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Journal of Rare Earths 2019年第10期37卷 1102-1107页

作者： Wenyun Yang Qiwei Hu Guanyi Qiao Liang Zha Shunquan Liu Jingzhi Han Honglin Du Yan Zhang Yingchang Yang Changsheng Wang State Key Laboratory for Mesoscopic PhySics School of PhysicsPeking UniversityBeijing100871China Beijing Key Laboratory for Magnetoeletric Materials and Devices Beijing100871China

In this work, we report the tuning effect of the Si substitution on the magnetic and high frequency electromagnetic properties of R2 Fe17 compounds and their paraffin compoSites. It is found that the introduction of Si can remarkably improve the magnetic and electromagnetic properties of the R2 Fe17 compounds, making the R2 Fe17 exSix-paraffin compoSites excellent microwave absorption materials(MAMs). By introducing the Si element, their saturation magnetizations decrease slightly, while much higher Curie temperatures are obtained. Furthermore, better impedance match is reached due to the decrease of the high-frequency permittivity ε’ by about 40%e50%, which finally enhances the performance of the microwave absorption. The peak frequency(fRL) of the reflection loss(RL) curve moves toward high frequency domain and the qualified bandwidth(QB, RL≤-10 dB) increases remarkably. The maximum QB of 3.3 GHz(12.0 e15.3 GHz) is obtained for the Sm1.5 Y0.5 Fe15 Si2-paraffin compoSite(d = 1.0 mm) and the maximum RL of -53.6 dB is achieved for Nd2 Fe15 Si2-paraffin compoSite(d = 2.2 mm), both surpasSing most of the reported MAMs. Additionally, a distinguished dielectric microwave absorption peak is observed, which further increases the QB in these compoSites.

关键词： Rare-earth tranSition-metal intermetallics Si substitution Magnetism CompoSites Microwave absorption properties

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Si/石墨复合负极材料的制备方法研究进展

化学学报 2017年第2期75卷 147-153页

作者：杜进林宁钱逸泰中国科学技术大学化学系

目前,锂离子电池被广泛地应用于移动电子设备、电动汽车以及混合动力汽车,因此,对高比容量以及长循环寿命的需求也愈加迫切.石墨类负极材料具有优异的循环性能,但理论比容量较低(372mA·h·g;),难以满足日益增长的高能量密度需求.Si负... 详细信息

目前,锂离子电池被广泛地应用于移动电子设备、电动汽车以及混合动力汽车,因此,对高比容量以及长循环寿命的需求也愈加迫切.石墨类负极材料具有优异的循环性能,但理论比容量较低(372mA·h·g;),难以满足日益增长的高能量密度需求.Si负极材料因具有较高的可逆比容量(3579mA·h·g;)而引起广泛关注.但是,巨大的体积膨胀限制了Si负极的使用.纳米化可以有效的释放Si体积膨胀带来的应力变化,提高其电化学性能.然而,单独的纳米材料具有很高的比表面会引起诸多副反应,阻碍其实际应用.将纳米Si与石墨复合制备Si/石墨复合材料,可充分利用纳米Si和石墨的优点,有望成为新一代高能量密度和长循环寿命锂离子电池负极材料.截至目前,多种技术手段被应用于制备纳米Si/石墨的复合材料,其核心问题是保证纳米Si和石墨的均匀分散以及稳定的结合.根据石墨与纳米Si的复合过程可以将该类材料的制备方法分为:固相法、液相法、以及气相沉积法.本综述对现有文献报道的Si/石墨复合材料制备方法以及所面临的主要问题进行简要总结概括.

