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Charge-balanced codoping enables exceeding doping limit and ultralow thermal conductivity

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中国科学技术大学学报 2024年第6期54卷 1-7,I0009页

作者： Long Chen Chun Wang Lin Wang Minghao Wang Yongchun Zhu Changzheng Wu School of Chemistry and Materials Science University of Science and Technology of ChinaHefei 230026China hefei national Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China Institute of Energy Hefei Comprehensive National Science CenterHefei 230031China

Materials with low thermal conductivity are applied extensively in energy management,and breaking the amorphous limits of thermal conductivity to solids has attracted widespread attention from *** is a common strategy for achieving low thermal conductivity that can offer abundant scattering centers in which heavier dopants always result in lower phonon group velocities and lower thermal ***,the amount of equivalent heavyatom single dopant available is ***,nonequivalent heavy dopants have finite solubility because of charge ***,we propose a charge balance strategy for SnS by substituting Sn2+with Ag^(+)and heavy Bi^(3+),improving the doping limit of Ag from 2%to 3%.Ag and Bi codoping increases the point defect concentration and introduces abundant boundaries simultaneously,scattering the phonons at both the atomic scale and *** thermal conductivity of Ag0.03Bi0.03Sn0.94S decreased to 0.535 W·m^(−1)·K^(−1)at room temperature and 0.388 W·m^(−1)·K^(−1)at 275°C,which is below the amorphous limit of 0.450 W·m^(−1)·K^(−1)for *** strategy offers a simple way to enhance the doping limit and achieve ultralow thermal conductivity in solids below the amorphous limit without precise structural modification.

关键词： charge-balanced codoping heavy atom point defect grain boundary ultralow thermal conductivity

Linear magnetoresistance and structural distortion in layered SrCu_(4-x)P_(2) single crystals

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Chinese Physics B 2024年第1期33卷 591-594页

作者：聂勇陈正韦文森李慧杰张勇梅明王园园宋文海宋东升王钊胜朱相德宁伟田明亮 Anhui Key laboratory of Low-energy Quantum Materials and Devices High Magnetic Field LaboratoryHFIPSChinese Academy of SciencesHefei 230031China Department of Physics University of Science and Technology of ChinaHefei 230026China Key laboratory of Materials Physics Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China Information Materials and Intelligent Sensing laboratory of Anhui Province Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationInstitutes of Physical Science and Information TechnologyAnhui UniversityHefei 230601China School of Physics Anhui UniversityHefei 230601China

We report a systematic study on layered metal SrCu_(4-x)P_(2) single crystals via transport, magnetization, thermodynamic measurements and structural characterization. We find that the crystals show large linear magnetoresistance without any sign of saturation with a magnetic field up to 30T. We also observe a phase transition with significant anomalies in resistivity and heat capacity at T_(p)~140 K. Thermal expansion measurement reveals a subtle lattice parameter variation near Tp, i.e.,?L_(c)/L_(c)~0.062%. The structural characterization confines that there is no structure transition below and above T_(p). All these results suggest that the nonmagnetic transition of SrCu_(4-x)P_(2) could be associated with structural distortion.

关键词： linear magnetoresistance thermal expansion specific heat structural distortion

高性能锂离子电池用N掺杂C-Sn交联纳米纤维自支撑电极的理性设计（英文）

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物理化学学报 2024年第3期 39-49页

作者：李莹赵钰燊陈凯刘旭伊廷锋陈立锋东北大学材料科学与工程学院东北大学秦皇岛分校资源与材料学院河北省电介质与电解质功能材料重点实验室中国科学院材料力学行为与设计重点实验室中国科学技术大学工程科学学院热科学和能源工程系

为了提高碳材料作为锂离子电池负极材料的比容量，将氮掺杂的碳纤维与高容量的Sn进行复合。通过静电纺丝及低温碳化制备了均匀镶嵌Sn纳米颗粒的氮掺杂碳纳米纤维(C-Sn)复合膜。该复合膜直接用作自支撑锂离子电池负极时表现出较好的电化... 详细信息

