N-甲基-N-丁基吡咯烷溴化物和N-甲基-N-乙基吡咯烷溴化物在锌溴液流电池中应用

在锌溴液流电池中,作为溴络合剂在电解液中使用的季铵盐对电池性能及安全性具有重要作用.本文利用循环伏安法及线性扫描伏安法研究了N-甲基-N-丁基吡咯烷溴化物（N-methyl-N-butyl-pyrrolidinium bromide,MBP）和N-甲基-N-乙基吡咯烷溴化物（N-methyl-N-ethyl-pyrrolidinium bromide,MEP）分别加入到电解液后对电极反应的影响,通过交流阻抗（EIS）的方式测量了不同组成及浓度下的电解液电导率变化,测试了不同电解液对电池充放电性能的影响及溴络合能力,结果表明加入MBP的电解液具有更好的溴络合能力和电池性能.     

N-甲基-N-丁基吡咯烷溴化物和N-甲基-N-乙基吡咯烷溴化物在锌溴液流电池中的应用

在锌溴液流电池中,作为溴络合剂在电解液中使用的季铵盐对电池性能及安全性具有重要作用.本文利用循环伏安法及线性扫描伏安法研究了N-甲基-N-丁基吡咯烷溴化物和N-甲基-N-乙基吡咯烷溴化物加入到电解液后对电极反应的影响,利用交流阻抗测量了不同组成及浓度下的电解液电导率变化,测试了不同电解液对电池充放电性能的影响及溴络合能力,结果表明加入MBP的电解液具有更好的溴络合能力和电池性能.     

锌电极电化学行为Ⅵ.锌粉在碱性电解液中的电化学腐蚀

锌电极是广泛使用于一次和二次电池中的阳极材料. 在二次电池中主要是以锌粉作为电极材料. 长期以来,由于锌粉电极在充放电过程中发生形变和枝晶生长等^[1],致使它组成的二 次电池循环寿命差. 为了研究锌粉在碱性电解液中的腐蚀行为,人们通常是使用锌盘电极来模拟锌粉的情况^[2]. 但是锌盘与锌粉不同. 为此,我们采用电解沉积锌粉于锌盘电极上,制成 粉状电极研究锌粉在碱性溶液中的腐蚀行为及一些非离子型有机缓蚀剂对锌粉的缓蚀作用     

芘对聚苯胺锂硫电池低温性能的影响机制研究

提出在电解液中加入电荷转移中间体改善锂硫电池低温性能的思路,在电解液中添加芘作为电荷转移中间体,加速低温下聚苯胺锂硫电池电化学反应的平衡过程.循环伏安研究证明,芘在锂硫电池放电过程中的高压平台附近具有电化学活性,并通过X射线光电子能谱证实芘的引入能够使锂硫电池在低温下提高多硫化物平衡速率,延长第一平台,生成更多长链多硫化锂.对同样电极材料组成的聚苯胺/硫复合正极材料构成的锂硫电池,当在电解液中加入0.1 mol/L的芘时,相比于不含芘的锂硫电池,其第50次充放电循环下容量在0oC时能够提升22.8%,而在-15oC时能提升25.1%.     

