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CeN薄膜表面Cr和Ti抗氧化涂层的制备与性能研究

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真空科学与技术学报 2024年第6期44卷 529-536页

作者：罗凯肖易蒋琬玉贾永峰蒋玉苹曹林洪符亚军西南科技大学材料与化学学院绵阳621000

采用直流磁控溅射在单晶硅基底上制备了2μm厚的氮化铈(CeN)薄膜,并研究了CeN在大气环境中的氧化行为。鉴于CeN在大气环境中容易与氧气反应而劣化分解这一问题,在CeN上沉积了不同厚度的钛(Ti)或铬(Cr)抗氧化涂层以提高其抗氧化性能。实... 详细信息

采用直流磁控溅射在单晶硅基底上制备了2μm厚的氮化铈(CeN)薄膜,并研究了CeN在大气环境中的氧化行为。鉴于CeN在大气环境中容易与氧气反应而劣化分解这一问题,在CeN上沉积了不同厚度的钛(Ti)或铬(Cr)抗氧化涂层以提高其抗氧化性能。实验结果表明,Ti/CeN复合薄膜在大气环境中暴露较短时间内就会起皮脱落;2.4μm Cr/2μm CeN复合薄膜可以有效地延长CeN在大气环境中的存放时间。最后,探讨了CeN与抗氧化层复合薄膜的氧化机理。

关键词：磁控溅射氮化铈抗氧化涂层

Thermally assisted switching in FePt single-domain particles with a Gaussian distribution of temperature

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Science China(Physics,Mechanics & Astronomy) 2011年第7期54卷 1263-1266页

作者： TANG Ke YANG HongJie cao linhong YU HongTao LIU JinSong WANG JunXia School of Electronics and Electrical Engineering Chongqing University of Arts and Sciences Yongchuan 402160 China State Key Laboratory Cultivation Base for Nonmetal Composite and Functional Materials Southwest University of Science and Technology Mianyang 621010 China

Magnetic nanoscale systems,including nanodots,nanofibers,nanowires and nanoparticles,are currently attracting great interest due to their interesting physical and promising applications in various fields,such as magnetic recording,sensors,target drugs and catalysts,as well as *** achieve ultrahigh recording density,the method of heat assisted magnetic recording(HAMR) has been *** this work,with the help of a Monte Carlo method,the mechanisms of thermally assisted magnetization switching in FePt single-domain particles driven by an external magnetic field are investigated,where the temperature in the particles is assumed to follow a Gaussian *** nucleation modes are observed for different distributions of *** is initiated by many droplets,which join each other at the boundary of the system;the other is ini-tiated by many droplets at the boundary,but in growth tending toward the inner part of the *** inverse proportional relationship between the metastable lifetime and the distribution is also found.

关键词： magnetization switching Monte Carlo simulation nucleation Gaussian distribution

The Nucleation Process in the Preparation of Graphene Films by Pulsed Laser Deposition

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Journal of Wuhan University of Technology(Materials Science) 2018年第2期33卷 343-348页

作者：王进 WANG Xuemin YU Jian XIAO Tingting PENG Liping XIONG Zhengwei cao linhong WANG Chuanbin 沈强 State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Research Center of Laser Fusion China Academy of Engineering Physics Laboratory for Extreme Conditions Matter Properties Southwest University of Science and Technology School of Materials Science and Engineering Southwest University of Science and Technology

The nucleation process of graphene films prepared by pulsed laser deposition has been investigated in detail. It is found that graphene nucleates at the steps on the substrate surface firstly, from aggregation of nuclei into particles. High pulsed laser energy offers large incident energy for carbon particles deposited on the surface of the substrate, which is beneficial to the nucleation of graphene. A lot of steps are formed on the copper substrate due to the high temperature, so that the high incident energetic carbon species are able to form a stable nucleus at the steps. As the incident particles increases, the graphene nuclei are combined to grow together. Further, it is found that graphene tends to form few layer graphene particles instead of large graphene sheets.

关键词： graphene PLD nucleation

Heterogeneous Growth of ZnO Crystal on GaN/Al_(2)O_(3) Substrate

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Journal of Wuhan University of Technology(Materials Science) 2022年第4期37卷 576-579页

作者： FAN Long ZHONG Changjie WANG Xuemin cao linhong WANG Jin PENG Liping ZHAN Zhiqiang XIONG Zhengwei WU Weidong Laser Fusion Research Center China Academy of Engineering PhysicsMianyang 621900China Southwest University of Science and Technology Mianyang 621010China

Hydrothermal(HT)ZnO substrates were usually used as seeds for the vapor growth of ZnO *** this work,ZnO bulk crystals were grown using the relatively low-cost GaN/AlOsubstrates as seeds by chemical vapor transport(CVT).With the increase of growth time,the dislocation densities in the crystal decreased from about 1×10^(6) to 6×10^(3) cm^(-2).The carrier concentration decreased from 1.24×10^(19) to 1.57×10^(17)cm^(-3),while the carrier mobility increased from 63.8 to 179 cm^(2)/(V·s).The optical transmittance in the VIS-NIR wavelength increased significantly in combination with the decreasing dislocation densities and impurity *** dislocation lines and related fast diffusion paths gradually decreased and disappeared in the late growth stage,and the crystal qualities were consequently *** experimental results show that the properties of as-grown ZnO crystals are comparable with bulk ZnO grown on the HT substrates to some *** GaN/Al_(2)O_(3) seeds may have a potential application value in the industrial production of ZnO single crystals.

