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微波诱导合成固体快离子导电材料 总被引:10,自引:0,他引:10
采用微波法合成了具有快离子传输性质的系列磷锑酸钾化合物K3Sb3P2O14、K2SbPO6、KSbP2O8、KSb2PO8和K5Sb5P2O20以及系列锗锌酸锂固熔体Li2+2xZn1-xGeO4(-0.36〈x〈0.85)。粉末X射线衍射和扫描电镜研究表明,微波合成的样品晶形规整,粒度小且均匀。与传统的高温固相反应相比,微波诱导合成具有反应速度快,易于控制和反应选择性高等特点。在一定温度下微波辐 相似文献
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微波场对固态氧离子导体上的甲烷氧化偶联的影响 总被引:10,自引:0,他引:10
研究了微波场下甲烷在具有δ-Bi2O3结构的固态氧离子导体上氧化偶联反应行为。与常规加热条件下的反应结果相比较,微波辐射下的反应有上特点:(1)在达到相同甲烷转化率时,微波辐照下所需床层温度要远低于常规加热条件下所需床层温度;(2)微波辐照下,甲烷氧化偶联产物中C2烃的选择性普遍较高,在低温区尤为突出。微波场下甲烷偶联产物乙烷、乙烯的再氧化得到一定程度的抑制,致使微波场下的甲烷氧化偶联反应通常有较 相似文献
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Na2ZnSiO4的中温水热合成和离子导电性质研究 总被引:1,自引:0,他引:1
Na_2ZnSiO_4的中温水热合成和离子导电性质研究崔得良,傅戈妍,庞广生,徐秀廷,冯守华,徐如人(吉林大学无机水热合成开放研究实验室,长春,130023)关键词水热合成,硅酸锌钠,离子导体在硅酸盐中,人们已得到了如特种玻璃[1]、微孔晶体[2]“及... 相似文献
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采用线型缩聚法合成了1,2,4,5-均苯四甲酸二酐,4,4'-氨基二苯醚,氨丙基聚二甲硅氧烷和2,5-二氨基苯磺酸四元高分子快离子导体。测定了该共聚物的红外光谱和差动热分析曲线,得到共聚物的玻璃化温度Tg在130℃左右。用交流阻抗谱法测定共聚物薄膜的电导率。四元系的电导率比两个三元系PMDA-ODA-PSX和PMDA-ODA-DABSA分别提高两和一个多数量级。这是因为四元系综合了两个三元系的优点 相似文献
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微波场对固态氧离子导体上的甲烷氧化偶朕的影响 总被引:2,自引:0,他引:2
研究了微波场下甲烷在具有Bi2O3结构的固态氧离子导体上氧化偶联反应行为.与常规加热条件下的反应结果相比较,微波辐照下的反应有如下特点;(1)在达到相同甲烷转化率时,微波辐照下所需床层温度要远低于常规加热条件下所需床层温度;(2)微波辐照下,甲烷氧化偶联产物中C2烃的选择性普遍较高,在低温区尤为突出.微波场下甲烷偶联产物乙烷、乙烯的再氧化得到一定程度的抑制,致使微波场下的甲烷氧化偶联反应通常有较低的烯/烷比. 相似文献
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SrCeO3的微波合成及离子导电性质研究 总被引:2,自引:1,他引:2
SrCeO_3的微波合成及离子导电性质研究徐秀廷,崔得良,冯守华,徐如人(吉林大学无机水热合成开放研究实验室,长春,130023)关键词SrCeO_3,微波合成,离子电导在复合氧化物中,SrCeO3由于具有电子和离子混合导电性质而成为潜在的电极材料。另... 相似文献
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Na1+xAlxZr2—xP3O12的水热合成与表征 总被引:1,自引:0,他引:1
采用水热法合成了系列磷酸盐化合物Na1+xAlxZr2-xP3O12,该系列化合物具有NASICON型三维骨架结构,考查了反应物料配比、晶化时间、晶化时间、晶化温温度等实验条件对产物物相及掺入Al含量对化合物的结构与性能的影响,实验结果表明:在0≤x≤0.33的范围内,可水热合成出Na1+xAlxZr2-xP3O12纯相,而且具有良好的热稳定性,该系列化合物的离子电导率测试结果表明,共电导率与掺入 相似文献
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用溶液电化学方法及固态电极方法研究了Na5YSi4O12(NYS)与K^+和Ag^+的离子交换性质,对离子交换后得到的KNYS和AgNYS样品的结构、密度和离子导电性质进行了表征。与其它离子交换方法相比,上述方法可获得较高的离子交换度,而且元素分析结果与密度测试结果符合良好。 相似文献
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以L iOH.H2O和Mn(CH3COO)2.2H2O作原料,应用微波-固相两段烧结法合成具有L i4Mn5O12结构特征,组成为L i3.22Na0.569Mn5.78O12.0的锂离子电池正极材料.XRD分析表明,在380℃的后处理温度下,微波烧结前处理有利于生成纯L i4Mn5O12尖晶石相.充放电实验表明,在4.5~2.5V电压区间,新制样品的初始放电容量为132 mAh.g-1,100循环的容量衰减率为6.8%;4个月存放样的初始放电容量为122 mAh.g-1,100循环的容量衰减率为17.4%.表现出较好的充放电性能和循环寿命.微波烧结使样品的Mn-O键被加强. 相似文献
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采用一种特殊微波合成法,流变相辅助微波合成法,制备了结晶度好、纯度高的尖晶石相的锂离子电池正极材料LiAl_(0.03)Mn_(1.97)O_4。对其进行了XRD分析和SEM研究,并就结构、形貌与传统固相法制备的LiMn_2O_4、LiAl_(0.03)Mn_(1.97)O_4进行了比较。采用这种漉变相辅助微波合成法制备的LiAl_(0.03)Mn_(1.97)O_4具有优良的电化学性能,电化学性能测试表明,这种材料具有比较高的首次放电容量(115mAh/g)以及良好的可逆性、优异的循环性能,25次循环结束比容量几乎不变,保持在115mAh/g左右,衰减性得到很好的改善。 相似文献
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Synthesis and performance of Li_4Ti_5O_(12) anode materials using the PVP-assisted combustion method
Long-Jiao Chang Shao-Hua Luo Hai-Liang Zhang Xi-Wei Qi Zhi-Yuan Wang Yan-Guo Liu Yu-Chun Zhai 《中国化学快报》2014,25(12):1569-1572