MH—Ni电池低温性能的研究

从合金组成及电解液组份研究了ＭＨ－Ｎｉ电池的低温性能，确定了适宜的合金组成和电解液组成。     

环亚硫酸甘油酯衍生物作为电解液添加剂对锂离子电池电化学性能的影响

在亚硫酸酯基团的基础上引入苯环,设计并合成了3种环亚硫酸甘油酯衍生物[双(1,2-环亚硫酸甘油酯)对苯二甲酸酯、三(1,2-环亚硫酸甘油酯)均苯三甲酸酯和四(1,2-环亚硫酸甘油酯)均苯四甲酸酯],通过倍率充放电、恒流充放电、交流阻抗和扫描电子显微镜等测试研究了这些添加剂对锂离子电池性能的影响.结果表明,与空白电解液相比,加入三(1,2-环亚硫酸甘油酯)均苯三甲酸酯的电解液球化石墨电极表面可形成一层致密而稳定的固体电解质界面(SEI)膜,从而优化电极-电解液的界面性能,改善电池的倍率性能和循环性能,且在循环80周后电池阻抗增加较小;而双(1,2-环亚硫酸甘油酯)对苯二甲酸酯和四(1,2-环亚硫酸甘油酯)均苯四甲酸酯的加入不会明显改善电池的循环性能.研究结果表明苯环上亚硫酸甘油酯基团的数目对其性能影响较大.     

含稀土钇电极材料的声化学制备及电化学性能

通过超声浸渍法以不同浓度的Y(NO3)3溶液成功地制得几种声化学改性锌粉, 以期改善碱性电池锌电极的电化学性能. 利用扫描电镜(SEM)、X射线衍射(XRD)及电化学测试等方法考察了改性锌粉上Y(OH)3/Y2O3的形成及相应锌电极的耐腐蚀和循环性能. 结果表明, Y(NO3)3浓度为0.036 mol·L-1时, 声化学改性锌粉表面均匀分布着颗粒状的Y(OH)3/Y2O3, 且这些钇化合物优先生长在锌粉表面的缺陷位置, 阻挡了电化学过程中锌酸根离子向碱性电解液中的溶解与扩散, 使得相应锌电极的缓蚀效率达79.6%, 且20次循环伏安曲线的阴、阳极峰电位差比空白样减小了285 mV. 将这种改性锌粉和空白锌粉组装成模拟锌银电池, 在250 mA·cm-2的高放电电流密度下测试发现, 声化学改性锌粉的锌电极从1次到30次循环的放电容量损失仅为62.7 mAh·g-1; 且放电容量在50周期时达到322.6 mAh·g-1, 说明声化学改性锌粉可明显提高电极的放电容量和循环寿命.     

三氟乙氧基磷酸酯的合成与性能研究

为提高锂离子电池安全性，本文制备了锂离子电池阻燃添加剂-三氟乙氧基磷酸酯（TFP）。通过红外（IR）光谱法鉴定了产物结构；讨论了反应时间、反应物浓度比与产率的关系；以及TFP的加入对1mol／L LiPFoEC／EMC／DMC（1：1：1Vol．）电解液的可燃性、分解电压和离子电导率的影响。结果表明：反应时间、反应物浓度比对TFP产率影响较为明显，当催化剂为15mol．％（相对于三氯氧磷），反应时间6h，三氟乙醇与三氯氧磷摩尔比为6：1时，TFP的产率可以达到94．00％；添加TFP对电解液阻燃效果显著，对电解液的分解电压无不利影响，电解液电导率会有所下降，对Li／LiCoO2电池的比容量影响不大。     

氟代溶剂在锂金属电池中的应用

近年来，锂金属电池由于具有较高的能量密度而成为储能领域的研究热点。电解液作为锂金属电池的“血液”发挥着至关重要的作用。在传统锂离子电池电解液中，锂金属负极与电解液之间的界面副反应严重并伴随着锂枝晶生长，从而导致安全隐患以及循环寿命缩短等问题。在解决锂金属负极问题上，电解液调控策略具有易操作性和有效性，因而在推动锂金属电池发展方面具有举足轻重的地位。氟代电解液是目前重要的研究方向，氟代电解液在循环过程中能够在电极表面形成富含LiF的固体电解质界面膜(SEI)；该界面膜不仅可以有效抑制负极锂枝晶的形成，并且在正极方面能够大幅提高电解液的氧化稳定性，从而提升高电压正极的适配性和锂金属电池的循环稳定性。氟代电解液中氟代溶剂/氟代锂盐的分子结构对电解液的溶剂化结构有重要影响。当氟代溶剂分子中氟原子的位置与数量不同时，氟代溶剂的物理化学性质也会随之发生变化，进而改变了电解液与电极的界面反应性。因此，氟代溶剂能够起到调制SEI膜成分和结构的作用，是决定电池性能的关键因素。本文总结了应用于锂金属电池的主要氟代溶剂，尤其是近几年来发展的新型氟代溶剂；着重介绍了高度氟代的溶剂分子作为局域超浓电解液的稀释剂，以及对溶剂进行精准分子设计得到的部分氟代溶剂等。此外，本文还分析探讨了氟代溶剂分子与电池性能之间的构效关系，展望了构建新型氟代溶剂分子的策略，希望能对电解液溶剂分子的结构设计以及构效关系的评估有一定的启发意义。     