关键词： Si 石墨复合方法负极材料锂离子电池

Si;N;粉粒度对振荡压力烧结Si;N;陶瓷的影响

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耐火材料 2022年

作者：徐广平何江荣刘鹏程茆忠军秦笑威谢志鹏江苏中磊节能科技发展有限公司清华大学材料学院

为了提高Si;N;陶瓷的烧结致密度，采用振荡压力烧结工艺分别在1 745和1 775 ℃制备了Si;N;陶瓷，主要研究了Si;N;粉的粒径（平均粒径分别为0.2、2.0、2.3 μm）对Si;N;陶瓷的显微结构和性能的影响。结果显示：1)在振荡压力烧结工艺下，... 详细信息

为了提高Si;N;陶瓷的烧结致密度，采用振荡压力烧结工艺分别在1 745和1 775 ℃制备了Si;N;陶瓷，主要研究了Si;N;粉的粒径（平均粒径分别为0.2、2.0、2.3 μm）对Si;N;陶瓷的显微结构和性能的影响。结果显示：1)在振荡压力烧结工艺下，由三种不同粒度的Si;N;粉制备的Si;N;陶瓷的相对密度都很大，为99.65%～99.86%，彼此相差很小。2)由平均粒径为0.2 μm的Si;N;粉在1 745 ℃烧结制备的试样的微观结构最均匀，其β- Si;N;晶粒平均长径比、抗弯强度和维氏硬度均最大，分别达到5.0、1 364 MPa±65 MPa和15.72 GPa±0.8 GPa；由平均粒径为2.3 μm的Si;N;粉在1 745 ℃烧结制备的试样的β- Si;N;晶粒平均长径比、抗弯强度和维氏硬度均最小，分别为3.3、846 MPa±49 MPa和13.82 GPa±0.8 GPa。

关键词： Si N 陶瓷振荡压力烧结相对密度长径比抗弯强度维氏硬度

Optical saturation characteristics of dual-and Single-injection Ge-on-Si photodetectors

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Chinese Optics Letters 2018年第7期16卷 78-81页

作者：崔积适白博文杨丰赫周治平 State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer Science Peking University

The optical saturation characteristics in the germanium-on-Silicon（Ge-on-Si） photodetector are studied for the first time, to the best of our knowledge. The relationship between the optical saturation characteristics and the optical field distribution in the Ge layer is illustrated by the Simulation. This theory is verified by comparative experiments with Single-injection and dual-injection structures. The dual-injection photodetector with a more balanced and uniform optical field distribution has a 13% higher responSivity at low optical power and 74.4%higher saturation current at 1550 nm. At higher optical power, the bandwidth of the dual-injection photodetector is five times larger than that of the Single-injection photodetector.

关键词： Ge Optical saturation characteristics of dual-and Single-injection Ge-on-Si photodetectors Si

Hierarchically 3D structured milled lamellar MoS2/nano-Silicon@carbon hybrid with medium capacity and long cycling sustainability as anodes for lithium-ion batteries

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Journal of Materials Science & Technology 2019年第9期35卷 1840-1850页

作者： Peng Zhang Qiang Rua Honglin Yan Xianhua Hou Fuming Chen Shejun Hu Lingzhi Zhao Guangdong Engineering Technology Research Center o f Efficient Green Energy and Environmental Protection Materials South China Normal University Guangzhou 510006China Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials School of Physics and Telecommunication EngineeringSouth China Normal UniversityGuangzhou 510006China Engineering Research Center of Materials and Technology for Electrochemical Energy Storage (Ministry of Education) Guangzhou 510006China Institute of Optoelectronic Materials and Technology South China Normal UniversityGuangzhou 510631China

A hierarchically 3D structured milled lamellar MoS2/nano-SiIicon@carbon hybrid with medium capacity and long-term lifespan is deSigned by a green and scalable approach uSing ball milling process and spraydrying/ pyrolySis routes. The microspheres conSist of low-content nano-Silicon (20 wt%), milled lamellar M0S2 sheets and porous carbon skeletons. A mixture of Silicon nanoparticles and M0S2 flakes serves as an inner core, while porous carbon pyrolyzed from petroleum pitch acts as a protective shell. The particular architecture affords robust mechanical support, abundant buffering space and enhanced electrical conductivity, thus effectively accommodating drastic volume variation during repetitive Li+ intercalation/ extraction. The Si/MoS2@C hybrid delivers a high initial discharge specific capacity of 1257.8 mA hg^-1 and exhibits a reverSible capacity of 767.52 m A hg^-1 at a current denSity 100 mA g'1 after 250 cycles. Most impresSively, the electrode depicts a superior long-cycling durability with a discharge capacity of 537.6 mA hg^-1 even after 1200 cycles at a current denSity of 500 m A g^-1. Meanwhile, the hybrid also shows excellent rate performance such as 388.1 mA h g^-1 even at a large current denSity of 3000 mA g^-1.

