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ICP-AES法测定锌阳极中的铝、镉、铁、铜、铅 总被引:2,自引:0,他引:2
通过分析高频功率、雾化压力、辅助气流量和泵速等试验条件,建立了ICP-AES法测定锌阳极中铝、镉、铁、铜、铅的方法。用该方法测定锌阳极中的铝、镉、铁、铜、铅,其RSD分别为0.17%、0.63%、2.7%、5.2%、2.5%,回收率分别为99.3%-101.2%,99.3%-100.3%、97.1%-102.2%、97.8%-102.9%。对锌阳极试样进行测定,该方法的测定结果与GB4951-85方法的测定结果基本一致。 相似文献
23.
E.?V.?TsipisEmail author V.?V.?Kharton I.?A.?Bashmakov E.?N.?Naumovich J.?R.?Frade 《Journal of Solid State Electrochemistry》2004,8(9):674-680
Developments of intermediate-temperature solid oxide fuel cells (IT SOFCs) require novel anode materials with a high electrochemical activity at 800–1070 K. The polarization of cermet anodes, made of nickel, ceria and yttria-stabilized zirconia (YSZ) and applied onto a YSZ solid electrolyte, can be significantly reduced by catalytically active ceria additions, the relative role of which increases with decreasing temperature. Further improvement is observed when using Ce0.8Gd0.2O2–
(CGO) having a high oxygen ionic conductivity instead of undoped ceria, owing to enlargement of the electrochemical reaction zone. Nanocrystalline CGO powders with grain sizes of 8–35 nm were thus synthesized via the cellulose-precursor technique and introduced into Ni–CGO–YSZ cermets, and tested in contact with a (La0.9Sr0.1)0.98Ga0.8Mg0.2O3–
(LSGM) electrolyte at 873–1073 K. The results showed that the anode performance can be enhanced by additional surface activation, in particular by impregnation with a Ce-containing solution, and also by incorporation of YSZ, which probably acts as a cermet-stabilizing component. The overpotential of the surface-modified Ni–CGO (25 wt%–75 wt%) anode in a 10% H2/90% N2 atmosphere was approximately 110 mV at 1073 K with a current density of 200 mA/cm2.Presented at the OSSEP Workshop Ionic and Mixed Conductors: Methods and Processes, Aveiro, Portugal, 10–12 April 2003 相似文献
24.
Tsuyoshi Nakajima 《Journal of fluorine chemistry》2007,128(4):277-284
Recent results on the surface modification of petroleum cokes and their electrochemical properties as anodes of secondary lithium batteries are summarized. The surface of petroleum coke and those heat-treated at 1860-2800 °C were fluorinated by elemental fluorine (F2), chlorine trifluoride (ClF3) and nitrogen trifluoride (NF3). No surface fluorine was found except only one sample when ClF3 and NF3 were used as fluorinating agents while surface region of petroleum coke was fluorinated when F2 was used. Transmission electron microscopic (TEM) observation revealed that closed edge of graphitized petroleum coke was destroyed and opened by surface fluorination. Raman spectra showed that surface fluorination increased the surface disorder of petroleum cokes. Main effect of surface fluorination with F2 is the increase in the first coulombic efficiencies of petroleum cokes graphitized at 2300-2800 °C by 12.1-18.2% at 60 mA/g and by 13.3-25.8% at 150 mA/g in 1 mol/dm3 LiClO4-ethylene carbonate (EC)/diethyl carbonate (DEC) (1:1, v/v). On the other hand, main effect of the fluorination with ClF3 and NF3 is the increase in the first discharge capacities of graphitized petroleum cokes by ∼63 mAh/g (∼29.5%) at 150 mA/g in 1 mol/dm3 LiClO4-EC/DEC. 相似文献
25.
锂离子二次电池碳负极材料的改性 总被引:5,自引:1,他引:5
作为锂离子二次电池的碳负极材料,其改性方面的研究内容主要有:引入非金属元素,引入金属元素,处理表面及其它方面。纺入的非金属元素有硼,硅,氮,磷和硫。引入的金属元素有钾,铝,镓和钒,镍,钴,铜,铁等过渡金属元素。表面处理的方法包括氧化,形成表面层等。 相似文献
26.
Yakhvarov D. G. Budnikova Yu. H. Tazeev D. I. Sinyashin O. G. 《Russian Chemical Bulletin》2002,51(11):2059-2064
The material of the sacrificial anode has a substantial effect on the nature and yield of the target products of electrochemical phosphorylation of organic halides by white phosphorus in the presence of the nickel complexes with 2,2"-bipyridine. The use of the zinc anode results in the products with tricoordinated phosphorus, viz., triorganylphosphines, the reaction on the aluminum anode affords triorganylphosphine oxides, and the presence of Mg2+ ions in the reaction mixture provides the transformation of white phosphorus into cyclic phosphines (PhP)5. 相似文献
27.
28.
Natural graphite samples with average particle sizes of 5, 10 and 15 μm (NG5 μm, NG10 μm and NG15 μm, respectively) were fluorinated by ClF3 (3 × 104 Pa) at 200 and 300 °C for 2 min. X-ray photoelectron spectra of surface-fluorinated samples showed that surface fluorine concentration increased with increase in the particle size of graphite and reaction temperature. Small amounts of chlorine were also detected in all the fluorinated samples. Raman spectra of original and surface-fluorinated samples indicated that the surface disordering was increased for NG10 μm and NG15 μm. Surface areas were decreased by the fluorination for NG5 μm and NG10 μm but unchanged for NG15 μm. The mesopores with diameter of 1.5-2 nm increased while those of 2-3 nm decreased for all the samples. First coulombic efficiencies for NG10 μm and NG15 μm were highly increased by surface fluorination in 1 mol/dm3 LiClO4-EC/DEC/PC (EC: ethylene carbonate, DEC: diethyl carbonate, PC: propylene carbonate) solution. 相似文献
29.
PbO2阳极在硫酸溶液中的析氧失活行为 总被引:1,自引:0,他引:1
采用热分解鄄电镀法制备了以Sb 掺杂SnO2(Sb-SnO2)为底层的Ti 基PbO2阳极(Ti/PbO2). 采用加速电解寿命测试、电化学阻抗谱、XRD、SEM-EDX 等技术, 研究了Ti/PbO2阳极在硫酸溶液中的电解失效行为和机制.结果表明,在新制备的PbO2镀层中, 由于氧空位的存在, PbO2镀层的内应力表现为拉应力, 随着电解的进行, 阳极表面生成的活性氧原子在向基底扩散的过程中, 将Pb3+态氧化为Pb4+态, 逐渐占据镀层内作为自由电子施主的氧空位, 这不仅导致镀层的导电性能下降, 同时使镀层的应力逐渐由拉应力转变为压应力, 镀层性质逐渐劣化. 这一过程基本结束时,活性氧原子才大量扩散至Ti基底导致基底的钝化, 在Ti 基底和镀层界面出现显著的界面应力, 在界面应力和镀层内压应力的共同作用下, 阳极出现鼓泡、脱落, 迅速进入失活阶段. 相似文献
30.
Numerous carbonaceous materials have been studied as anodes of lithium ion batteries during the past several years[1 ̄4].Graphite was favored for battery applications because it exhibits a high specific capac- ity, low working potential close to that of l… 相似文献