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Synthesis, characterization and thermostability of tris(2,2,6,6-tetramethyl-3,5- heptanedionato)yttrium(Ⅲ)

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Journal of Rare Earths 2012年第10期30卷 1041-1047页

作者：张腾古宏伟丁发柱屈飞戴少涛 Key Laboratory of applied superconductivity Institute of Electrical EngineeringChinese Academy of Sciences

The metal-organic chemical vapor deposition （MOCVD） technique is a promising process for high temperature superconductor YBa2Cu3O7-δ （YBCO） preparation. In this technique, the purity, evaporation characteristics and thermostability of adopted precursors will de- cide the quality and reproducible results of YBCO film. In the present report, tris（2,2,6,6-tetramethyl-3,5-heptanedionato）yttrium（III）（Y（TMHD）3） was synthesized by the interaction of yttrium nitrate hydrate with TMHD in methanol solution, and its structure was identified by FTIR, 1H NMR, 13C NMR and EI-MS spectroscopy. Subsequently, the thermal property and the kinetics of decomposition were system- atically investigated by non-isothermal thermogravimetric analysis methods （TGA） at different heating rates in streams of N2, and the average apparent activation energy of evaporation process was evaluated by the Ozawa, Kissinger and Friedman methods. The possible conversion function was estimated through the Coats-Redfern method to characterize the evaporation patterns and followed a phase boundary reaction mechanism by the contracting area equation with average activation energy of 88.9 kJ/mol.

关键词： Y(TMHD)3 metal-organic chemical vapor deposition (MOCVD) synthesis thermostability rare earths

Synthesis, characterization, and thermostability of bis(2,2,6,6-tetramethyl-3,5-heptanedionato)barium(Ⅱ)

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Rare Metals 2013年第1期32卷 67-74页

作者： Teng Zhang Hong-Wei Gu Fa-Zhu Ding Fei Qu Shao-Tao Dai Key Laboratory of applied superconductivity Institute of Electrical Engineering Chinese Academy of Sciences

The metal-organic chemical vapor deposition （MOCVD） technique is a promising process for high-tem- perature superconductor YBa2Cu307_6（YBCO） preparation. In this technique, it is a challenge to obtain barium precursors with high volatility. In addition, the purity, evaporation characteristics, and thermostability of adopted precursors in whole process will decide the quality and reproducible results of YBCO film. In the present report, bis（2,2,6,6-tetramethyl- 3,5-heptanedionato）barium（II）（Ba（TMHD）2） was synthe- sized, and its structure was identified by PTIR, 1H NMR, 13C NMR, and ESI-MS spectroscopy. Subsequently, the thermal properties and the kinetics of decomposition were systemati- cally investigated by nonisothermal thermogravimetric anal- ysis methods. Based on the average apparent activation energy evaluated by the Ozawa, Kissinger, and Friedman methods, the volatilization process was discussed, and all results show that Ba（TMHD）2 is unstable and highly sensitive to the change of temperature during the whole evaporation process. There- fore, it is very important to choose suitable volatilization technology and conditions for avoiding Ba（TMHD）2 break- down （or thermal aging） during MOCVD process. Subse- quently, the possible conversion function is estimated through the Coats-Redfern method to characterize the evaporation patterns and follows a phase boundary reaction mechanism by the contracting surface equation with average activation energy of 118.7 ***1-1.

关键词： Ba(TMHD)2 Metal-organic chemical vapordeposition (MOCVD) Synthesis Thermostability

Observation of Impurity Accumulation After Hydrogen Multi-Pellet Injection in Large Helical Device

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Plasma Science and Technology 2013年第3期15卷 230-234页

作者：董春凤 Shigeru MORITA Motoshi GOTO 王二辉 Gen MOTOJIAMA Izumi MURAKAMI Ryuichi SAKAMOTO Norimasa YAMAMOTO National institute for Fusion Science Department of Fusion Science Graduate University for Advanced Studies Center of applied superconductivity & Sustainable energy Research Chubu University

Impurity accumulation is studied for neutral beam-heated discharges after hydrogen multi-pellet injection in Large Helical Device （LHD）. Iron density profiles are derived from radial profiles of EUV line emissions of FeXV-XXIV with the help of the collisional-radiative model. A peaked density profile of Fe2a＋ is simulated by using one-dimensional impurity transport code. The result indicates a large inward velocity of -6 m/s at the impurity accumulation phase. However, the discharge is not entirely affected by the impurity accumulation, since the concentration of iron impurity, estimated to be 3.3x10-5 to the electron density, is considerably small. On the other hand, a flat profile is observed for the carbon density of C6＋, which is derived from the Zeff profile, indicating a small inward velocity of -1 m/s. These results suggest atomic number dependence in the impurity accumulation of LHD, which is similar to the tokamak result.