关键词： ZnO single crystal GaN/Al_(2)O_(3)substrates chemical vapor transport heterogeneous growth

Manipulating metal-insulator transitions of VO_(2) films via embedding Ag nanonet arrays

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Chinese Physics B 2021年第12期30卷 539-543页

作者： Zhangyang Zhou Jia Yang Yi Liu Zhipeng Gao linhong cao Leiming Fang Hongliang He Zhengwei Xiong Institute of Fluid Physics China Academy of Engineering PhysicsMianyang 621900China Joint Laboratory for Extreme Conditions Matter Properties Southwest University of Science and TechnologyMianyang 621010China Institute of Physics Nuclearand ChemistryChina Academy of Engineering PhysicsMianyang 621900China School of Materials Science and Engineering Southwest University of Science and TechnologyMianyang 621010China

Manipulating metal-insulator transitions in strongly correlated materials is of great importance in condensed matter physics,with implications for both fundamental science and *** dioxide(VO_(2)),as an ideal model system,is metallic at high temperatures and shown a typical metal-insulator structural phase transition at 341 K from rutile structure to monoclinic *** behavior has been absorbed tons of attention for ***,how to control this phase transition is still challenging and little *** we demonstrated that to control the Ag nanonet arrays(NAs)in monoclinic VO_(2)(M)could be effective to adjust this metal-insulator *** the increase of Ag NAs volume fraction by reducing the template spheres size,the transition temperature(Tc)decreased from 68°C to 51°*** mechanism of Tc decrease was revealed as:the carrier density increases through the increase of Ag NAs volume fraction,and more free electrons injected into the VO_(2)films induced greater absorption energy at the internal nanometal-semiconductor *** results supply a new strategy to control the metal-insulator transitions in VO_(2),which must be instructive for the other strongly correlated materials and important for applications.

关键词： vanadium dioxide volume fraction Ag nanonet arrays metal-insulator transition

Investigation of High Catalyteal Durability for Porous Pt Films Deposited via Magnetron Sputtering

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Journal of Wuhan University of Technology(Materials Science) 2022年第2期37卷 194-201页

作者： LIU Guangquan PENG Liping FAN Long WANG Jin FU Yajun XIONG Zhengwei REN Xuetan cao linhong WU Weidong School of Materials Science and Engineering Southwest University of Science and TechnologyMianyang 621010China Science and Technology on Plasma Physics Laboratory Research Center of LaserFusionChina Academy of Engineering PhysicsMianyang 621900China Collaborative Innovation Center of IFSA(CICIFSA) Shanghai Jiao Tong University Shanghai 200240China

Porous Pt thin films were prepared on carbon papers by a single-step ultra-high dc magnetron sputtering method to obtain ideal electrodes for proton exchange membrane fuel *** platinum loading of the electrocatalyst layer is controlled at about 0.1 mg·cm^(-2).Structural characteristics and catalytic activities of the films were analyzed by scanning electron microscopy,atomic force microscopy,X-ray diffraction,cyclic voltammetry,and stress durability testing *** effect of treatment conditions of a substrate on the structural and performance characteristics of the catalytic films was shown as *** produced on acid-treated carbon papers at the argon pressure of 0.01 mbar possessed a homogeneous,highly developed surface along with a porous *** to Pt/TCPW(Toray carbon papers soaked in ultrapure water)electrodes,the film obtained on the acid-treated substrate had a larger electrochemical surface area(163.33 m^(2)·g^(-1))and exhibited better catalytic stability and durability due to a porous structure as a result of Pt particle accumulation.

