共查询到20条相似文献，搜索用时 281 毫秒
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运用脉冲激光沉积方法,在Pt(111)基片上沉积制备Hf0.5Zr0.5O2铁电薄膜。通过对X射线衍射(XRD)分析表明,薄膜的正交相随衬底温度升高而增强,随薄膜厚度增加而减小。P-E电滞回线实验表明,提高衬底温度有助于增强薄膜铁电性能。400℃氧气中原位退火后薄膜剩余极化(2Pr)达到8μC/cm2。5V以下薄膜漏电流密度为3.2×10-6A/cm2。Hf0.5Zr0.5O2薄膜的疲劳特性测试表明,在经过2×109次反转后可参与翻转总极化值有一定下降。 相似文献
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生长了铁掺杂(质量分数分别为25×10-6,50×10-6,100×10-6以及200 × 10-6)的近化学配比铌酸锂(SLN)晶体.用中心波长为532 nm的半导体激光器对晶体进行了二波耦合实验,测得了二波耦合的相应时间和有效增益系数随掺杂浓度、入射光总光强、写入光光强比以及入射光偏振方向的变化情况.实验结果表明,掺杂浓度越高,总入射光强越大,入射光光强比越小,都能导致响应时间减小,并且e光的响应时间要小于o光的响应时间;入射光光强比越大,有效增益系数越大,e光的有效增益系数要大于o光,而掺杂浓度对有效增益系数没有明显的影响. 相似文献
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以LaNiO3做缓冲层,用射频磁控溅射法在SiO2/Si(100)衬底上制备出0.9Pb(Sc0.5Ta0.5)O3-0.1PbTiO3/PbTiO3铁电多层薄膜.采用两步法在峰值温度750℃对薄膜进行退火.通过电滞回线和漏电流曲线对薄膜的铁电性能进行了测量.研究发现,原位生长的薄膜已经具备了较好的铁电性,这为(1-x)Pb(Sc0.5Ta0.5)O3-x0.1PbTiO3薄膜的低温制备提供了可能性.经过退火后,薄膜的铁电性略有下降,高温下铅的损失可以很好的解释这一现象. 相似文献
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《绵阳师范学院学报》2015,(8):6-9
以LaNiO3做缓冲层,用射频磁控溅射法在SiO2/Si(100)衬底上制备出0.9Pb(Sc0.5Ta0.5)O3-0.1PbTiO3铁电薄膜.采用两步法在峰值温度750℃对薄膜进行退火.分析了薄膜的漏电流机制,研究表明,薄膜漏电流在低场强下(<32kV/cm)符合欧姆(热电子发射)导电机制并受到晶界限制行为的影响,在中场强下(3285kV/cm)空间电荷限制电流(SCLC)机制占据优势,在高场强下(8585kV/cm)空间电荷限制电流(SCLC)机制占据优势,在高场强下(85100kV/cm)富勒-诺丁海姆(FN)隧穿机制起主导作用. 相似文献
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《商洛学院学报》2017,(2)
采用溶胶-凝胶法提拉镀膜制备Sn掺杂ZnO薄膜,研究了空气退火、高真空退火(10-2Pa)、低真空退火(1 Pa)和循环退火四种条件下Sn掺杂浓度对SZO薄膜光电性能的影响。结果表明:四种退火条件下不同Sn掺杂浓度时制备的SZO薄膜均为纤锌矿结构且具有C轴择优取向生长特性,当Sn掺杂浓度为5 at.%时SZO薄膜的结晶生长最好。高真空退火条件下Sn掺杂浓度为3 at.%时,电学性能最优,其电阻率可达到5.4×10(-2)Ω·cm。当Sn掺杂浓度小于3 at.%时,薄膜的可见光区平均透过率均大于85%,当掺杂浓度高于3 at.%时,薄膜的透过率随着掺杂浓度的增大而降低。 相似文献
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5-磺基水杨酸增敏化学发光分析法同时测定两种价态铁 总被引：1，自引：0，他引：1
用5—磺基水杨酸增敏鲁米诺—溶解氧—Fe2+—铜锌还原柱体系化学发光强度,同时测定两种价态的铁,使Fe2+和Fe3+的测定灵敏度均提高了10倍. Fe2+ 和Fe3+的线性范围均为110-5～110-10mol/L,检出限分别为2.810-11mol/和3.510-11 ,RSD分别为3.5%和3.9% . 此法用于水样中两种价态的铁的测定,结果令人满意. 相似文献
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孙百虎 《石家庄职业技术学院学报》2014,(2):13-16
以FeSO4为原料,NaOH为沉淀剂,加入添加剂构橼酸,用空气氧化法合成纳米铁氧化物,在不同pH值下考查添加枸橼酸对纳米铁氧化物形成的影响.试验结果表明,当pH=8～9时,少量构橼酸有利于铁氧化物品体的生长;随着枸橼酸浓度的增大,铁氧化物结晶粒子半径逐渐减小,最终铁氧化物品体消失. 相似文献
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铁作为一种变价金属,是高考命题的热点.在离子共存、离子方程式、元素化合物推断、化合物成分分析、撂究性实验、金属的腐蚀中铁充当重要的角色,特别是以铁元素知识为载体,在化学实验、物质推断和化学计算(尤其是氧化还原的计算)都有许多亮点试题.本文从七个方面,系统研究2008年高考涉及铁元素知识的化学试题,展现铁元素的"主角"风采. 相似文献
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杨晓翠 《通化师范学院学报》2022,(12):24-28
该文基于密度泛函理论(DFT)的 CASTEP 软件包,对掺杂不同浓度 La 的 LiMPO4(M=Fe,Mn)的晶胞结构和 Li+扩散进行研究 . 通过对超胞内的 Fe 和 Mn 进行替换,使 La 的掺杂浓度分别为1/16、1/8 和 1/4. 对比晶格常数发现,伴随 La 浓度的增加晶胞常数 a 增大 . 比较不同浓度掺杂体系带隙的变化和费米面附近的态密度图,发现 Fe 和 Mn 原子价电子数目的不同是导致体系电子结构不同的根本原因 . 通过构建 Li 空位模拟 Li+扩散的始末状态,研究不同浓度 La 掺杂对扩散势垒和扩散系数(扩散速率)的影响,发现 LiFePO4与 LiMnPO4均随着 La 掺杂浓度的增加 Li+扩散速率降低;La 掺杂浓度为 1/16 时 LiFePO4体系中 Li+的扩散速率具有最大值 . 相似文献