关键词： impurity accumulation EUV spectrometer inward velocity

Synthesis,characterization,and thermostability of bis(2,2,6,6-tetramethyl-3,5-heptanedionato)copper(Ⅱ)

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Rare Metals 2012年第4期31卷 343-349页

作者： ZHANG Teng,GU Hongwei,DING Fazhu,QU Fei,and DAI Shaotao Key Laboratory of applied superconductivity,institute of Electrical Engineering,Chinese Academy of Sciences,Beijing 100190,China Key Laboratory of applied superconductivity Institute of Electrical Engineering Chinese Academy of Sciences Beijing China

Owing to the adaptability to large scale processing,excellent composition control and film uniformity,the metal-organic chemical vapor deposition（MOCVD） technique is a promising process for high-temperature superconductor YBa;Cu;O;（YBCO） *** this technique,the evaporation characteristics and thermostability of adopted precursors in whole process will decide the quality and reproducible results of YBCO *** the present report,bis（2,2,6,6-tetramethyl-3,5-heptanedionato）copper（II）(Cu（TMHD）;) was synthesized by the interaction of copper acetate hydrate with TMHD in methanol solution,and its structure was identified by FTIR,1 H NMR,and EI-MS ***,thermal property and the kinetics of decomposition were systematically investigated by nonisothermal thermogravimetric analysis methods（TGA） at different heating rates in streams of N;,and the average apparent activation energy of evaporation process was evaluated by the Ozawa,Kissinger,and Friedman *** possible conversion function was estimated through the Coats-Redfern method to characterize the evaporation patterns and followed a phase boundary reaction mechanism by the contracting area equation with average activation energy of 85.1 kJ·mol;.

关键词： Cu(TMHD)_2 metal-organic chemical vapor deposition(MOCVD) synthesis thermostability

Boosting charge extraction and efficiency of inverted perovskite solar cells through coordinating group modification at the buffer layer/cathode interface

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Nano Research 2025年第1期18卷 415-423页

作者： Zhiqing Liang Ziqiu Ren Ziyu Wang Nan Yan Ling Li Bo Zhang Yanlin Song College of Chemistry Zhengzhou UniversityZhengzhou 450052China Key Laboratory of applied Surface and Colloid Chemistry Ministry of Education Shaanxi Key Laboratory for Advanced Energy DevicesShaanxi Engineering Lab for Advanced Energy Technology School of Materials Science and EngineeringShaanxi Normal UniversityXi’an 710119China Key Laboratory of Green Printing Institute of ChemistryChinese Academy of Sciences(ICCAS)Beijing Engineering Research Center of Nanomaterials for Green Printing TechnologyNational Laboratory for Molecular Sciences(BNLMS)Beijing 100190China

In inverted perovskite solar cells (PSCs),effective modification of the interface between the metalcathode and electron transport layer (ETL) is crucial forachieving high performance and stability. Herein, sulfonatedbathocuproine, commonly known as disodium bathocuproinedisulfonate (BCDS), was employed as a cathode buffer layerto address the interfacial issues at the [6,6]-phenyl-C61-butyricacid methyl ester (PCBM)/Ag interface. BCDS possesses theability to form coordinate bonds with Ag electrodes. Theutilization of the BCDS buffer layer enhanced the chargeextraction capability at the cathode interface whilesimultaneously achieving interfacial defect passivation,improving interfacial contact and increasing the built-in electricfield. Consequently, a power conversion efficiency (PCE) of25.06% was achieved. Furthermore, owing to the excellent filmforminguniformity of BCDS on PCBM, the stability of thedevice was also improved. After storage in dry air for morethan 2000 h, the device maintained 96% of its initial efficiency. This work underscores the remarkable potential of tailoringcoordination groups to enhance charge extraction efficiency at the ETL-cathode interface, unveiling a promising newfrontier in buffer layer development and performance optimization strategies for PSCs.

关键词： perovskite solar cells buffer layer bathocuproine disulfonate coordination group modification electron transport layer(ETL)-cathode interface

Microstructure evolution of Nb_3Sn superconductors during diffusion treatment by bronze route

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Rare Metals 2012年第5期31卷 446-450页

作者： CHENG Junsheng WANG Qiuliang WANG Hui DAI Yinming Key Laboratory of applied superconductivity Institute of Electrical Engineering Chinese Academy of Sciences Beijing 100190 China

The element diffusion process of Nb_3Sn superconductors by bronze route was studied using X-ray diffraction, scanning electron microscopy and energy dispersive spectroscopy. The critical current of superconductors was measured by four-point method. The results show that a diffusion layer has formed around the boundaries between the filaments and bronze matrix after 15 h heat treatment. The diffusion layer thickness keeps stable after heat treatment duration of 50~75 h. The stable and solid Nb 3 Sn layer is obtained in the sample after 100 h heat treatment. Excessive heat treatment would induce superconductivity degeneration because of superconductor grain coarsening. The characteristics of the element diffusion process were discussed. The diffusion of tin atom is the governing factor in diffusion. In this study, Nb_3_Sn superconductors with good superconducting property were fabricated successfully at 670 °C after 100h heat treatment.

