology for Nonferrous Metals and MaterialsSchool of ResourcesEnvironment and MaterialsGuangxi UniversityNanning 530004GuangxiChina CNRS ISCR(Institut des Sciences Chimiques de Rennes)UMR 6226Universitéde RennesRennes F-35000France

Sb_(2)Se_(3) with unique one-dimensional(1D) crystal structure exhibits exceptional deformation tolerance,demonstrating great application potential in flexible ***,the power conversion efficiency(PCE) of flexible Sb_(2)Se_(3) photovoltaic devices is temporarily limited by the complicated intrinsic defects and the undesirable contact ***,a high-quality Sb_(2)Se_(3) absorber layer with large crystal grains and benign [hkl] growth orientation can be first prepared on a Mo foil *** NaF intermediate layer is introduced between Mo and Sb_(2)Se_(3),which can further optimize the growth of Sb_(2)Se_(3)thin ***,positive Na ion diffusion enables it to dramatically lower barrier height at the back contact interface and passivate harmful defects at both bulk and *** a result,the champion substrate structured Mo-foil/Mo/NaF/Sb_(2)Se_(3)/CdS/ITO/Ag flexible thin-film solar cell delivers an obviously higher efficiency of 8.03% and a record open-circuit voltage(V_(OC)) of 0.492 *** flexible Sb_(2)Se_(3) device also exhibits excellent stability and flexibility to stand large bending radius and multiple bending times,as well as superior weak light photo-response with derived efficiency of 12.60%.This work presents an effective strategy to enhance the flexible Sb_(2)Se_(3) device performance and expand its potential photovoltaic applications.

关键词： Sb_(2)Se_(3) Flexible solar cells NaF intermediate layer Interface optimization Defects suppression

Photodegradation of 2,4-D induced by NO_2^- in aqueous solutions: The role of NO_2

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Journal of Environmental Sciences 2014年第7期26卷 1383-1387页

作者： Chunyan Yu Hua Wang Xuan Liu Xie Quan shuo chen Jianlin Zhang Peng Zhang National Marine Environmental Monitoring Center School of Fisheries and Life Science Dalian Ocean University Key Laboratory of Industrial Ecology and Environmental Engineering Ministry of Education School of Environmental Science and TechnologyDalian University of Technology

To elucidate the effect of nitrite ion （NO2^-） on the photodegradation of organic pollutants, a 300 W mercury lamp and Pyrex tubes restricting the transmission of wavelengths below 290nm were used to simulate sunlight, and the photodegradation processes of 2,4-dichlorophenoxyacetic acid （2,4-D） with different concentrations of NO2^- in freshwater and seawater were studied. The effect of reactive oxygen species （ROS） on the photolysis of 2,4-D was also demonstrated using electron paramagnetic resonance （EPR）. The results indicated that the 2,4-D photolysis reaction followed the first-order kinetics in freshwater and seawater under different concentrations of NO2^-. Meanwhile, the photochemical reaction rate of 2,4-D increased with increasing concentration of NO2^-. When the concentration of NO2^- was lower than 23 mg/L, the photodegradation rate of 2,4-D in seawater was higher than that in freshwater. However, when the concentration of NO2^- was reached 230 mg/L, 2,4-D degradation slowed down in seawater. It was important to note that EPR spectra showed NO2 radical was generated in the NO5 solution under simulated sunlight irradiation, indicating that 2,4-D photodegradation could be induced by NO2. These results show the key role of NO2^- in photochemistry and are helpful for better understanding of the phototransformation of environmental contaminants in natural aquatic systems.

关键词： Nitrite ionPhotodegradation2 4-Dichlorophenoxyaceticacid (2 4-D)NO2^-

Recent Trends and Challenges with COVID-19—Africa,April 4,2020

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China CDC weekly 2020年第21期2卷 365-369页

作者： Xiaochun Wang shuo chen Feng Tan George F.Gao Chinese Center for Disease Control and Prevention BeijingChina Africa Centers for Disease Control and Prevention Addis AbabaEthiopia

Summary What is already known about this topic?Since the first COVID-19 confirmed case was reported,the current epidemic in Africa has rapidly *** is added by this report?As of April 4,2020,a total of 7,405 confirmed cases and 305 deaths had been reported from 51 countries across *** cumulative number of reported COVID-19 cases varied among the five regions of Africa,of which northern Africa reported the largest number of confirmed *** five countries with the highest number of cases are South Africa,Algeria,Egypt,Morocco,and *** are the implications for public health practice?

关键词： fir Africa COV

Conceptual design of energy-saving stripping process for industrial sour water

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Chinese Journal of Chemical Engineering 2020年第5期28卷 1277-1284页

作者： Hengjun Gai shuo chen Kaiqiang Lin Xiaowei Zhang Chun Wang Meng Xiao Tingting Huang Hongbing Song College of Chemical Engineering Qingdao University of Science and TechnologyQingdao 266042China

Sour water contains ammonia,carbon dioxide,and hydrogen sulfides,producing from oil refining,coking,and coal *** reduce the energy consumption in sour water stripping,a novel process is proposed which integrates with the bottom flashing mechanical vapor recompression heat pump(MVRHP)for treating such ***,Aspen PlusTM as a powerful set of chemical process simulation software is utilized to investigate the economy and feasibility of the novel *** of the results of two process simulations,it can be seen that it is possible to reduce the total annual cost by nearly 45%to adopt the novel process,despite the capital investment increase 45%more than the conventional ***,the provided conceptual design will play a guiding role in the industrialization of the process.

关键词： Energy saving Sour water stripping Thermal pump Conceptual design Coal gasification wastewater

Stable and Efficient Red Perovskite Light-Emitting Diodes Based on Ca^(2+)-Doped CsPbI_(3)Nanocrystals

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Research 2021年第1期2021卷 1192-1202页

作者： Wei Shen Jianbin Zhang Ruimin Dong Yanfeng chen Liu Yang shuo chen Zhan Su Yujun Dai Kun Cao Lihui Liu Shufen chen Wei Huang State Key Laboratory of Organic Electronics and Information Displays&Institute of Advanced Materials(IAM) Nanjing University of Posts&Telecommunications9 Wenyuan RoadNanjing 210023China Frontiers Science Center for Flexible Electronics(FSCFE) MIIT Key Laboratory of Flexible Electronics(KLoFE)Northwestern Polytechnical UniversityXi’an 710072China

α-CsPbI_(3)nanocrystals(NCs)with poor stability prevent their wide applications in optoelectronic ***^(2+)(1.00Å)as a new B-site doping ion can successfully boost CsPbI_(3)NC performance with both improved phase stability and optoelectronic *** a Ca^(2+)/Pb^(2+)ratio of 0.40%,both phase and photoluminescence(PL)stability could be greatly *** by increased tolerance factor,the cubic phase of its solid film could be maintained after 58 days in ambient condition or 4 h accelerated aging process at 120℃.The PL stability of its solution could be preserved to 83%after 147 days in ambient *** using UV light to accelerate aging,the T50 of PL could boost 1.8-folds as compared to CsPbI_(3)*** Ca^(2+)doping can dramatically decrease defect densities of films and reduce hole injection barriers,the red light-emitting diodes(LEDs)exhibited about triple enhancement for maximum the external quantum efficiency(EQE)up to 7.8%and 2.2 times enhancement for half-lifetime of LED up to 85 *** believe it is promising to further explore high-quality CsPbI_(3)NC LEDs via a Ca^(2+)-doping strategy.

关键词： properties ambient maintained