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基于光学辐照方法调控荧光光强及显色性

功能材料 2024年第6期55卷 6160-6166页

作者：陈浩惠增哲陈玉丽龙伟张小丽丁礼磊安康学院电子与信息工程学院陕西安康725000 西安工业大学材料与化工学院西安710016

随着信息技术的发展,产品防伪和信息保护已成为许多行业密切关注的问题,研发防伪复杂度高的光学防伪材料受到研究人员越来越多的关注。选用Er^(3+)掺杂Ca_(2)SnO_(4)基体,发现Er^(3+)掺杂将占据4h位阳离子位置,在提升材料的光学性能过程... 详细信息

随着信息技术的发展,产品防伪和信息保护已成为许多行业密切关注的问题,研发防伪复杂度高的光学防伪材料受到研究人员越来越多的关注。选用Er^(3+)掺杂Ca_(2)SnO_(4)基体,发现Er^(3+)掺杂将占据4h位阳离子位置,在提升材料的光学性能过程中,具有两方面的作用。一方面,Er^(3+)作为发光中心,380 nm激发下,分别产生以550 nm为主峰的绿光发射和以671 nm为主峰的红光发射。另一方面,非等价的取代掺杂在材料中引入缺陷陷阱捕获载流子形成色心,有助于材料具备光致变色能力。在UV光源辐照后,材料的光致发光光强和荧光寿命表现出衰减调制现象。同时,材料的荧光显色参数如CIE色度坐标、色纯度、相关色温也会因UV光源辐照被调控。最后,借助能量传递理论,分析得到由发光中心向色心的能量传递是材料荧光调控现象产生的原因。上述研究表明通过外部光源照射的方式能够对Er^(3+)掺杂Ca_(2)SnO_(4)荧光光强及显色性产生调控,在光学防伪领域具有应用潜力。

关键词：光学防伪光强调控光致发光显色调控

Ca_(2)SnO_(4):Eu3+陶瓷的光致变色及光强调控特性研究

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功能材料 2024年第1期55卷 1117-1123页

作者：陈浩惠增哲郭菲菲龙伟张小丽方频阳李晓娟西安工业大学材料与化工学院西安710021 安康学院电子与信息工程学院陕西安康725000

开发光辐射响应好、稳定性强的光致变色材料是无机光致变色材料研究的一大目标。研究采用高温固相反应法制备了稀土离子Eu^(3+)掺杂的光致变色陶瓷Ca_(2.02-x)SnO_(4):xEu^(3+)。对陶瓷的光致变色行为展开研究,发现在290 nm光照下着色... 详细信息

开发光辐射响应好、稳定性强的光致变色材料是无机光致变色材料研究的一大目标。研究采用高温固相反应法制备了稀土离子Eu^(3+)掺杂的光致变色陶瓷Ca_(2.02-x)SnO_(4):xEu^(3+)。对陶瓷的光致变色行为展开研究,发现在290 nm光照下着色效果最好,陶瓷由白色变为灰色。440 nm光照8 min后着色陶瓷颜色基本恢复,或者将着色陶瓷加热至623 K后灰色完全消失。光致发光性能研究表明395、466和534 nm可激发出以617 nm为主的红色光发射。研究了陶瓷的光强调控特性,发现290 nm光照射能使陶瓷的发射光谱强度显著降低,617 nm处有最高着色光强调制率86.9%。经过10个循环的着色-漂白实验,陶瓷光强调控性能保持稳定,表现出良好的可逆性。陶瓷的光致变色行为和光强调控行为表现出明显的特征UV波长响应和UV光辐射累积响应特点,表明该材料有望应用于光辐射剂量探测领域。

关键词：光致变色光强度光致发光光辐射探测可逆性

Abnormal dielectric characteristics of PMN- 32% PT single crystal under dc bias

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Chinese Science Bulletin 2003年第19期48卷 2038-2040页

作者： xi zengzhe LI Zhenrong XU Zhuo ZHANG Liangying YAO xi Functional Materials Research Laboratory Tongji University Shanghai 200092. China Key Laboratory of the Ministry of Education Xi'an Jiaotong University Xi'an 710049 China

The dielectric properties and phase transition behavior of the [001] and [111] oriented PMN-32%PT single crystal under the different dc bias (E) have been investigated as a function of temperatures. Under the application of dc bias ranging from 1.5 to 4.0 kV/cm, the dielectric spectrum of a [001] oriented single crystal showed an abnormal dielectric peak within the rhombic phase-stable temperature range. However, this peak disappeared at E>4.0 kV/cm and was not yet found in the [111] oriented single crystal. The abnormal dielectric peak was attributed to the filed-induced phase transition.