新型锂离子电池电解液添加剂的合成与应用

设计并合成了一系列基于苯环和环状碳酸酯的有机分子双(2,3-环碳酸甘油酯)对苯二甲酸酯、三(2,3-环碳酸甘油酯)均苯三甲酸酯和四(2,3-环碳酸甘油酯)均苯四甲酸酯,采用倍率测试、恒流充放电测试、交流阻抗测试和扫描电子显微镜测试等手段研究了这些添加剂对锂离子电池性能的影响.通过对循环20周前后球化石墨电极形貌的对比,发现含均苯四甲酸酯和均苯三甲酸酯的电解液球化石墨电极表面相对于空白电解液可形成一层致密而稳定的固体电解质中间相膜(SEI),从而优化电极-电解液的界面性能,且电池电阻增加较小;在测试电池的倍率性能时发现,均苯四甲酸酯的加入可以改善电池的倍率性能,而对苯二甲酸酯的加入则未能改善电池的循环性能.     

Study on corrosion resistance of electroplating zinc–nickel alloy coatings

Electrodeposited zinc–nickel alloy coatings have been widely adopted for surface treatment of automobile body steel sheet for high corrosion resistance. The corrosion behavior of the coatings has been related with the components of nickel, and the zinc–nickel alloy passive coatings have much higher corrosion resistance than that of zinc–nickel alloy coatings. In the present paper, the corrosion resistance behavior of the zinc–nickel alloy coatings obtained by new process and formulation has been studied by means of the electrochemistry test and neutral salt spray test. And it is discovered that the properties of corrosion resistance of zinc–nickel alloy passive coatings were better than that of zinc passive coatings, Cadmium passive coatings and alloys of electrodeposited cadmium–titanium. The components of corrosion productions, in terms of X‐ray diffraction (XRD), are mainly ZnO, ZnCl₂ · 4Zn(OH)₂ and small quantity of 2ZnCO₃· 3Zn(OH)₂. The component of zinc–nickel alloy coatings has been investigated with Glow Discharge Optical Emission Spectrometry (GDA‐750). And it is found that as the thickness of zinc–nickel alloy coatings increases, the component of zinc increases from beginning to end, but the peak value of nickel appears and an enrichment of nickel in the coatings comes into being. Because the electrodeposited zinc–nickel alloy coatings exhibit different alloy phases as a function of their alloy composition, in this paper, the crystal structure changing with the different component of nickel has been studied in terms of XRD. The result shows that electrodeposited zinc–nickel alloy has different phases: α‐phase, a solid solution of zinc in nickel with an equilibrium solubility of about more than 79% nickel; γ‐phase, an intermediate phase with a composition Ni₅Zn₂₁; η‐phase, a solid solution of nickel in zinc with less than 5% nickel; and δ‐phase (Ni₃Zn₂₂) appeared from η‐phase to α‐phase with increasing content of nickel. Copyright © 2009 John Wiley & Sons, Ltd.     