为了提高碳材料作为锂离子电池负极材料的比容量，将氮掺杂的碳纤维与高容量的Sn进行复合。通过静电纺丝及低温碳化制备了均匀镶嵌Sn纳米颗粒的氮掺杂碳纳米纤维(C-Sn)复合膜。该复合膜直接用作自支撑锂离子电池负极时表现出较好的电化学性能，Sn的引入显著提高了碳纳米纤维膜的电化学性能。碳均匀包覆Sn后形成的纤维结构可以促进离子电子的传导，并能有效缓冲Sn纳米粒子在循环过程中的体积变化，从而有效抑制粉化与团聚。Sn含量约为25.6%的CSn-2电极具有最高的比容量和更优异的倍率性能。电化学测试结果表明，在2A·g-1的电流密度下，充放电循环1000圈后充电(放电)比容量为412.7(413.5)mAh·g-1。密度泛函理论(DFT)计算结果表明，N掺杂非晶碳与锂具有良好的亲和性，有利于将合金化反应之后形成的SnxLiy合金锚定在碳表面，进而缓解了充放电过程中的Sn的体积变化。本文为高性能储锂材料的设计提供了一种切实可行的策略。

关键词：自支撑电极碳纤维金属锡锂离子电池循环稳定性

Polyoxovanadate ionic crystals with open tunnels stabilized by macrocations for lithium-ion storage

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Nano Research 2023年第7期16卷 9267-9272页

作者： Jie Wang Lin Wang Congyan Liu Yan Wang Fei Ye Wen Yan Bo Liu School of Chemistry and Materials Science University of Science and Technology of ChinaHefei 230026China

Polyoxometalates(POMs)with multiple redox active sites have been reported as charge sponge for lithium-ion batteries(LIBs).Herein,we for the first time introduce a polyoxovanadate(POV)ionic crystals with macrocations,[Ni(Phen)_(3)][ClV_(14)O_(34)]Cl(NiV_(14),Phen=1,10-phenanthroline),as an anode material for *** existence of macrocation[Ni(Phen)_(3)]^(2+)stabilizes the open tunnels inside NiV_(14).The NiV_(14)electrode exhibits superior rate capabilities(1083 mAh·g^(-1)at 100 mA·g^(-1)and 384 mAh·g^(-1)at 2000 mA·g^(-1))due to the rapid capacitive dominated contribution and high Li^(+)ions diffusion coefficients(3.3×10^(-12) cm^(-2)·s^(-1)),and it delivers a remarkable cycling stability with a Coulombic efficiency of 99.7%after 1000 cycles at 2000 mA·g^(-1).Such performance can be attributed to the stable structure of NiV14 and the highly reversible valence changes of vanadium during the charge/discharge processes,which are revealed by a combination of in situ X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),and X-ray absorption fine structure(XAFS)*** work not only demonstrates that NiV_(14) with open tunnels stabilized by macrocation is a promising anode material for high performance LIBs,but also provides important references for the rational design of POMs electrode materials in advanced energy storage systems.

关键词： polyoxometalates(POMs) ionic crystals lithium-ion battery(LIB) macrocation energy storage mechanism

Bulky nanodiamond-confined synthesis of sub-5 nanometer ordered intermetallic Pd_(3)Pb catalysts

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Nano Research 2022年第6期15卷 4973-4979页

作者： Lei Wang Peng Yin Wei-Jie Zeng Shi-Long Xu Ping Chen Hai-Wei Liang Department of Chemistry University of Science and Technology of ChinaHefei 230026China School of Chemistry and Chemical Engineering Anhui UniversityHefei 230601China