关键词：不规则电介质 PMN-PT 单晶铁电体相转换

Growth and property enhancement of Er^(3+)-doped 0.68Pb(Mg_(1/3)Nb_(2/3))O_3-0.32PbTiO_3 single crystal

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Journal of Rare Earths 2018年第8期36卷 832-837页

作者： Wei Long xing Chu zengzhe xi Pinyang Fang xiaojuan Li Wenwu Cao Shaanxi Key Laboratory of Photoelectric Functional Materials and Devices School of Materials and Chemical Engineering Xi'an Technological University Condensed Matter Science and Technology Institute Harbin Institute of Technology Department of Mathematics and Materials Research Institute The Pennsylvania State University

Er^3＋-modified 0.68 Pb（Mg（1/3）Nb（2/3））O3-0.32 PbTiO3（PMN-32 PT） single crystals were grown by using the flux method. The growth mechanism of the crystal and influences of Er^3＋ ions on phase structure,electrical and optical properties were investigated. Results reveal that the crystals are still pure perovskite structure with Er3＋ ions doping, but lattice enlarges slightly. The coercive electric field is increased from 4.83 to 6.37 kV/cm for [100]-oriented crystals comparing to undoped PMN-32 PT single ***, the crystal exhibits upconversion emission properties. Green（531 and 552 nm） and red（670 nm） emission bands are recorded under the excitation of 980 nm diode laser, which correspond to the ^2 H（11/2）→^4 I（15/2）, ^4 S（3/2）→^4 I（15/2） and ^4 F（9/2）→^4 I（15/2） transitions of Er^3＋ ions. Our results show the feasibility of using this crystal in photoelectric multifunctional devices.

关键词： PMN-PT single crystal Er^3+ ion doping Flux method Upconversion Rare earths

Synthesis of antiferroelectric (Bi_(0.534)Na_(0.5))_(0.94)Ba_(0.06)TiO_3 ceramics with high phase transition temperature and broad temperature range by a solid-state reaction method

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Chinese Science Bulletin 2013年第23期58卷 2893-2897页

作者： LI xiaoJuan xi zengzhe LONG Wei FANG PinYang School of Materials and Chemical Engineering Xi'an Technological University

Antiferroelectric 0.94(Bi 0.534 Na 0.5 )TiO 3 -0.06BaTiO 3 ceramics were prepared using a solid-state reaction method, involving the addition of excessive amounts of Bi2O3 . The resulting ceramics featured a very high phase transition temperature (Tm～330°C), from the antiferroelectric to the paraelectric phase, and a low depolarization temperature (Td<25°C). The broad temperature range, within which antiferroelectric properties are retained, of the prepared materials indicates their higher potential over lead-based antiferroelectric ceramics such as PZT-based materials that exhibit a lower T m ≤170°C. The lower Td and higher T m obtained val- ues, relative to those reported in the literature, are believed to be due to the formation of A-site vacancies originating from the incorporation of excess Bi into the perovskite structure of the studied sample. In addition, the synthesized sample shows a high dielectric constant of ～1460, in a temperature range of 50-150°C at 1 kHz, and a high energy storage density of 0.71 J/cm 3 , which is an asset in energy storage capacitor applications.

