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以NH4HCO3和NH3·H20为沉淀剂,醇水体系为溶剂,合成了钇铝石榴石(YAG)粉体,考察了超重力场和不同醇体积分数(R)对合成YAG粉体的影响,利用X射线衍射fXRD)、热重一差示扫描同步热分析(TG—DSC)和扫描电镜(SEM)等手段对粉体进行了研究,结果表明,超重力场中制备的YAG粉末颗粒更细小,分布范围更窄,分散性更好;醇水体系作为溶剂更有利于制备分散性好,粒径小的纯相YAG粉体;最适的醇体积分数为30%-50%。当以NH4HCO3和NH3·H3O为沉淀剂,R=30%的醇水体系为溶剂,在超重力场中合成的YAG前躯体在1000℃下煅烧2h,获得了分散性好、分布范围窄、晶型完整、平均粒径约为50nm的球形YAG粉体。 相似文献
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柠檬酸-凝胶燃烧法制备钇铝石榴石(Y_3Al_5O_(12))纳米粉体的研究 总被引:1,自引:0,他引:1
透明YAG多晶陶瓷具有优良的光学、力学与化学性能,逐渐成为新一代固体激光基质材料。分散均匀、团聚轻的纳米粉体有利于制备出高度透明的激光陶瓷。以Y2O3、Al(NO3)3·9H2O和柠檬酸为原料,采用柠檬酸凝胶燃烧法制备出黑色粉体,经1100℃烧结出尺寸小于50nm的YAG粉体。采用TG-DTA、XRD、FT-IR和TEM测试手段对YAG纳米粉体进行表征,采用谢莱公式计算出不同烧结温度下的晶粒尺寸。研究结果表明:YAG的析晶温度范围为850~900℃,烧结过程中出现赝YAG相物质,1050℃转变成纯YAG相,随着热处理温度的升高,晶粒呈线性增长,纳米粉体的TEM尺寸和采用谢莱公式计算的结果相一致。 相似文献
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均相共沉淀法合成钇铝石榴石(YAG)纳米粉末的研究 总被引:6,自引:0,他引:6
透明YAG多晶陶瓷具有容易制造、成本低、尺寸大、掺杂浓度高、热导率高、耐热冲击性好、可大批量生产、易实现多层和多功能的陶瓷结构等优点,使得它作为激光介质而成为单晶的强有力的替代者.本实验以Y2O3、Al(NO3)3*9H2O、(NH4)2SO4为原料,尿素为沉淀剂,正硅酸乙酯作为添加剂,采用均相共沉淀法制备出YAG前驱体粉末,在沉淀过程中采用静电稳定、聚合物空间位阻以及共沸方法相结合有效地防止了纳米颗粒硬团聚的形成,YAG前驱体颗粒尺寸小于50nm,并对反应过程中pH值的变化进行研究.采用DTA/TG、IR、 XRD和TEM测试手段对粉末材料进行了表征,根据Scherrer公式计算出晶粒大小,研究了晶粒尺寸分布及其变化情况.研究结果表明:前驱体粉末经过1 200℃温度烧结后,全部转化YAG相,其晶粒尺寸小于50nm,随着烧结温度升高,晶粒平均尺寸增大. 相似文献
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采用低温燃烧法合成出掺钕钇铝石榴石(Nd:YAG)粉末,经模压300MPa成型,于1700℃真空烧结5h,制备出尺寸φ9mm×1mmNd:YAG透明陶瓷片.对Nd:YAG透明陶瓷片进行光透过率、场发射-环境扫描电镜测量.采用体视学原理与方法定量地研究了Nd:YAG透明陶瓷的微观结构参数和光透过率之间的关系.研究结果表明:尺寸φ9mm×1mmNd:YAG透明陶瓷片在可见光波段光透过率约为45%,在近红外光波段约为55%;随着入射光波长的增加,光透过率增加;随着晶粒三维球当径(D_(3S))的增加,光透过率增加,当D_(3S)约为20μm时,Nd:YAG透明陶瓷光透过率接近单晶理论值;随着晶粒以及单个晶粒平均比表面积的增加,光透过率降低;随着晶粒三维平均自由距离的增加,光透过率降低. 相似文献
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使用超声波-微波辅助的醇盐水解沉淀法合成了Y_3Al_5O_(12)(YAG)前驱体,加入烧结助剂及分散剂后真空烧结制备了YAG透明陶瓷,并对添加不同分散剂烧成的YAG透明陶瓷的晶相结构、微观形貌及光学性能进行了表征。结果表明:添加不同分散剂均可获得纯相YAG透明陶瓷;添加聚丙烯酸铵(NH_4PAA),晶粒之间没有明显的晶界,且气孔较大;添加柠檬酸铵(AC),晶粒分散良好,平均晶粒尺寸约为3μm。未添加分散剂时,YAG透明陶瓷在近红外波段处透光率为76%;添加NH_4PAA时,透明陶瓷透光率较低,仅为51%;而添加AC后透明陶瓷透光率可达到78%。添加AC能够细化YAG透明陶瓷晶粒,促进残余气孔排出,从而使YAG透明陶瓷获得更高的透光率。 相似文献
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钇铁石榴石(Y3Fe5O12, YIG)材料因其优异的磁性能和磁光性能在微波通信、激光技术和光纤通讯等领域具有重要应用。离子掺杂是提高YIG材料磁光性能的有效途径之一, 本研究选择离子半径适配的Bi3+掺杂改性YIG陶瓷以提高材料的磁光性能。本工作采用固相法热压烧结制备BixY3-xFe5O12 (x=0、0.3、0.6、0.9)陶瓷, 并研究Bi3+掺杂对YIG陶瓷材料相结构、微观形貌、红外透过性、磁性能以及磁光性能的影响。结果表明: 陶瓷样品均呈石榴石立方相结构; 显微结构致密, Bi3+掺杂后晶粒尺寸不同程度增大; 样品红外透过率良好, 随Bi3+掺杂量增大而降低; 陶瓷样品的法拉第旋转角随Bi3+掺杂量增加呈线性变化, Bi3+掺杂量每增加1% (原子分数), 在波长1064 nm和1550 nm处变化量分别约为-49.0 (°)/cm和-30.2 (°)/cm。Bi0.6Y2.4Fe5O12陶瓷样品在1064 nm和1550 nm波长下法拉第旋转角分别达到-703.3 (°)/cm和-461.5 (°)/cm, 绝对值远高于未掺杂YIG陶瓷的277.6 (°)/cm和172.0 (°)/cm。由此可见, 掺杂适量Bi3+可以显著增强YIG陶瓷材料的磁光性能。 相似文献
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Xingjie Fu Tiantian Wang Wenzhong Shen Miaoli Jiang Youwei Wang Qiushi Dai Da Wang Zhenping Qiu Yelong Zhang Kuirong Deng Qingguang Zeng Ning Zhao Xiangxin Guo Zheng Liu Jianjun Liu Zhangquan Peng 《Advanced materials (Deerfield Beach, Fla.)》2020,32(26):2000575