Electrodeposition and characterization of Zn–Sn alloy coatings from a deep eutectic solvent based on choline chloride for corrosion protection

With the aim of obtaining high corrosion resistant Zn–Sn alloy coatings from an ionic liquid, the effects of electrodeposition potential and electrolyte composition on the electrodeposition behavior, film composition, morphology and corrosion performance were investigated. Cyclic voltammograms indicate that Zn and Sn were co‐deposited at distinct reduction potentials as pure Zn and Sn elements. In addition, the phase composition analysis also showed that the obtained Zn–Sn alloy deposits (8 wt.%–45 wt.% Zn) consist of a two‐phase mechanical mixture of small aggregates of Zn and Sn metals. The Zn content of the alloy significantly increases as the electrodeposition potential and electrolyte Zn (II)/Sn (II) ratio increase. The corrosion performance study of the obtained Zn–Sn coatings showed that they have a passivation behavior and their corrosion resistance increases as the alloy‐Sn content increases. To improve their morphological properties, ethylene diamine tetraacetic acid additive was introduced into the electrolyte and greatly improved the morphology and corrosion resistance of the deposits. For the first time, it was shown that high corrosion resistance Zn–Sn coatings can be obtained from ionic liquids. Copyright © 2014 John Wiley & Sons, Ltd.     

AZ91D镁合金上钼改性锌系磷化膜的制备、 结构及性能

采用在磷化液中添加钼酸钠及腐蚀抑制剂的方法, 在AZ91D 镁合金表面上制备了均匀细致的锌系复合磷化膜. 用XRD对膜层的化学组成及结构进行了表征,用SEM和EDS对膜层的形貌和组分含量进行分析. 结果表明, 磷化膜主要由Zn3(PO4)2·4H2O和单质Zn组成. 在磷化液中加入钼酸钠使磷化膜组织更加细致而且无裂纹. 磷化液中的钼酸钠含量为1.5 g/L时, 磷化膜的结晶最致密, 单质锌的含量最高, 耐蚀性最好. 还提出了一种快速测量镁合金表面膜层耐蚀性的试验方法, 同时对镁合金上的磷化反应的机理进行了探讨.     

Surface analysis and corrosion resistance of new nickel base thin film alloys

Electroless Zn–Ni–P thin films were deposited on low carbon steel from an alkaline non‐cyanide aqueous electrolyte. The newly developed ternary alloys structure and microstructure investigations were carried out via X‐ray diffraction and SEM. Chemical composition of the coatings was investigated via energy dispersive spectroscopy. Polarization tests were used to study the corrosion properties of the coatings in a 3.5 wt.% NaCl solution. The results confirmed the high corrosion resistance of Zn–Ni–P alloy plated steel sheet. The surface analysis of the thin film samples before and after corrosion was performed by XPS. The incorporation of Zn in Ni–P thin film is proven for all initial samples to be as a mixture of zinc and zinc oxide, while nickel exists in +2 and +3 oxidized states. A passive film of a mixture of oxide and hydroxide of zinc and nickel forms on the surface and prevents the Zn–Ni–P thin films from corrosion. Copyright © 2014 John Wiley & Sons, Ltd.     

六种祛风湿中成药中微量元素含量的测定

中药功效与微量元素之间的关系 ,已被越来越多的学者研究证实[1～ 3] ,但对祛风湿中成药中微量元素的分析未见报道。现代医学中 ,风湿病是指与免疫代谢、感染、遗传、退行性变有关的骨、关节、肌肉疼痛为主的疾患 ,其范围相当广泛 ,为临床常见病[4] 。本文通过对风湿马钱片等 6种祛风湿中成药中Ｚｎ、Ｆｅ、Ｃｕ、Ｍｎ、Ｓｅ、Ｐｂ、Ｈｇ等 7种微量元素含量的测定 ,为进一步研究相关微量元素的存在形态、探讨药理机制、提高药效和降低毒副作用提供参考。1　实验1 1　仪器与试剂ＷＦＸ ⅠＣ型原子吸收分光光度计 (北京第二分析仪器厂 ) ,Ｗ…     

The determination of zinc,cadmium, lead and copper in a single sea-water sample by differential pulse anodic stripping voltammetry

A comparative study is described of the anodic stripping voltammetry of sea water at its natural pH and at acetate-buffered pH, with a mercury film electrode. The reproducibility of the oxidation current peaks for copper and lead is improved and the electrode memory effect decreases, when the sample is acetate-buffered (pH 5.8). Determinations of zinc at the natural pH of sea water are inaccurate, because of the formation of Zn—Cu and Zn—Ni intermetallic compounds in the mercury film. The formation of such compounds can be prevented by the addition of gallium ions to acetate-buffered samples. A procedure for the determination of Cu, Pb, Cd and Zn in sea water is described.     