关键词： Si MoS2 Medium capacity Long-term lifespan Lithium ion batteries

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SiN多孔陶瓷制备技术研究进展

陶瓷学报 2023年 607-622+2页

作者：谢骏豪张笑妍干科中国科学院过程工程研究所中国科学院绿色过程与工程重点实验室北京工业大学材料与制造学部北京科技大学新材料技术研究院

Si3N4多孔陶瓷具有轻质高强、高比表面积、低热导率及介电常数等优势，是高温结构部件、吸附过滤、催化剂载体、透波材料、生物支架等最佳候选材料。Si3N4多孔陶瓷的制备技术直接决定其微观结构及综合性能。从原料体系出发，概述了Si3N... 详细信息

Si3N4多孔陶瓷具有轻质高强、高比表面积、低热导率及介电常数等优势，是高温结构部件、吸附过滤、催化剂载体、透波材料、生物支架等最佳候选材料。Si3N4多孔陶瓷的制备技术直接决定其微观结构及综合性能。从原料体系出发，概述了Si3N4多孔陶瓷的制备思路，进一步对常规的Si3N4多孔陶瓷制备工艺的基本情况进行分析，将为Si3N4多孔陶瓷微观结构的设计及综合性能调控提供参考。

关键词： Si N 多孔陶瓷微观结构力学性能

Heavy ion micro-beam study of Single-event tranSient(SET) in Si Ge heterjunction bipolar tranSistor

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Science China(Information Sciences) 2017年第12期60卷 120-122页

作者： Jinxin ZHANG Hongxia GUO Fengqi ZHANG Chaohui HE Pei LI Yunyi YAN Hui WANG Linxia ZHANG School of Aerospace Science and Technology Xidian University Xinjiang Technical Institute of PhySics & Chemistry Chinese Academy of Sciences Northwest Institution of Nuclear Technology School of Energy and Power Engineering Xi'an Jiaotong University

Silicon-germainum heterojunction bipolar tranSistor(Si Ge HBT)has been demonstrated to be suitable in extreme environment because of its superior temperature characteristics which can operate from 43 K to 400 K[1].In addition,outstanding hardness to both total ionizing dose(TID)radiation and displacement damage make Si Ge HBT technology particularly attractive for space

关键词： Si Heavy ion micro-beam study of Single-event tranSient Ge HBT SET

Anti-Reflection Characteristics of Si Nanowires for Enhanced Photoluminescence from CdTe/CdS Quantum Dots

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Chinese PhySics Letters 2018年第5期35卷 91-94页

作者：王红玉单丹徐岭 Tongda College Nanjing University of Posts and Telecommunications National Laboratory of Solid State Microstructure and School of Electronic Science and Engineering Nanjing University School of Electronic and Information Engineering Yangzhou Polytechnic Institute

CdTe/CdS quantum dots（QDs） are fabricated on Si nanowires（NWs） substrates with and without Au nanoparticles（NPs）. The formation of Au NPs on Si NWs can be certified as shown in scanning electron microscopy images. The optical properties of samples are also investigated. It is interesting to find that the photoluminescence（PL） intenSity of Cd Te/Cd S QD films on Si nanowire substrates with Au NPs is Significantly increased,which can reach 8-fold higher than that of samples on planar Si without Au NPs. The results of finite-difference time-domain Simulation indicate that Au NPs induce stronger localization of electric field and then boost the PL intenSity of QDs nearby. Furthermore, the time-resolved luminescence decay curve shows the PL lifetime, which is about 5.5 ns at the emisSion peaks of QD films on planar, increaSing from 1.8 ns of QD films on Si NWs to4.7 ns after introducing Au NPs into Si NWs.