Garnet-type solid-state electrolytes (SSEs) are promising for the realization of next-generation high-energy-density Li metal batteries. However, a critical issue associated with the garnet electrolytes is the poor physical contact between the Li anode and the garnet SSE and the resultant high interfacial resistance. Here, it is reported that the Li|garnet interface challenge can be addressed by using Li metal doped with 0.5 wt% Na (denoted as Li*) and melt-casting the Li* onto the garnet SSE surface. A mechanistic study, using Li6.4La3Zr1.4Ta0.6O12 (LLZTO) as a model SSE, reveals that Li2CO3 resides within the grain boundaries of newly polished LLZTO pellet, which is difficult to remove and hinders the wetting process. The Li* melt can phase-transfer the Li2CO3 from the LLZTO grain boundary to the Li*’s top surface, and therefore facilitates the wetting process. The obtained Li*|LLZTO demonstrates a low interfacial resistance, high rate capability, and long cycle life, and can find applications in future all-solid-state batteries (e.g., Li*|LLZTO|LiFePO4). 相似文献
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Hongxing LIU Hong DENG Yan LI Yanrong LIInstitute of Microelectronics Solid State Electronics University of Electronic Science Technology of China Chengdu China 《材料科学技术学报》2004,20(5):637-638
It was focused on the applications and developments of microwave hydrothermal synthesis piezoelectric ceramic powder. The microwave hydrothermal vessel was designed and manufactured. The microwave hydrothermal synthesis system was established and the PZT piezoelectric ceramic powder was synthesized. XRD and TEM have been used to characterize the products in detail. The diameter of the PZT powder particle is from 40 to 60 nm. 相似文献
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Peng Jinhui Binner Jon Bradshaw Steven 《Journal of Materials Synthesis and Processing》2001,9(6):363-368
The use of microwave energy to initiate self-propagating, high-temperature synthesis (SHS) of Si + graphite mixtures has been investigated. The results indicate that, unlike with conventional ignition techniques, green densities in excess of 80% of theoretical can be ignited and the combustion wavefront can be crudely controlled. It was found that the induction time for ignition increased with increasing green density and that a higher microwave power level was required with the denser green pellets to achieve the same ignition time. Combustion front velocity increased with green density. The degree of densification was found to decrease with increasing green density. For a given green density, the degree of densification increased with increasing microwave power. The product contained a significant proportion of ultrafine (36–72 nm diameter) SiC whiskers; despite this, final densities as high as 83.6% of theoretical could be obtained without the use of applied pressure. This compares with the 50% densities obtained via conventional ignition techniques. 相似文献