Modulation of geometric and electronic structures of supported Pd-based catalysts by forming atomically ordered intermetallic phases enables an effective way to optimize catalytic ***,the synthesis of small-sized Pd-based intermetallic nanoparticle catalysts with improved mass-based activity remains formidable challenges,since high-temperature annealing generally required for atom ordering inevitably leads to severe metal sintering and thus large ***,we present a bulky nanodiamond-confined method to prepare sub-5 nm Pd_(3)Pb intermetallic nanocatalysts by mitigating metal sintering at high temperatures,which is induced by the electronic interactions between metal and defect-rich graphene shells reinforced by diamond cores in the bulky nanodiamond *** prepared small-sized Pd_(3)Pb intermetallic catalyst displays a high activity with a turnover frequency of 932 h−1 for the semihydrogenation of phenylacetylene under mild conditions(room temperature,3 bar H_(2)),along with a high selectivity of>96%to styrene near the complete conversion of phenylacetylene.

关键词： Pd_(3)Pb intermetallic compound bulky nanodiamond strong metal-support interaction alkynes semihydrogenation

HMGB3 is a potential diagnostic marker for early cervical lesion screening

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Genes & Diseases 2023年第6期10卷 2202-2205页

作者： Qianwen Cui Jiarong Zhao Qingmei Deng Yu Liu Changfang Fu Qiang Wu Qiuyan Sun Haiyan Weng Haiming Dai Wulin Yang Anhui Province Key laboratory of Medical Physics and Technology Institute of Health and Medical TechnologyHefei Institutes of Physical ScienceChinese Academy of SciencesHefeiAnhui 230031China Science Island Branch Graduate School of University of Science and Technology of ChinaHefeiAnhui 230026China Medical Pathology Center Hefei Cancer HospitalChinese Academy of SciencesHefeiAnhui 230031China The First Affiliated Hospital of USTC Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui 230001China Department of Pathology The First Affiliated Hospital of Anhui Medical UniversityHefeiAnhui 230601China

Despite the spread of effective vaccination strategies,cervical cancer remains the second leading cause of cancer death among women aged 20 to 39.1 clinical diagnosis of cervical lesions relies on the P16INK4a(P16)marker,but its sensitivity to low-grade cervical intraepithelial neoplasia(CIN)is *** more sensitive and specific molecular markers is still a challenge in cervical lesion *** this study,we found that HMGB3 could effectively label pathological cells in different cervical lesions,especially for early ***,HMGB3 has the potential to be used as a novel marker for the early screening of cervical lesions.

关键词： cervical diagnosis clinical

Dark-field line confocal imaging with point confocality and extended line field for bulk defects detection

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Chinese Optics Letters 2023年第4期21卷 26-30页

作者：董敬涛张腾达杨蕾张育中卢荣胜谢兴龙 Anhui Province Key laboratory of Measuring Theory and Precision Instrument School of Instrument Science and Opto-electronic EngineeringHefei University of TechnologyHefei 230009China Key laboratory of High Power Laser and Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China

Fabrication of high-quality optics puts a strong demand on high-throughput detection of macroscopic bulk defects in optical components.A dark-field line confocal imaging method is proposed with two distinct advantages:(ⅰ)a point-to-line confocal scheme formed by a columnar elliptical mirror and an optical fiber bundle breaks through the constraint on light collection angle and field of view in the traditional line confocal microscopy using an objective,allowing for an extended confocal line field of more than 100 mm while maintaining a light collection angle of 27°;(ⅱ)the bulk defects are independently illuminated as a function of time to eliminate the cross talk in the direction of the confocal slit,thus preserving point confocality and showing the optical section thicknesses to be 162μm in the axial direction,and 19 and 22μm in the orthogonal transverse *** experimental results verify that the method has a minimum detectable bulk defect of less than 5μm and an imaging efficiency of 400 mm2/*** method shows great potential in high-throughput and highsensitivity bulk defects detection.

