共查询到18条相似文献,搜索用时 82 毫秒
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均匀沉淀法制备锡酸锌与锡酸锌包覆纳米碳酸钙的研究 总被引:1,自引:0,他引:1
以均匀沉淀法制备了羟基锡酸锌和羟基锡酸锌包覆纳米碳酸钙,利用超声分散和共沸蒸馏对所得产物处理后,经高温煅烧得锡酸锌包覆纳米碳酸钙粉体.采用XRD,TG-DTA对羟基锡酸锌及羟基锡酸锌包覆纳米碳酸钙的煅烧产物进行分析,确定合成锡酸锌和锡酸锌包覆纳米碳酸钙的最佳煅烧温度为500 ℃,最佳煅烧时间为3 h.X射线光电子能谱(XPS)分析表明,锡酸锌已包覆在纳米碳酸钙表面,透射电子显微镜(TEM)结果表明,锡酸锌包覆纳米碳酸钙的粒径在40~60 nm. 相似文献
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助熔剂法生长的锆钛锡酸铅镧(PLZST)晶体及生长余料的组分分析 总被引:1,自引:0,他引:1
以PbO-PbF2复合体作为助熔剂,采有助熔剂自发成核缓冷法率先制备出成分为(Pb0.94La0.04)(Zr0.37Ti0.18Sn0.45)O3的驰豫型复合钙钛矿结构锆钛锡酸铅镧(PLZST)晶体,合适的生长工艺为:助熔剂中PbO与PbF2的摩尔比为0.55:0.45,原料与助熔剂的摩尔比为1:1,保温温度1250℃,保温时间12h,快降温速率为50-100℃/h,慢降温速率为1-5℃/h,快速降温与慢速降温的转变温度为1150℃,本工作对晶体及晶体生长余料中的组分进行了分析,结果表明:对一定组成的初始配料,PLZST晶体组成相对富La,Ti和Zr,生长后的余料相对富Sn,PLZST晶体中存在两种包裹体缺陷,晶体除包裹体以外各元素分布均匀,生长余料中各元素分布较均匀,存在某些元素的相对富集区域。 相似文献
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《Ceramics International》2019,45(14):17420-17428
In this study, electrically conductive perovskite lanthanum-doped barium stannate, LaxBa1-x SnO3-δ (x = 0, 0.05, 0.1 and 0.15) ceramics were synthesized through polymerized complex method. The evolution of BaSnO3 phase with temperature and effect of La doping was investigated. Doping of La increased the lattice parameter from 4.1165 to 4.1208 Å, up to solubility limit (x = 0.1); doping further, secondary phase La2Sn2O7 appeared. BaSnO3 phase crystallization initiated at ∼528 °C from the reaction of BaCO3 and SnO2 and was retarded by La doping causing an increment in phase formation temperature from 528.4 to 531.1 °C. Fourier transform infrared spectroscopy evidence substantial increment in (SnO3)2- absorption band with temperature strengthening diffraction responses. An incremental response in the electrical conductivity was observed by La doping with a maximum value of ∼25 S cm−1, attributed to the generation of charge carriers by substitution of Ba with La ion and oxygen vacancies. In parallel, generated charge carriers also contributed towards the ionic reduction of Sn4+ to Sn2+ aiding the lattice enhancement. La-doped BaSnO3 ceramics can have a potential application in optoelectronic, thermoelectric devices and humidity sensors. 相似文献
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锡酸锌由于具有较高的电子迁移率、稳定性、高电导率,优异的吸附性能、光学性能和阻燃抑烟性能等特性,近年来逐渐受到科研人员的关注。本文介绍了锡酸锌纳米颗粒的制备方法(水热法、化学沉淀法、固相化学合成法、微波合成法、溶胶-凝胶法、模板法等)、形貌结构(颗粒状、立方体、球形、八面体、纳米棒、片状、纳米花状等)、粒径及其在不同领域(锂电负极材料、气敏材料、电触头材料、DSSC阳极、光催化、阻燃等)的应用研究进展,分析了利用不同锡化合物原料、不同方法制备锡酸锌纳米颗粒的原理、制备条件和产品特性,指出了每种制备方法的优缺点及每种制备方法中不同结构的形成机理,以及不同结构是如何对Zn2SnO4相关性能产生影响的。文章指出如何高效可控制备特定形貌和晶粒尺寸的锡酸锌是锡酸锌纳米材料未来的发展方向。 相似文献
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以湿法制得的斜方晶型三氧化二锑(Sb2O3)为原料,采用真空加热法制备了立方晶型的三氧化二锑。采用X射线衍射分析(XRD)和扫描电镜(SEM)对产物进行了表征,研究了体系压强、加热温度、加热时间对三氧化二锑晶型与粒度的影响。结果表明:当加热温度升高时,三氧化二锑由斜方晶型逐渐转变为立方晶型;但当加热温度升高至450 ℃时,已经全部转变为立方晶型的三氧化二锑中,部分立方晶型又开始转变为斜方晶型;随着加热温度的升高,样品团聚程度增加,样品的平均粒度逐渐增大。随着体系压强的下降和加热时间的延长,三氧化二锑由斜方晶型逐渐转变成立方晶型。但体系压强的下降,会增大样品团聚程度以及样品的平均粒度;加热时间延长,样品的平均粒度也逐渐增大。 相似文献
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电镀锡渣制备氯化亚锡和锡酸钠 总被引:2,自引:0,他引:2