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微波介质陶瓷粉体的合成方法研究 总被引:16,自引:3,他引:13
综述了目前合成微波介质陶瓷粉体的各种方法,包括熔盐法、微波合成法等“固相合成法”和溶胶-凝胶法、水热法、共沉淀法、Pechini法等“湿化学合成法”以及结合两者的干湿混合法。介绍了各种合成方法的原理及应用,并对它们的优缺点进行了评价。在固相法中,熔盐法具有合成温度低、合成时间短、产物纯度高、粒度相对较小等特点,同时具有操作简单、易于工业化生产的优点而具有良好的发展前景。在湿化学法中,溶胶-凝胶法由于可以实现分子水平上的混合及得到纳米级的粉体,也具有十分巨大的潜在应用价值。 相似文献
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柠檬酸-凝胶燃烧法制备钇铝石榴石(Y3A15O12)纳米粉体的研究 总被引:1,自引:0,他引:1
透明YAG多晶陶瓷具有优良的光学、力学与化学性能,逐渐成为新一代固体激光基质材料.分散均匀、团聚轻的纳米粉体有利于制备出高度透明的激光陶瓷.以Y2O3、Al(NO3)3·9H2O和柠檬酸为原料,采用柠檬酸-凝胶燃烧法制备出黑色粉体,经1100℃烧结出尺寸小于50nm的YAG粉体.采用TG-DTA、XRD、FT-IR和TEM测试手段对YAG纳米粉体进行表征,采用谢莱公式计算出不同烧结温度下的晶粒尺寸.研究结果表明:YAG的析晶温度范围为850~900℃,烧结过程中出现赝YAG相物质,1050℃转变成纯YAG相,随着热处理温度的升高,晶粒呈线性增长,纳米粉体的TEM尺寸和采用谢莱公式计算的结果相一致. 相似文献
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受激布里渊散射(SBS)和热管理限制了玻璃光纤在光纤激光器中极限输出功率的提高.钇铝石榴石(YAG)晶体光纤结合了晶体和光纤的优点,相较于玻璃光纤,它的SBS增益系数低得多,可以有效地减小非线性效应和热损伤,为光纤激光器研究提供了新的方向.YAG晶体在达到熔点(1970℃)后会迅速熔化成低粘度液体,不利于晶体光纤的制备;制备YAG晶体纤芯/玻璃包层的复合光纤是研究YAG晶体光纤的主要方法,但是存在YAG晶体纤芯玻璃化、纤芯与包层间的成分扩散以及数值孔径过大的问题;未掺杂的YAG晶体作为稀土掺杂的YAG晶体纤芯的包层生长困难,有待于进一步研究.目前多采用激光加热基座生长技术(LHPG)和微下拉法(μ-PD)制备YAG晶体光纤,且制得的光纤质量较好;对YAG晶体光纤的研究,重点在于采用折射率、热膨胀与YAG晶体相匹配的玻璃或晶体作为包层,并探索复合工艺,减小数值孔径和减少纤芯与包层间的扩散,现有文献报道的最大输出功率达到590 W.本文介绍了几种YAG晶体光纤的制备方法,对国内外关于无包层稀土掺杂YAG晶体光纤、玻璃包层稀土掺杂YAG晶体复合光纤、YAG晶体包层晶体光纤及YAG晶体光纤与传统无源光纤器件的熔接的研究现状进行了综述,并对目前的研究状况进行了总结与展望. 相似文献
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We report measurements of the refractive index of undoped yttrium aluminum garnet from 0.4 to 5.0 mum and the calculation of Sellmeier coefficients based on our data. The data differ considerably from previously published reports. The effect of the new data on the design of optical devices such as intracavity etalons for lasers is discussed. 相似文献
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通过加速旋转坩埚技术和Bi2O3/B2O3助溶剂生长技术研制新型磁光复合稀土铁石榴石单晶ReYbBiIG(Re:Tb3+、Ho3+、Y3+。从理论上解释了将两种具有相反符号法拉第温度和波长系数的掺铋稀土铁石榴石复合可以显著优化磁光性能,并成功制得具有大磁光优值、低饱和磁化强度、低近红外吸收、极小法拉第温度和波长系数的系列优质磁光单晶(如:Ho0.85Yb1.12Bi1.03Fe5O12和Tb2.06Yb0.46Bi0.48Fe5O12等)。研究表明,以新型磁光复合稀土铁石榴石单晶ReYbBiIG作为法拉第转子材料制得的新型光隔离器更适用于WDM光纤通讯系统对宽波段和温度稳定性的要求。 相似文献
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L. V. Lutsev S. M. Suturin A. M. Korovin V. E. Bursian N. S. Sokolov 《Technical Physics Letters》2018,44(7):558-561
Relaxation losses of magnetic excitations in nanoscale films of Y3Fe5O12 (YIG) were studied. The films were obtained by laser molecular-beam epitaxy (LMBE). Ferromagnetic resonance linewidth ΔH was found to increase sharply as the temperature decreased from 300 to 77 K. The observed growth of ΔH is explained by typical relaxation processes caused by the presence of Fe2+ ions. This effect is not observed in thick films of YIG grown by liquid-phase epitaxy and containing Pb4+ ions, and, hence, we have concluded that the presence of acceptor ions in YIG films obtained by LMBE will facilitate decreasing the concentration of Fe2+ ions and, a result, diminishing relaxation losses. 相似文献