关键词：陶瓷制备温度范围相变温度固态反应反铁电合成 PZT材料钙钛矿结构

Entropy as a selection rule for crystal growth in undercooled binary eutectic melts

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Chinese Science Bulletin 2009年第6期54卷 1012-1018页

作者： LU YiPing xi zengzhe YANG GenCang LIN xin ZHOU YaoHe State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi'an 710072 China School of Materials and Chemical Engineering Xi'an Technological University Xi'an 710032 China

A solution entropy model was developed for the undercooled binary eutectic alloy systems. As an ex-tension of Taylor and Fidler et al.'s model, the present model considered the change of phase compo-sition with the increase of undercooling. Furthermore, the sub-regular solution model and the interac-tion parameter (IAB) were also introduced. In this paper, the extended model is used to calculate the solution entropy for binary eutectic phases under the undercooled condition, and the application scope of the model is also extended. Not only the growth manner of eutectic phases, but also the transition of morphologies may be predicted and explained by calculating the solution entropy of eutectic phases under the non-equilibrium condition with the developed model. Experimental results show that the developed model is valid for the undercooled Ni-Si and Ni-Sn eutectic alloy systems.

关键词：熵模型共晶相二元晶体生长选择规则熔体相互作用参数正规溶液模型

Preparation and characterization of SiO2 non-catalytic nucleation coating for the solidification of undercooled melt

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Progress in Natural Science:Materials International 2003年第2期 47-51页

作者： xi zengzhe, YAO xi and ZHANG Liangying(Functional Materials Research Laboratory of Tongji University, Shanghai 200092, China) Functional Materials Research Laboratory of Tongji University Shanghai 200092 China

Abstract SiO2non-catalytic nucleation films were coated onto a ceramic substrate and the inner surface of a ceramic crucible by theSol-Gel method. The surface morphology of the coatings was characterized with an atomic force microscope and a scanning electronic mi-croscope. The non-catalytic effect of the coating on the heterogeneous nucleation of metal melts was tested through measuring the nucle-ation undercooling. Investigation results indicated that the prepared coating could act as a baffle-wall to prevent the metal melt from nucle-ating heterogeneously on the inner surface of the crystalline crucible. The tiny holes with a diameter below 2 μm and heaves on the coatingsurface have no evident effect on the undercooling of metal melts. For a poly-layer coating, the super-layer can cover the cracks in the sub-layers, which prevents the cracks in the coating from spreading in the direction vertical to the coating layers and thus eliminates the effectof cracks on the coating.

关键词： high undercooling catalytic nucleation non-crystalline coating sol-gel bismuth atomic force microscope.

DIELECTRIC PROPERTIES AND PHASE TRANSITION OF PMN32%PT SINGLE CRYSTAL UNDER DC ELECTRIC FIELD

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DIELECTRIC PROPERTIES AND PHASE TRANSITION OF PMN32%PT SINGL...

第8届国际材联电子材料国际研讨会

作者： Zhenrong Li Zhuo Xu zengzhe xi xi YaoElectronic Materials Research Laboratory xi’an Jiaotong University xi’an 710049 China

＜正＞ The temperature dependencies of dielectric properties for PMN32%PT single crystal under different DC electric field （E） have been investigated. The dielectric responses and phase transitions of this single crystal are provided. With increasing of electric field, phase transition temperatures of rhombohedral to

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高温溶液法生长PZN-9PT弛豫铁电晶体

压电与声光 2011年第1期33卷 136-138页

作者：龙伟惠增哲李晓娟尹珂西安工业大学材料与化工学院陕西西安710032

采用高温溶液法制备了PZN-9PT晶体,研究了晶体相结构、生长形态,表征了其介电、压电和电滞回线等部分电学性能。结果表明,采用高温溶液法可制备出纯钙钛矿结构的PZN-9PT单晶,晶体呈淡黄色多面体形态,晶粒表面的台阶均为直形生长台阶;其... 详细信息

采用高温溶液法制备了PZN-9PT晶体,研究了晶体相结构、生长形态,表征了其介电、压电和电滞回线等部分电学性能。结果表明,采用高温溶液法可制备出纯钙钛矿结构的PZN-9PT单晶,晶体呈淡黄色多面体形态,晶粒表面的台阶均为直形生长台阶;其三方-四方相转变温度为89℃,居里温度为175℃;[221]切型PZN-9PT单晶的压电常数为230 pC/N,矫顽场为8.8 kV/cm。

关键词： PZN-9PT晶体高温溶液法生长台阶压电弛豫铁电体