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1.
崔万秋  尹健 《物理学报》1987,36(9):1187-1193
本文研究了非晶态锂离子导体29.6P2O5-44.4Li2O-26.0LiCl和36.3P2O5-44.4Li2O-15.1LiCl-4.2Al2O3的阻抗谱,给出了测量盒系统的等效电路,得出了界面阻抗的色散关系。在一定条件下,此界面阻抗过渡到恒相角阻抗。 关键词:  相似文献   

2.
用核磁共振对非晶态中B3+离子的微观结构进行了测定,结合Raman光谱的研究,对Li2O-B2O3-P2O5系统非晶态的性能(电导率、密度等)在P2O5/B2O3比约等于1时产生极值的原因从理论上作了阐明。  相似文献   

3.
苏昉  苏骏  金嗣炤 《物理学报》1992,41(3):448-458
对两种非晶态B2O3-0.7Li2O-0.7LiCl-xAl2O3-0.1V2O5(x=0.05和0.15),用差热分析、电导率测量、X射线衍射和电子自旋共振进行研究,发现:1)V2O5不仅作非晶网络形成剂,而且改变了晶化过程;2)对B2O3-Li2关键词:  相似文献   

4.
车广灿  陈立泉 《物理学报》1981,30(9):1219-1224
本文用差热分析和X射线衍射方法对Li2SO4-Li2B2O4和Li2SO4-[NH4]2SO4两个赝二元系相图进行了研究。Li2SO4-Li2B2O4是共晶体系,共晶温度为720℃ 关键词:  相似文献   

5.
本文用X射线和差热分析方法对BaO-Li2O-B2O3三元系中的两个截面:BaB2O4-Li2B2O4和BaB2O4-Li2O作了研究。在BaB2O4-Li2B2O4赝二元系中发现了一个新的化合物4BaB2O4·Li2B2O4。化合物在930±3℃由包晶反应形成,并与Li2B2O4形成共晶反应。共晶温度为797±3℃,共晶点组分为79mol%Li2B2O4。在BaB2O4-Li2O截面中也存在化合物4BaB2O4·Li2B2O4,其包晶反应温度从930±3℃随Li2O含量增加下降到908±3℃。在组分60mol%Li2O处形成另一个新的化合物2BaB2O4·3Li2O。该化合物在630±3℃也是由包晶反应形成,并与Li2O和Li2CO3分别形成共晶反应,共晶温度分别为400±3℃和612±3℃。在BaB2O4-Li2B2O4和BaB2O4-Li2O体系中都没有观察到固溶体。用计算机程序分别对化合物4BaB2O4·Li2B2O4和2BaB2O4·3Li2O的X射线粉末衍射图案进行了指标化,其结果:4BaB2O4·Li2B2O4的空间群为Pmma,a=13.033?,b=14.630?,c=4.247?,每个单胞包含两个化合式单位;2BaB2O4·3Li2O的空间群为Pmmm,a=4.814?,b=9.897?,c=11.523?,每个单胞也含有两个化合式单位。 关键词:  相似文献   

6.
杨原  侯建国  俞文海 《物理学报》1990,39(4):561-564
对非晶态Cu+快离子导体0.4CuI-0.3Cu2O-0.3P2O5在等温热处理条件下测量离子电导率的同时,进行了X射线衍射(XRD)与扫描电子显微术(SEM)研究。结果表明:初始的非晶态材料是分相的;随着等温热处理,分离的非晶第二相逐渐消失,并发生非晶态晶化;晶态的γ-CuI与Cu2P2O7先后析出,逐渐长大。此材料的分相和晶化行为同电导率反常性的对应,再一次证实了非晶态快离子导体中的相界效应及其普遍意义。 关键词:  相似文献   