Li_4Ti_5O_(12) was synthesized by a facile gel-combustion method(GCM) with polyvinylpyrrolidone(PVP) as the polymer chelating agent and fuel.The structural and electrochemical properties of the sample were compared with the one prepared by the conventional solid-state reaction(SSR) through X-ray diffraction(XRD),scanning electron microscopy(SEM),cyclic voltammetry(CV),charge-discharge measurements,and electrochemical impedance spectroscopy(EIS),respectively.The sub-microscale Li_4Ti_5O_(12) oxides,with a high phase purity and good stoichiometry,can be obtained by annealing at 800 C.The grain size is smaller than that of the samples that were power prepared by SSR.Lithium-ion batteries with a GCM Li_4Ti_5O_(12) anode exhibit excellent reversible capacities of 167.6,160.7,152.9,and 144.2 mAh/g,at the current densities of 0.5 C,1 C,3 C and 5 C,respectively.The excellent cycling and rate performance can be attributed to the smaller particle size,lower charge-transfer resistance and larger lithium ion diffusion coefficient.It is therefore concluded that GCM Li_4Ti_5O_(12) is a promising candidate for applications in highrate lithium ion batteries. 相似文献
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YAN Guo-Feng LI Guang-She LI Li-Ping FANG Hai-Sheng 《结构化学》2009,28(11):1393-1398
A series of Li4Ti5O12 materials were prepared by three different methods: solvothermal, sol-gel, and solid-state reaction methods. Phase composition, morphology, and particle sizes of the samples were studied by powder X-ray diffraction (XRD) and scanning electron microscopy (SEM). Electrochemical properties of the samples were investigated by charge-discharge tests. It is demonstrated that both sol-gel and solid-state reaction methods provided good control over the chemical composition and microstructure of the active material, in which sol-gel method yielded a fine Li4Ti5O12 spinel having an initial specific capacity of 146 mAh g-1 and low capacity fade during cycling. Comparatively, the solid-state method is simple and promising to prepare Li4Ti5O12 for commercial applications. 相似文献
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《Journal of Energy Chemistry》2020,(1)
As a promising alternative anode material,silicon(Si)presents a larger capacity than the commercial anode to achieve large capacity lithium-ion batteries.However,the application of pure Si as anode is hampered by limitations such as volume expansion,low conductivity and unstable solid electrolyte interphase.To break through these limitations,the core-shell Si@Li_4Ti_5O_(12)nanocomposite,which was prepared via in-situ self-assembly reaction and decompressive boiling fast concentration method,was proposed in this work.This anode combines the advantages of nano-sized Si particle and pure Li_4Ti_5O_(12)(LTO)coating layer,improving the performance of the lithium-ion batteries.The Si@Li_4Ti_5O_(12)anode displays a high initial discharge/charge specific capacity of 1756/1383 m Ah g~(-1)at 500 m A g~(-1)(representing high initial coulombic efficiency of 78.8%),a large rate capability(specific capacity of 620 m Ah g~(-1)at4000 m A g~(-1)),an outstanding cycling stability(reversible specific capacity of 883 m Ah g~(-1)after 150 cycles)and a low volume expansion rate(only 3.3%after 150 cycles).Moreover,the synthesis process shows the merits of efficiency,simplicity,and economy,providing a reliable method to fabricate large capacity Si@Li_4Ti_5O_(12)nanocomposite anode materials for practical lithium-ion batteries. 相似文献
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利用溶剂在层状液晶中的渗透性和层状液晶中溶剂层厚度的限定性,在TritonX-100/C_(10)H_(21)OH/H_2O体系层状液晶中,以饱和Na_2C_2O_4水溶液代替组分水制备水溶性超微粒子材料Na_2C_2O_4,平均粒径约为6nm. 相似文献