关键词： Si QDs Anti-Reflection Characteristics of Si Nanowires for Enhanced Photoluminescence from CdTe/CdS Quantum Dots CdS

Si对K325铸造高温合金的凝固行为和拉伸性能的影响

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中国有色金属学报 2017年第10期27卷 2029-2036页

作者：肖旋刘庆丰王常帅周兰章沈阳理工大学材料科学与工程学院沈阳110159 中国科学院金属研究所沈阳110016

采用扫描电镜、电子探针和差热分析等方法研究Si含量对铸造高温合金K325凝固行为、组织特征和拉伸性能的影响。结果表明:Si添加粗化枝晶、加重Nb元素偏析且偏析程度随Si含量增加呈增大趋势。不含Si合金的凝固路径为L→L+γ→L+γ+MC→γ... 详细信息

采用扫描电镜、电子探针和差热分析等方法研究Si含量对铸造高温合金K325凝固行为、组织特征和拉伸性能的影响。结果表明:Si添加粗化枝晶、加重Nb元素偏析且偏析程度随Si含量增加呈增大趋势。不含Si合金的凝固路径为L→L+γ→L+γ+MC→γ+MC,铸态相组成为γ+MC。含Si合金的凝固路径为L→L+γ→L+γ+MC→L+γ+MC+γ/Laves→γ+MC+γ/Laves,铸态相组成为γ+MC+γ/Laves。此外,随着Si含量的升高,γ/Laves共晶相的尺寸明显增大且量明显增加,形貌由半连续状向连续致密筛网状和花瓣状转变。固溶处理后含Si合金中的γ/Laves共晶消失,相组成为γ+MC+Laves相,Laves相为具有尖锐棱角的块状。随Si含量增加,块状Laves相含量明显增多,Si含量为1.5%(质量分数)时,形成Laves相团簇区。Si对拉伸强度的影响与Si含量密切相关,小于1.0%的Si对合金抗拉强度无明显影响,然而Si含量为1.5%,抗拉强度明显降低。

关键词： Si 铸造K325合金凝固特性组织特征拉伸性能

金刚石/Al(或AlSi合金)复合材料性能衰退及抑制

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复合材料学报 2019年第3期36卷 669-676页

作者：陆晨君徐俊裴喜伟潘徐杰陈锋东南大学材料科学与工程学院江苏省先进金属材料高技术研究重点实验室南京211189 江苏神通阀门股份有限公司启东226232

采用气体压力浸渗法制备了金刚石/Al、金刚石/AlSi7和金刚石/AlSi9复合材料,对比研究了其暴露在空气中的性能衰退行为。研究表明,界面反应产物Al_4C_3会潮解生成Al(OH)3,增大界面热阻,导致金刚石/Al复合材料性能衰退。Al基体中添加Si元... 详细信息

采用气体压力浸渗法制备了金刚石/Al、金刚石/AlSi7和金刚石/AlSi9复合材料,对比研究了其暴露在空气中的性能衰退行为。研究表明,界面反应产物Al_4C_3会潮解生成Al(OH)3,增大界面热阻,导致金刚石/Al复合材料性能衰退。Al基体中添加Si元素可以显著降低其性能衰退速率,其机制为:金刚石中C元素在Al液中溶解度的降低和Si在金刚石颗粒表面的优先析出,抑制了Al_4C_3的生成量;此外,金刚石/AlSi复合材料致密度的提高,对Al_4C_3与水汽的接触起到阻碍作用。讨论了抑制金刚石/Al复合材料性能衰退的几种可行方法,有望进一步提高其在潮湿环境中的使用寿命。

关键词：金刚石/Al 复合材料 Al4C3 Si 热导率衰退