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Science China Chemistry 2025年

作者： Lei Gu Xing Li Chao Wu Yang Feng Chunming Yang Lin Song Frontiers Science Center for Flexible Electronics Institute of Flexible Electronics Northwestern Polytechnical University Shanghai synchrotron radiation facility Shanghai Advanced Research Institute Chinese Academy of Sciences

Inverted perovskite solar cells （PSCs） have received great attention owing to the high certificated power conversion efficiency（PCE） reaching 26.7%. However, interfacial charge recombination is far superior to perovskite bulk charge recombination due to the use of fullerenes and their derivatives in inverted perovskite solar cells, which induces devastating open circuit voltage（VOC） losses. For this reason the present work attempts to use 4-chloropiperidine hydrochloride for the upper surface modification of perovskite to construct a quasi-two-dimensional （2D） structure with suitable 2D layer widths （n=2, 3 dominant）,which has a smaller electron carrier transport barrier without sacrificing short-circuit current （JSC） in the device. This strategy effectively passivates the interfacial defect states while promoting energy level alignment to achieve carrier dissociation and equilibrium transport at the interface, which in turn resulted in improved fill factor （FF）. In addition, additional energy levels are provided by 2D perovskites to collect hot carriers, resulting in improved device open circuit voltage （VOC）. As a result, the device PCE increases from 22.37%to 24.11%after the 4CPD treatment. In addition, the 4CPD-treated PSCs maintain 90%of the initial PCE after storage in an N2atmosphere at 50°C for 1,080 h, whereas the control devices show a 15%PCE loss under the same aging conditions. This work provides new opportunities to suppress interfacial charge recombination in inverted devices.

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Influence of introducing Zr,Ti,Nb and Ce elements on externally solidified crystals and mechanical properties of high-pressure die-casting Al–Si alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 147-153页

作者： Junjie Li Wenbo Yu Zhenyu Sun Weichen Zheng Liangwei Zhang Yanling Xue Wenning Liu Shoumei Xiong Center of Materials Science and Engineering School of Mechanical and Electronic Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Traffic&Transportation Engineering Central South UniversityChangsha 410075China Shanghai synchrotron radiation facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile *** can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated ***,the development of non-heat treatment Al alloys is becoming the hot *** addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of *** achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and *** influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic *** results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased ***,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical *** introduction of Ce resulted in the poisoning effect and reduced mechanical properties.

关键词： aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment

A new horizon for neuroscience:terahertz biotechnology in brain research

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Neural Regeneration Research 2025年第2期20卷 309-325页

作者： Zhengping Pu Yu Wu Zhongjie Zhu Hongwei Zhao Donghong Cui Shanghai Key Laboratory of Psychotic Disorders Shanghai Mental Health CenterShanghai Jiao Tong University School of MedicineShanghaiChina Department of Psychiatry Kangci Hospital of JiaxingTongxiangZhejiang ProvinceChina Shanghai synchrotron radiation facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghaiChina Key Laboratory of Interfacial Physics and Technology Shanghai Institute of Applied PhysicsChinese Academy of ScienceShanghaiChina National facility for Protein Science in Shanghai Shanghai Advanced Research InstituteChinese Academy of SciencesShanghaiChina

Terahertz biotechnology has been increasingly applied in various biomedical fields and has especially shown great potential for application in brain *** this article,we review the development of terahertz biotechnology and its applications in the field of *** evidence indicates promising prospects for the use of terahertz spectroscopy and terahertz imaging techniques in the diagnosis of amyloid disease,cerebrovascular disease,glioma,psychiatric disease,traumatic brain injury,and myelin *** vitro and animal experiments have also demonstrated the potential therapeutic value of terahertz technology in some neuropsychiatric *** the precise underlying mechanism of the interactions between terahertz electromagnetic waves and the biosystem is not yet fully understood,the research progress in this field shows great potential for biomedical noninvasive diagnostic and therapeutic ***,the biosafety of terahertz radiation requires further exploration regarding its two-sided efficacy in practical *** review demonstrates that terahertz biotechnology has the potential to be a promising method in the field of neuropsychiatry based on its unique advantages.