关键词： Nb_3Sn diffusion treatment bronze route critical current

energy-saving Superconducting Magnetic energy Storage(SMES)Based Interline DC Dynamic Voltage Restorer

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CSEE Journal of Power and energy Systems 2022年第1期8卷 238-248页

作者： Xiaoyuan Chen Qi Xie Xingming Bian Boyang Shen institute of applied superconductivity and energy efficiency School of EngineeringSichuan Normal UniversityChengdu 610101China State Key Laboratory of Alternate Electrical Power System with Renewable energy Sources North China Electric Power UniversityBeijing 102206China Electrical Engineering Division Department of EngineeringUniversity of CambridgeCambridge CB30FAUnited Kingdom

The fast-response feature from a superconducting magnetic energy storage(SMES)device is favored for suppressing instantaneous voltage and power fluctuations,but the SMES coil is much more expensive than a conventional battery energy storage *** order to improve the energy utilization rate and reduce the energy storage cost under multiple-line power distribution conditions,this paper investigates a new interline DC dynamic voltage restorer(IDC-DVR)scheme with one SMES coil shared among multiple compensating *** this new concept,an improved current-voltage(I/V)chopper assembly,which has a series of input/output power ports,is introduced to connect the single SMES coil with multiple power lines,and thereby satisfy the independent energy exchange requirements of any line to be ***,if two or more power lines have simultaneous compensating demands,the SMES coil can be selectively controlled to compensate the preferable line according to the priority order of the *** feasibility of the proposed scheme is technically verified to maintain the transient voltage stability in multiple-line voltage swell and sag cases caused by either output voltage fluctuations from external power sources or power demand fluctuations from local sensitive *** simulation results provide a technical basis to develop a cost-effective SMES-based IDC-DVR for use in various DC distribution networks.

关键词： DC distribution dynamic voltage restorer(DVR) interline DC dynamic voltage restorer superconducting magnetic energy storage(SMES) transient voltage stability

Application of high magnetic fields in advanced materials processing

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Chinese Science Bulletin 2006年第24期51卷 2944-2950页

作者： MA Yanwei XIAO Liye YAN Luguang applied superconductivity Laboratory Institute of Electrical Engineering Chinese Academy of Sciences Beijing 100080 China

Recently,steady magnetic fields avail-able from cryogen-free superconducting magnets open up new ways to process materials. In this paper,the main results obtained by using a high magnetic field to process several advanced materials are re-viewed. These processed objects primarily include superconducting,magnetic,metallic and nanome-ter-scaled materials. It has been found that a high magnetic field can effectively align grains when fab-ricating the magnetic and non-magnetic materials and make inclusions migrate in a molten metal. The mechanism is discussed from the theoretical view-point of magnetization energy.

关键词：高磁场磁化力先进材料材料加工

Synthesis, characterization and thermostability of barium β-diketonate with tetraethylenepentamine ligand

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Rare Metals 2012年第6期31卷 566-572页

作者： ZHANG Teng, GU Hongwei, DING Fazhu, QU Fei, and DAI Shaotao Key Laboratory of applied superconductivity, institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100190, China Key Laboratory of applied superconductivity Institute of Electrical Engineering Chinese Academy of Sciences Beijing China

The metal-organic chemical vapor deposition (MOCVD) technique is a promising process for high-temperature superconductor YBa2Cu3O7-δ(YBCO) preparation. In this technique, it is a challenge to obtain barium precursors with high volatility. In addition, the purity, evaporation characteristics and thermostability of adopted precursors in the whole process would decide the quality and reproducible results of YBCO film. In the present report, the barium precursor containing 2,2,6,6-tetramethylheptane-3,5-dionate and tetraethylenepentamine ligands (Ba(TMHD)-tetraen) was synthesized and identified by FTIR, 1H NMR, 13C NMR and ESI-MS spectroscopy. Subsequently the thermal property and the kinetics of decomposition were systematically investigated by combining non-isothermal thermogravimetric analysis methods (TGA), Ozawa, Kissinger and Friedman methods. On the basis of the apparent activation energy of the evaporation process, the thermostability and evaporation characteristics of the precursors were discussed. All results show that Ba(TMHD)-tetraen has higher volatility than Ba(TMHD)2, but it is unstable and highly sensitive to the change of temperature during the whole evaporation process. Therefore, it is very important to choose suitable volatilization technology and conditions for avoiding Ba(TMHD)-tetraen breakdown (or thermal aging) during the MOCVD process.

关键词： MOCVD barium precursor synthesis thermostability