关键词： line confocal imaging dark-field imaging bulk defects detection

Thermoelectric properties of (GeTe)_(1-x)[(Ag_(2)Te)_(0.4)(Sb_(2)Te_(3))_(0.6)]_(x) alloys

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Rare Metals 2022年第3期41卷 921-930页

作者： Hong-Xia Liu Xin-Yue Zhang Zhong-Lin Bu Wen Li Yan-Zhong Pei School of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China laboratory of Magnetic and Electric Functional Materials and the Applications The Key Laboratory of Shanxi ProvinceTaiyuan 030024China Interdisciplinary Materials Research Center School of Materials Science and EngineeringTongji UniversityShanghai 201804China

The(GeTe)_(x)(AgSbTe_(2))_(100-x)alloys(TAGS-x)have been demonstrated as a promising p-type candidate for thermoelectric applications,attracting numerous atten-tions on the advancements of thermoelectric *** of carrier concentration for optimizing ther-moelectric performance in TAGS can be achieved by varying the ratio of Ag to Sb,and the Ag/Sb ratio of~2/3 has been proven as the optimal ***,this work focuses on the systematic investigation on ther-moelectric properties of(GeTe)_(1-x)[(Ag_(2)Te)_(0.4)(Sb_(2)Te_(3))_(0.6)]_(x) *** crystal structure for the alloys transfers from rhombohedral to cubic at room temperature as x≥*** evolution of band parameter is estimated using a single parabolic band(SPB)model with acoustic phonon *** density of states effective mass increases with x increasing,which leads to an enhancement of Seebeck coefficient along with a reduction in Hall mobility due to the additional carrier scattering by point ***-while,the lattice thermal conductivity of lower than~0.7 W·m^(-1)·K^(-1) in the entire temperature range and the lowest one of only 0.45 W·m^(-1)·K^(-1) is achieved due to additional phonon scattering by point *** a result,a peak thermoelectric figure of merit(zT)of~1.80 and an average one of~1.37 in 300–800 K are realized in non-stoichiometric TAGS alloys here.

关键词： Thermoelectric Tellurium-antimonygermanium-silver(TAGS) Crystal structure Lattice thermal conductivity

Intermetallic IrGa-IrO_(x) core-shell electrocatalysts for oxygen evolution Hide Author's Information

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Nano Research 2022年第3期15卷 1853-1860页

作者： Lin-Wei Chen Fuxiang He Ru-Yang Shao Qiang-Qiang Yan Peng Yin Wei-Jie Zeng Ming Zuo Lixin He Hai-Wei Liang Division of Nanomaterials&Chemistry Hefei National Laboratory for Physical Sciences at the MicroscaleDepartment of ChemistryUniversity of Science and Technology of ChinaHefei 230026China School of Pharmacy Anhui University of Chinese MedicineHefei 230012China Key laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China. Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China

The development of high-performance Ir-based catalyst for electrocatalysis of oxygen evolution reaction(OER)in acidic media plays a critical role in realizing the commercialization of polymer electrolyte membrane-based water electrolyzer *** we report a low-Ir core–shell OER electrocatalyst consisting of an intermetallic IrGa(IrGa-IMC)core and a partially oxidized Ir(IrOx)*** acidic electrolytes,the IrGa-IMC@IrOx core–shell catalysts exhibit a low overpotential of 272 mV at 10 mA·cm^(−2) with Ir loading of~20µg·cm^(−2) and a mass activity of 841 A·gIr^(−1) at 1.52 V,which is 3.6 times greater than that of commercial Ir/C(232 A·gIr^(−1))*** understand by the density functional theory(DFT)calculations that the enhanced OER activity of the IrGa-IMC@IrO_(x) catalysts is ascribed to the lifted degeneracy of Ir 5d electron of surface IrO_(x) sites induced by the intermetallic IrGa core,which increases the adsorption capacity of IrO_(x) layer for O and OH binding and eventually lowers the energy barrier of the OER rate-determining steps.

关键词： IrGa intermetallics electrocatalysts oxygen evolution reaction core−shell