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Ba0.6Sr0.4TiO3 （BST） thin films with and without HfO 2 buffer layer were fabricated on Pt/Ti/SiO2/Si substrates by pulsed laser deposition. Dependences of HfO 2 thickness on the dielectric property and leakage current of BST thin films were focused. The dielectric constant of BST thin films increased and then decreased with the increase of HfO 2 thickness, while the dielectric relaxation was gradually improved. The loss tangent and leakage current under positive bias decreased with the HfO 2 thickness increasing. The leakage current analysis based on the Schottky emission indicated an improvement of the BST/Pt interface with HfO 2 buffer layer. The loss tangent, tunability and figure of merit of optimized HfO 2 buffered BST thin film achieved 0.009 8, 21.91% （E max = 200 kV/cm）, 22.40 at 10 6 Hz, respectively. 相似文献
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Dissolved oxygen sensor based on sol-gel matrix doped with tris(2,2’-bipyridine)ruthenium dichloride
To establish a immobilization method of oxygen sensitive dye, a dissolved oxygen sensor based on a sol-gel matrix doped with ruthenium complex ([Ru(bpy)3]2+) as the oxygen-sensitive material is reported. The results indicate that the I0 /I100 value of the [Ru(bpy)3]2+-doped in tetraethylorthosilane (TEOS) composite films are estimated to be 10.6, where I0 and I100 correspond to the detected fluorescence intensities in pure nitrogen saturated water and pure oxygen saturated water, respectively. Also, the Stern-Volmer plot shows a very good linearity at low dissolved oxygen concentrations. The response time of the composite films is 5 s upon switching from nitrogen saturated water to oxygen saturated water and 10 s from oxygen saturated water to nitrogen saturated water. The dissolved oxygen sensors based on the ruthenium complex/TEOS composite films exhibit greater sensitivity, stability and faster response time as compared to the existing ones. Furthermore, the thin films possess greatly minimized dye leaching effect. 相似文献
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Jie Jiang Xue-tao Wang Li-ping Zhu Li-qiang Zhang Zhi-guo Yang Zhi-zhen Ye 《浙江大学学报(A卷英文版)》2011,12(7):561-566
ZnNiO thin films with different contents of Ni (0–10 at.%) were fabricated on quartz and Si (100) substrates by pulsed laser deposition (PLD). We measured the samples by X-ray diffraction (XRD), field-emission scanning electron microscope (FE-SEM), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible spectrometer (UV-VIS), and Hall testing. When the Ni contents were below 3 at.%, partial Zn2+ ions were replaced by the Ni2+ ions without forming any other phases, which enhanced the conductivity of the film. When the Ni contents were above 3 at.%, Ni ions were at the interstitial sites, and Ni-related clusters and defects were able to emerge in the films, resulting in a worsening of electrical and optical properties. A ferromagnetic hysteresis with a coercive force of approximately 30 Oe was observed in the ZnNiO film with a Ni content of 3 at.% at room temperature. 相似文献