7.
崔万秋  阮立坚 《物理学报》1987,36(3):322-331
本文对Li2O-P2O5-V2O5系统非晶态中的几组试样进行了电导率、核磁共振及顺磁共振测试。实验分析表明非晶态的log(σΤ)-1/Τ曲线都是由两个直线段构成。电导率在转变温度以后的“晶化前期”异常增大,这归因于该阶段非晶态结构有序化程度增加所致,利用ESR实验结果对非晶态进行钒离子价态分析表明,该系统非晶态中钒离子仅以V4+和V5+状态存在。固定P< 关键词:  相似文献   

8.
本文研究了非晶态锂离子导体29.6P_2O_5-44.4Li_2O-26.0LiCl和36.3P_2O_5-44.4Li_2O-15.1LiCl-4.2Al_2O_3的阻抗谱,给出了测量盒系统的等效电路,得出了界面阻抗的色散关系。在一定条件下,此界面阻抗过渡到恒相角阻抗。  相似文献   

9.
P2S5/NH4OH处理GaAs(100)表面的电子能谱研究   总被引:3,自引:0,他引:3       下载免费PDF全文
采用俄歇电子能谱(AES)和X射线光电子能谱(XPS)研究了P2S5/NH4OH钝化液处理的GaAs(100)表面的微观特性。AES测量表明,在钝化膜和GaAs衬底之间的界面处无O组分,只有P和S组分。XPS测量分析指出,经过P2S5/NH4OH溶液处理后,GaAs表面处Ga2O3和As2O3关键词:  相似文献   

10.
陈立泉  王连忠  车广灿  王刚 《物理学报》1983,32(9):1170-1176
本文在室温到300℃的温度范围内研究了Li4SiO4-Li3VO4和Li4GeO4-Li4SiO4-Li3VO4体系中的离子导电性,发现γII相固溶体Li3+xV1-xSixO4是好的锂离子导体。所研究的成分中Li3.3V0.7Si0.3O4的离子电导率最高,室温下为1×10-5Ω-1·cm-1,在42—192℃的电导激活能为0.36eV,电子电导率可以忽略,因而这是迄今所发现的最好的锂离子导体之一。粗略确定了Li4GeO4-Li4SiO4-Li3VO4三元系中电导率高的范围,发现在Li3.5V0.5Ge0.5O4中Si部分取代Ge可以使电导率进一步提高,Li3.5V0.5Ge0.4Si0.1O4的室温电导率可达1.3×10-5Ω-1·cm-1,电导激活能为0.40eV。 关键词:  相似文献   

11.
The glass forming regions have been determined in the systems P2O5-A2O-MO (A = Li, Na; M = Cu, Cd), P2O5-Bi2O3-Li2O and P2O5-Bi2O3-ZnO. The largest vitreous domain has been found in the ternary diagram P2O5-Bi2O3-ZnO. The variation of the dielectric constants has been followed inside the glass regions. ε'r increases with increasing amount of alkaline oxides and substantially diminishes with increasing percentage of either CuO or CdO.  相似文献   

12.
崔万秋  陈丹平  陈岩  孙文华 《物理学报》1988,37(11):1741-1751
本文采用红外吸收光谱法、X射线散射法和EXAFS方法研究了LiO-Nb2O-SiO2系统非晶态离子导体的结构,认为Nb5+在非晶结构网络中主要是以[NbO6]形式存在。非晶结构随Nb2O5含量的多少而变化。低Nb2O5含量时,[NbO6]相互间以边相连,并与[SiO4]组成多元环后,形成非晶网络结构。高Nb2O5含量时,非晶网络结构主要是以角顶相连的[NbO6]所组成。根据电导测试结果,讨论了结构与电学性能的关系,认为Li2O含量在0.45左右,Nb2O5,含量在0.3左右组成的非晶材料有最高的电导率。 关键词:  相似文献   