关键词： biological effect brain neuron neuropsychiatry neuroscience non-thermal effect terahertz imaging terahertz radiation terahertz spectroscopy terahertz technology

Mainchain conformation ordering self-assembly tailored room temperature phosphorescence emission

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Science China Chemistry 2025年第01期 329-336页

作者： Yuzhu Li Yumeng Gao Feng Tian Yu Wang Yuan Yao Shaoliang Lin Xiang Ma Binbin Xu Shanghai Key Laboratory of Advanced Polymeric Materials Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and Engineering East China University of Science and Technology Shanghai synchrotron radiation facility Shanghai Advanced Research Institute Chinese Academy of Sciences Key Laboratory for Advance Materials and Feringa Noble Prize Scientist Joint Research Centre Frontiers Science for Materiobiology and Dynamic Chemistry School of Chemistry and Molecular Engineering East China University of Science & Technology

Developing organic room-temperature phosphorescence （RTP） materials with a wide range of tunable-emission is significant in expanding the applications of RTP ***,we rationally designed amphiphilic alternating copolymers poly(1,2-bis（4-alkoxyphenyl）ethane-1,2-dione-alt-（ethylene glycol）x)(P（Bz-alt-EGx）) that combined the advantage of alternating benzil and EGxskeleton,and tunable mainchain *** a mainchain conformation ordering assembly （COA） process,P（Bz-alt-EGx） self-assembled into well-defined platelets,and such assemblies emitted blue RTP at ca.425 nm due to the ordered folded-chain conformation and confined *** contrast,traditional self-assembly （TA） of P（Bz-alt-EGx） obtained less ordered aggregates,such as asymmetric worms,vesicles,and rod-like *** resultant less ordered aggregates exhibited yellow-green RTP at ca.550 *** wide-tuning RTP emission in solution （between blue and yellow-green,over125 nm） is realized using the P（Bz-alt-EGx） alternating copolymers under the treatment of different self-assembly *** study uncovers a new strategy to tailor the RTP emission through different self-assembly pathways and holds great promise for the fabrication of advanced optical materials.

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Small angle X-ray scattering used in precipitation in AlZnMgCuLi alloy

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中国有色金属学会会刊：英文版 2003年第6期13卷 1301-1305页

作者：杜志伟周铁涛刘培英陈昌麒钟皓洪新国赵辉董宝中 School of Materials Science and Engineering Beijing synchrotron radiation facility Division

Small angle X-ray scattering has been used to study the variation of microstructure parameters in an Al-Zn-Mg-Cu-Li alloy aged at various temperatures for various durations. Coarsening of precipitates was studied by analyzing the curve of kinetics strength vs the cube of radius. The results show that the coarsening of precipitates conforms to LSW principle. In addition, the characteristic of s^3J(s) vs s curves was analyzed. The results show that the curves for samples aged at 160 ℃ for various durations(24, 48 and 96 h) have negative deviation, which maybe results in the formation of certain new precipitate. In the other aging treatment states, the curves conform to Porod principle which means there is sharp boundary between the precipitates and matrix.

关键词： AIZnMgCuLi合金铝合金析出 XRD 显微结构

Promoter of (Ce-Zr)O_2 Solid Solution Modified by Praseodymia in Three-Way Catalysts

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Journal of Rare Earths 2003年第4期21卷 430-435页

作者：汪文栋林培琰孟明伏义路胡天斗谢亚宁刘涛 Department of Chemical Physics Beijing synchrotron radiation facility

The three way catalysts (TWCs) promoters (Ce Zr)O 2, (Pr Ce Zr)O 2 and (Pr Zr)O 2 were prepared by sol gel like method. They were characterized by XRD, EXAFS and BET surface area determination. The reduction features of the promoters were measured by temperature programmed reduction (TPR) of H 2 to access the potential for the promoters containing praseodymia as oxygen storage component in three way catalyst. The (Pr Zr)O 2 cubic solid solution is formed at high temperature up to 800 ℃, which makes it more reducible than the (Ce Zr)O 2 solid solution. For the (Pr Ce Zr)O 2 samples, the ternary solid solution plays an important role in the reduction process. The performance of the three way catalysts with fully formulated Pt, Pd and Rh is proceeded by using both light off temperature under a stoichiometric gas composition and the conversion of CO, C 3H 6 and NO under changing air/fuel ratio at a constant reaction temperature 400 ℃ . The results indicate that a small amount of praseodymia doping into (Ce Zr)O 2 favors the light off temperature of C 3H 6 and NO, and all the catalysts containing praseodymia obviously exhibits enhanced width of S value for NO conversion at lean region ( S ≥1.00).