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研究了溴化十六烷基吡啶存在下硫酸铵—碘化钾—结晶紫体系浮选分离铋的行为及其与常见离子分离的条件.结果表明,在O.5mL溴化十六烷基吡啶(10g/L)存在下,当固体(NH_4)_2SO_4、碘化钾溶液(0.1mol/L)和结晶紫溶液(0.001mol/L)的用量分别为1.0g、1.0mL、1. 0mL时,控制pH值为7.0,Bi~(3+)可被该体系浮选,而常见离子Zn~(2+)、Fe~(2+)、Co~(2+)、Ni~(2+)、Al~(3+)不被浮选,据此实现了Bi~(3+)与这些离子的定量分离,对合成水样进行了定量浮选分离测定,结果满意。 相似文献
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文中采用乙烯做还原剂,向采用浸渍法制备的Mn—ZSM-5催化剂中加入CaH2作为助荆,考察了助剂的量、活化温度及空速对其活性的影响．实验结果表明,Mn—ZSM-5／10％CaH2在400％He气氛中活化后,在24000h^-1的空速下活性依然很好．并采用XRD、NH3-TPD对Mn—ZSM-5／10％CaH2进行表征． 相似文献
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Nano-particles lanthanum-modified lead titanate (PLT) thin films are grown on Pt/Ti/SiO2/Si substrate by liquid source misted chemical deposition (LSMCD). PLT films are deposited for 4-8 times, and thenannealed at various temperature. XRD and SEM show that the prepared films have good crystallization behavior and perovskite structure. The crystallite is about 60nm. The deposition speed is 3nm/min. This deposition method can exactly control stoichiometry ratios, doping concentration ratio and thickness of PLT thin films. The best annealing process is to bake at 300℃ for 10min and anneal at 600℃ for 1h. 相似文献
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INTRODUCTION Monocrystalline SBN (Strontium barium nio-bium, SrxBa1?xNb2O6, denoted SBNx?100, where 0.25≤x≤0.75) solid solution, is currently being inves-tigated as potential material for many micro-device applications, such as piezoelectric infrared detectors, piezoelectric, electro-optic modulators, and holo-graphic storage (Koch et al., 1998), because SBN has one of the largest known linear electro-optic coeffi-cients (r33=1300 pm/V for SBN75), two orders of magnitude larger th… 相似文献
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Pt/Ti bottom electrodes were fabricated on SiO2/Si substrates by magnetron dual-facing-target sputtering system. Lead zirconate titanate(PZT) thin films were deposited on Pt/Ti/ SiO2/Si substrates by radio frequency (RF) magnetron sputtering system. The thickness of PZT thin films which were deposited for 5 h was about 800 nm. XRD spectra show that PZT thin films deposited in Ar ambience and rapid-thermal-annealed for 20 min at 700 ℃ have good crystallization behavior and perovskite structure. AFM micrographs show that mean diameter of crystallites is 70 nm and surface structures of PZT thin films are uniform and dense. Raw mean, root mean square roughness and mean roughness of PZT thin films are 34.357 nm, 2.479 nm and 1.954 nm respectively. As test frequency is 1 kHz, dielectric constant of PZT thin films is 327.6. Electric hysteresis loop shows that coercive field strength, residual polarization strength and spontaneous polarization strength of PZT thin films are 50 kV/cm, 10 μC/cm2 and 13 μC/cm2 respectively. 相似文献