13.
The enthalpies of formation of a series of high and low temperature phases in the ternary oxide system LixV2O5 have been determined by solution calorimetry. Samples of the former, α-Li0.04V2O5, β-Li0.30V2O5, β'-Li0.48V2O5 and γ-LiV2O5, were prepared by solid state reaction at 650°C. The ambient temperature materials Li0.1V2O5(I), Li0.45V2O5(II) and Li1.03V2O5(III) were prepared by n-butyl lithiation in hexane. The thermochemistries of the two classes of material were examined and related to structural features and to the observed behaviour of V2O5 as a battery cathode material in lithium cells.  相似文献   

14.
《Solid State Ionics》1986,21(3):255-261
The electrical conductivity of substituted Li5GaO4 phases was investigated by complex impedance techniques. Substitution by divalent cations to increase the concentration of vacancies in Li5–2xZnxGaO4 did not enhance the ionic conductivity in β-Li5GaO4 -type solid solutions. High Li+ conduction was observed in Li5+xGa1–xMxO4 with M=Mg and Zn in the β-Li5GaO4 structure. The maximum conductivity at 300°C is 4.1 × 10–3 (ω-cm)–1 for Li5.4Ga0.6Zn0.4O4 and 1.3 × 10–3 (ω-cm)–1 for Li5.7Ga0.7Mg 0.3O4. These results are discussed in relation to the structural properties.  相似文献   

15.
A wide variety of solid solutions with a structure related to that of γ Li3PO4 may be prepared. These include materials such as lisicon, Li2+2xZn1-xGeO4 and the title systems, many of which have not been studied previously. Conductivity data are presented for eight systems: Li4GeO4-Li3(P, As, V)O4; Li4TiO4-Li3(As, V)O4; Li4GeO4-Li(Ga, Al)O2; Li4GeO4-Li2CaGeO4 and the results compared with those reported in the literature for Li4SiO4-Li3(P, As, V)O4 systems and lisicon. dc polarisation measurements were made on four of the system and it was found that the electronic transference number is 10?4 or less. The materials with the highest conductivity were found in the systems, Li4 (Ge, Ti) O4-Li3 (As, V)O4 with σ ~ (3 to 4) × 10?5 Ω?1 cm?1 at room temperature. It is noted that the systems with the highest conductivity are generally those with the largest unit cell volume.  相似文献   

16.
分散第二相γ-Al2O3对β-Li2SO4离子导电性的影响   总被引:1,自引:0,他引:1       下载免费PDF全文
本文研究了分散第二相γ-Al2O3对β-Li2SO4离子导电性的影响。β-Li2SO4(γ-Al2O3)的电导率随γ-Al2O3含量的增加而提高,到γ-Al2O3为50mol%时达到极大。当温度为253℃时,β-Li2SO< 关键词:  相似文献   

17.
The principal forms of storage-iron in the lamprey,Geotria australis, are haemosiderin in the nephric fold of the larval animal and ferritin in the liver of the adult. Mössbauer spectroscopy of the larval haemosiderin showed that about half of the iron was in the form of ferrihydrite (5Fe2O3.9H2O) with the remainder being in the form of a non-crystalline iron oxyhydroxide, suggesting two modes of biomineralization. The cores of the adult liver ferritin gave spectral parameters indicating the iron to be predominantly in the form of ferrihydrite with about 10% being in a non-crystalline phase.  相似文献   

18.
Lithium has been chemically and electrochemically incorporated into V2O5 single crystals. The ESR spectra of these room temperature bronzes are characterized by the same g tensor as α-LixV2O5 high temperature bronzes. This suggests that V2O5 acts as a three-dimensional framework host and that lithium is inserted into the channels of the orthorhombic structure. However, Li+ ions are not randomly distributed into the lattice. A clustering of the paramagnetic centers surrounding these ions is observed, giving an exchange narrowed ESR signal. The usual 29 hyperfine line ESR spectrum of high temperature α-LixV2O5 is again observed after heating the crystal above 300°C showing that these new bronzes convert to the previously reported LixV2O5 bronzes.  相似文献   

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