关键词： catalytic chemistry praseodymium (Ce Zr)O 2 solid solution three way catalysts rare earths

Quantitative evaluation of equatorial small-angle X-ray scattering for cylindrical fibers

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Chinese Physics B 2013年第4期22卷 354-359页

作者：李小芸李秀宏杨春明滑文强赵镍缪夏然田丰王玉柱边风刚王劼 Shanghai synchrotron radiation facility Shanghai Institute of Applied Physics Chinese Academy of Sciences

Elongated microvoids, internal fibrillar structure, and edge scattering from both surface refraction cause an equatorial streak in small angle X-ray scattering. A model for analyzing the edge scattering of fibers is proposed. Simulation results indicate that the intensity of edge scattering from surface refraction of a cylindrical fiber is strong and makes an important contribution to the equatorial streak. Two factors influence edge scattering intensity. One is the sample-to-detector distance （D）; edge scattering intensity increases with increasing D. The equatorial streak becomes weak when D is shortened. The other factor is the refraction index. Edge scattering intensity increases as the real component of the refraction index decreases. In experiment, weak or even no equatorial streaks were found for samples measured in a roughly index-matching fluid. Edge scattering can be eliminated or weakened, and it can be calculated by comparing the intensities of a cylindrical fiber when it is measured in air and in index-matching fluid. The simulation data are basically in agreement with the experimental data.

关键词： fiber edge scattering small angle scattering equatorial streak

The beam-based calibration of an X-ray pinhole camera at SSRF

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Chinese Physics C 2012年第1期36卷 80-83页

作者：冷用斌黄国庆张满洲陈之初陈杰叶恺容 Shanghai synchrotron radiation facility Shanghai Institute of Applied Physics

A pinhole camera for imaging X-ray synchrotron radiation from a dipole magnet is now in operation at the Shanghai synchrotron radiation facility （SSRF） storage *** electron beam size is derived by unfolding the radiation image and the point spread function （PSF） with deconvolution *** performance of the pinhole is determined by the accuracy of the PSF *** article will focus on a beam-based calibration scheme to measure the PSF system by varying the beam images with different quadrupole settings and fitting them with the corresponding theoretical beam *** this method at SSRF,the PSF value of the pinhole is revised from 37 to 44μ*** deviation in beam size between the theoretical value and the measured value isminimized to 4% after *** optimization allows us to observe the horizontal disturbance due to injection down to as small as 0.5μm.

关键词： beam diagnostics X-ray pinhole camera point spread function beam size measurement

Reconstructing a complex field from a series of its near-field diffraction patterns

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Chinese Physics B 2012年第10期21卷 260-264页

作者：洪友丽张凯王志立朱中柱赵雪娇黄万霞袁清习朱佩平吴自玉 Beijing synchrotron radiation facility Institute of High Energy PhysicsChinese Academy of Sciences National synchrotron radiation Laboratory University of Science and Technology of China

We propose a method for reconstructing a complex field from a series of its near-field diffraction *** method is based on the paraxial Fresnel diffraction equation without making further *** simulations are presented showing that a complex field can even be reconstructed with moderate qualities from its two near-field diffraction patterns and almost exact reconstructions can be obtained when three or more diffraction patterns are *** also show by numerical simulation that the correct diffraction distances can be recovered in case only coarsely measured values are *** method may be applied to phase imaging of weak-absorption objects.

关键词： phase imaging near field phase retrieval

Detection of Fe 3d electronic states in the valence band and magnetic properties of Fe-doped ZnO film

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Chinese Physics B 2013年第2期22卷 352-356页

作者：陈铁锌曹亮张旺韩玉岩郑志远徐法强奎热西钱海杰王嘉鸥 National synchrotron radiation Laboratory University of Science and Technology of China Beijing synchrotron radiation facility Institute of High Energy PhysicsChinese Academy of Sciences

Fe-doped ZnO film has been grown by laser molecular beam epitaxy（L-MBE） and structurally characterized by X-ray diffraction（XRD） and scanning electron microscopy（SEM）,all of which reveal the high quality of the *** secondary phase was *** photoemission spectroscopy（RPES） with photon energies around the Fe 2p-3d absorption edge is performed to detect the electronic structure in the valence band.A strong resonant effect at a photon energy of 710 eV is ***3＋ is the only valence state of Fe ions in the film and the Fe 3d electronic states are concentrated at binding energies of about 3.8 eV and 7 eV～8 *** are no electronic states related to Fe near the Fermi *** measurements reveal a typical superparamagnetic property at room *** absence of electronic states related to Fe near the Fermi level and the high quality of the film,with few defects,provide little support to ferromagnetism.

关键词： Fe-doped ZnO laser molecular beam epitaxy resonant photoemission spectroscopy superparamagnetism