介绍了从电镀别针厂产生的大量锡渣废料中制取氯化亚锡和锡酸钠的原理、工艺流程和工艺条件。讨论了温度、pH值和氧化剂对酸解、碱解反应的影响。实验表明 ,采用浓盐酸和氢氧化钠处理电镀锡渣的工艺流程简单 ,设备简单 ,条件容易控制 ,不但处理了大量含锡废渣 ,而且制取了合格的氯化亚锡和锡酸钠产品 ,回收率达 70 %以上 ,使电镀锡达到循环利用的目的 ,取得了明显的经济效益。 相似文献
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提出了一种新的测量碱性镀锡液中锡酸钠含量的方法。阐述了方法的原理腑雇简便、终点变色明显、准确度高、应用效果好。 相似文献
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通过直接沉淀法制备了羟基锡酸锌(ZHS)和羟基锡酸锌包覆黏土(ZHS/clay),经煅烧得到锡酸锌(ZS)和锡酸锌包覆黏土(ZS/clay)。采用X射线衍射(XRD)、扫描电镜(SEM)对产品结构进行表征。实验表明,常温反应4 h制得的ZHS产率较高、晶粒尺寸较规整,ZHS经煅烧制得的ZS为非晶结构,最终包覆产物ZS/clay的包覆形貌清晰。将ZS/clay作为三氧化二锑替代品,应用于十溴二苯乙烷(DBDPE)、三氧化二锑协同阻燃聚丙烯(PP)体系中,当替代50%三氧化二锑时,复合材料垂直燃烧等级可达V-0级,氧指数为23.3%,抗冲击强度为13.18 kJ/m2,接近未使用替代品数据。 相似文献
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Shi Chen Zhi Liang Huang Chang Lian Chen Mian Lu Chang Sheng Wu Yuan Jiang 《International Journal of Applied Ceramic Technology》2021,18(3):605-614
Vanadium doped La9.33Si6−xVxO26+0.5x (x = 0.5, 1.0, 1.5) (LSVO) electrolyte powder was prepared by combustion method at 600°C for 5-7 min. The powder was sintered at 1500°C for 3 hours to prepare LSVO ceramics. XPS, IR, XRD, and EIS analysis show that V5+ doping replaces Si4+ in [SiO4] to form [Si(V)O4] tetrahedron. With the increase in x, the lattice volume increase. When x = 2.0, the LaVO4 phase was formed, indicating that the limit doping amount of V5+ replacing Si4+ is x ≤ 1.5. The conductivity of LSVO increases significantly with the increase in x (x ≤ 1.0), which attributed to the defect reaction caused by V5+ doping. The addition of the interstitial oxygen Oi* in 63 channels and the increase of lattice volume leads to increased conductivity. When x = 1.0, the highest conductivity is 1.46 × 10−2 S·cm−1 (800°C). The doping enhancement conductivity mechanism is the Interstitial oxygen defect-Lattice volume composite enhancement mechanism. 相似文献
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Guang Yang Xiaoxiao Mao Duojin Wang Hongfei Chen Bin Liu Yuanyuan Cui Hongjie Luo Yanfeng Gao 《Journal of the American Ceramic Society》2017,100(9):4232-4239
Columnar lanthanum zirconate (LZ) films were deposited by laser chemical vapor deposition (LCVD). The effects of deposition conditions, preheat temperature and laser power, on crystal structure, morphology, and deposition rate were investigated. A large region in the terms of preheat temperature and laser power for the formation of cubic pyrochlore‐structured LZ films was mapped under a fixed total pressure of 950 Pa. The morphology of LZ films without laser irradiation showed a dense and glass‐like structure with a flat cauliflower surface. It was changed into a columnar structure with an unflat cauliflower surface by low‐power laser irradiation during deposition process. The transformation occurred once a critical laser power beyond 16 W/cm2. Thus, the effect of laser on the deposition of LZ films was a result of double‐side action including both pyrolytic effect and photolytic effect. Plasma gas around the substrate resulted in significant increases in deposition temperature and deposition rate due to self‐propagating high‐temperature reactions between the precursors and O2. The maximum deposition rate can reach 250 μm/h by LCVD. 相似文献