A Self-Deoxidizing Electrolyte Additive Enables Highly Stable Aqueous Zinc Batteries

In aqueous zinc (Zn) batteries, the Zn anode suffers from severe corrosion reactions and consequent dendrite growth troubles that cause fast performance decay. Herein, we uncover the corrosion mechanism and confirm that the dissolved oxygen (DO) other than the reputed proton is a principal origin of Zn corrosion and by-product precipitates, especially during the initial battery resting period. In a break from common physical deoxygenation methods, we propose a chemical self-deoxygenation strategy to tackle the DO-induced hazards. As a proof of concept, sodium anthraquinone-2-sulfonate (AQS) is introduced to aqueous electrolytes as a self-deoxidizing additive. As a result, the Zn anode sustains a long-term cycling of 2500 h at 0.5 mA cm⁻² and over 1100 h at 5 mA cm⁻² together with a high Coulombic efficiency up to 99.6 %. The full cells also show a high capacity retention of 92 % after 500 cycles. Our findings provide a renewed understanding of Zn corrosion in aqueous electrolytes and also a practical solution towards industrializing aqueous Zn batteries.     

稀土氧化物对二次锌电极性能的影响

应用阴极极化法在锌电极上覆盖一层稀土氢氧化物膜La(OH)3或Ce(OH)3,并用循环伏安、动电位极化、定电位阴极极化实验研究其电化学性能.结果表明,La(OH)3或Ce(OH)3膜能抑制锌酸根离子的迁移,提高析氢过电位,降低腐蚀电流密度并能抑制枝晶生长.SEM观测显示,稀土氧化物La2O3或CeO2改变了锌沉积形态,进而提高了锌酸钙电极的充放电循环性能.     

三维多孔Sn-Zn合金电极助力Zn的均匀沉积/剥离

通过在化学镀构建的三维多孔铜上电沉积锡-锌(Sn-Zn)合金, 构筑了孔径为5 μm左右的三维多孔 Sn-Zn合金电极(3D Sn-Zn), 对其形貌、 结构和性能进行了表征和测定. 结果表明, 该电极拥有高稳定性和适宜孔径的三维多孔结构, 可降低局部电流密度, 提供均匀的电场分布, 缓解了由于锌的不均匀生长而造成的粗大枝晶; 合金镀层中的Sn元素不仅可以增大析氢过电位, 增强电极的防腐蚀性能, 还可降低锌的形核势垒, 为锌的沉积提供丰富的形核位点, 促进锌在电极表面的均匀沉积, 减少枝晶的形成. 采用3D Sn-Zn电极组装的对称电池, 在0.5 mA/cm² 下可稳定循环超过1200 h, 电压滞后仅为21.3 mV; 而采用锌片(2D Zn)组装的对称电池电压滞后达到了99.2 mV, 且在循环300 h后开始出现剧烈的电压波动. 使用3D Sn-Zn电极组装的全电池在 1.8 A/g电流密度下可稳定循环2000次.     

碱性溶液中锌电极缓蚀的研究

研究了硝酸铅（Pb(NO3)2）和十二烷基苯磺酸钠（SDBS）及二者组成的复合添加剂对在3mol•L-1 KOH溶液中锌电极电化学行为的影响, 结果表明:两种添加剂均具有一定的缓蚀作用,而其复合添加剂的协同效应、缓蚀效果最佳.