关键词： dc magnetron sputtering catalytic films catalytic stability durability

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锂盐助烧铌镁酸铅-钛酸铅陶瓷的压电性能

硅酸盐学报 2008年第6期36卷 756-759,764页

作者：曹林洪姚熹徐卓西南科技大学材料科学与工程学院四川绵阳621010 西安交通大学电子材料研究所西安710049

采用铌铁矿预产物合成法制备了锂盐[碳酸锂(Li2CO3),硝酸锂(LiNO3),氟化锂(LiF)]助烧0.68Pb(Mg1/3Nb2/3)O3–0.32 PbTiO3(PMN–PT68/32)弛豫铁电陶瓷。用X射线衍射分析陶瓷相组成并测试PMN–PT68/32的压电性能。结果表明:所有陶瓷样品... 详细信息

采用铌铁矿预产物合成法制备了锂盐[碳酸锂(Li2CO3),硝酸锂(LiNO3),氟化锂(LiF)]助烧0.68Pb(Mg1/3Nb2/3)O3–0.32 PbTiO3(PMN–PT68/32)弛豫铁电陶瓷。用X射线衍射分析陶瓷相组成并测试PMN–PT68/32的压电性能。结果表明:所有陶瓷样品均为纯钙钛矿相,无任何其它杂相。添加Li2CO3和LiNO3可以使PMN–PT68/32陶瓷压电性能有一定提高。添加LiF可以使PMN–PT68/32陶瓷压电性能提高很多,其中1150℃烧结添加LiF样品的压电性能为:平面机电耦合系数(kp)约为64%;厚度机电耦合系数(kt)约为54%;压电常数(d33)约为623pC/N;机械品质因数(Qm)约为96。添加Li2CO3和LiNO3样品只发生Li+在PMN–PT68/32的B位置换并产生氧空位。添加LiF样品可以通过F–取代反应产生铅空位来补偿Li+取代产生的氧空位。因此,LiF作为助烧剂的PMN–PT68/32陶瓷的优良压电性能不仅源于低温液相烧结以及阳离子Li+的取代,而且很大程度上源于阴离子F–的取代。

关键词：铌镁酸铅–钛酸铅陶瓷压电性能锂盐烧结助剂铌铁矿预产物合成法

可见光活性[艹北]铜配位聚合物网络催化甲基丙烯酸甲酯原子转移自由基聚合

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高分子材料科学与工程 2020年第7期36卷 9-14页

作者：丁钢淡宜曹林洪江龙西南科技大学材料科学与工程学院四川绵阳621000 高分子材料工程国家重点实验室(四川大学)四川大学高分子研究所四川成都610065

以具有可见光活性的[艹北]-铜配位聚合物网络(Cu-PTC)为催化剂,实现了甲基丙烯酸甲酯(MMA)的原子转移自由基聚合。研究了催化剂/单体比例对MMA聚合行为的影响,优化了聚合条件。动力学研究显示,聚合过程符合"活性"自由基聚合特征;并且核... 详细信息

以具有可见光活性的[艹北]-铜配位聚合物网络(Cu-PTC)为催化剂,实现了甲基丙烯酸甲酯(MMA)的原子转移自由基聚合。研究了催化剂/单体比例对MMA聚合行为的影响,优化了聚合条件。动力学研究显示,聚合过程符合"活性"自由基聚合特征;并且核磁共振氢谱(^(1 )H-NMR)结果表明,Cu-PTC的微孔结构可诱导MMA的光聚合,使聚合物的立构规整性提升。进一步采用紫外光谱(UV)、电子顺磁共振波谱(EPR)及电化学研究了Cu-PTC作为光诱导催化剂催化MMA聚合的机理,结果显示,Cu-PTC受光激发产生光生电子和空穴,通过光生电子活化α-溴苯乙酸乙酯(EBP)引发剂以实现"活性"聚合。

关键词： [艹北]-铜配位聚合物网络原子转移自由基聚合可见光活性甲基丙烯酸甲酯

PMN-PT弛豫铁电陶瓷的低温烧结与压电性能

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稀有金属材料与工程 2005年第Z2期34卷 791-794页

作者：曹林洪姚熹徐卓西安交通大学电子陶瓷与器件教育部重点实验室陕西西安710049 西安交通大学电子陶瓷与器件教育部重点实验室陕西西安710049 西安交通大学电子陶瓷与器件教育部重点实验室陕西西安710049

以LiF为烧结助剂研究了PMN-PT 68/32弛豫铁电陶瓷的低温烧结和压电性能.结果表明:LiF烧结助剂完全固溶到PMN-PT陶瓷中形成具有复合钙钛矿结构的固溶体,无任何第二相存在.添加2.5%LiF烧结助剂可以使PMN-PT压电陶瓷的烧结温度从1250℃降到... 详细信息

以LiF为烧结助剂研究了PMN-PT 68/32弛豫铁电陶瓷的低温烧结和压电性能.结果表明:LiF烧结助剂完全固溶到PMN-PT陶瓷中形成具有复合钙钛矿结构的固溶体,无任何第二相存在.添加2.5%LiF烧结助剂可以使PMN-PT压电陶瓷的烧结温度从1250℃降到1000℃,而且该试样具有致密均匀的显微结构,其体积密度为7.87g/cm3,达理论密度的95%,其平面机电耦合系数为71%,压电常数为500pC/N左右,最大应变量达0.25%左右.

关键词： PMN-PT LiF 低温烧结压电性能