Proton-Coupled Electron Transfer Aided Thermoelectric Energy Conversion and Storage

Low-grade heat is ubiquitous in the environment and its thermoelectric conversion by the ionic conductors remains a challenge because of the low efficiency and poor sustainability. Here we demonstrate that the thermoelectric performances can be boosted by combining the Soret effect of protons and proton-coupled electron transfer (PCET) reaction of benzoquinone and hydroquinone in hydrogels. An overall enhancement of thermopower (25.9 mV K⁻¹), power factor (5 mW m⁻¹ K⁻²), figure of merit (>2.4) and continuity of power output is achieved. Moreover, an energy-storage function can be achieved by the redox couple, and a retained power output of 27.7 %, or 14 mW m⁻² for more than 3 hours is obtained by the re-balance of PCET reactants in the hydrogel after the removal of the temperature gradient.     

一种新型有机硅离子液体电解液在超级电容中的应用

设计合成了一种新型有机硅室温离子液体(SiN1IL), 并对其化学结构和电化学窗口进行表征, 通过与具有高介电常数的丙烯碳酸酯(PC)/低粘度的乙腈(AN)匹配组成电解液, 其离子电导率达到商业实际应用的要求(19.6 mS·cm^-1). 对以活性炭(AC)为对称电极的超级电容器的电化学性能测试表明, SiN1IL 基电解液与活性炭有很好的界面相容性, 其高倍率充放电、阻抗性能优于商用四乙基四氟硼酸铵(Et₄NBF₄)/PC 电解液, 在电流密度为1000 mA·g^-1的条件下, 工作电压为2.7 V, 其比电容为108 F·g^-1.     

离子液体在TiO2纳晶染料敏化太阳能电池中的应用

离子液体以其高稳定性、高电导率等特有的优点,成为众多领域中研究的热点。本文简单综述了离子液体的概念、结构及其在TiO2纳晶染料敏化电池的固、液态电解质中的应用,并对其应用前景进行了展望。     

染料敏化纳米薄膜太阳电池中离子液体基电解质的研究进展

综述了离子液体基电解质在染料敏化纳米薄膜太阳电池中的研究及应用进展，详细论述了多种离子液体基电解质系统对染料敏化纳米薄膜太阳电池性能的影响，并比较了这些系统的优缺点. 根据胶凝剂的不同分别论述了离子液体基电解质的固化及其对电池性能的影响. 评述了离子液体基电解质在大面积电池中的应用，并对离子液体基电解质未来发展方向进行了展望.     

天然石墨阳极在室温离子液体电解液中的电化学性质

对比研究了天然石墨在室温离子液体和有机电解液中的嵌脱锂性质, 探讨了添加剂提高天然石墨在离子液体电解液中电化学性质的微观机制.     

Amide-Based Ionic Liquid Electrolytes for Alkali-Metal-Ion Rechargeable Batteries

Ionic liquids (ILs) have a wide variety of applications in energy storage and material production. ILs are composed of only cations and anions, without any molecular solvents, and are generally known as “designer liquids (solvents)” because their physicochemical properties can be tuned by the combination of ionic species. In recent several decades, research and development activities of rechargeable batteries have garnered considerable attention because certain groups of ILs exhibit high electrochemical stability and moderate ionic conductivity, rendering them suitable for application in high-voltage batteries. ILs with amide anions are representative electrolytes and are extensively researched by many research groups, including our group. This paper focuses on amide-based ILs as electrolytes for alkali-metal-ion rechargeable batteries, introducing their history, characteristics, and existing challenges to be addressed.     

Sodium Ion Batteries using Ionic Liquids as Electrolytes

Sodium ion batteries have been developed using ionic liquids as electrolytes. Sodium is superior to lithium as a raw material for mass production of large‐scale batteries for energy storage due to its abundance and even distribution across the earth. Ionic liquids are non‐volatile and non‐flammable, which improved the safety of the batteries remarkably. In addition, operation temperatures were extended to higher values, improving the performance of the batteries by facilitating the reaction at the electrode and mass transfer. Binary systems of sodium and quaternary ammonium salts, such as 1‐ethyl‐3‐methylimidazolium and N‐methyl‐N‐propylpyrrolidinium bis(fluorosulfonyl)amide, were employed as electrolytes for sodium ion batteries. A series of positive and negative electrode materials were examined to be combined with these ionic liquid electrolytes. A 27 Ah full cell was fabricated employing sodium chromite (NaCrO₂) and hard carbon as positive and negative electrode materials, respectively. The gravimetric energy density obtained for the battery was 75 Wh kg^?1 and its volumetric energy density was 125 Wh L^?1. The capacity retention after 500 cycles was 87 %. Further improvement of the cell performance and energy density is expected on development of suitable electrode materials and optimization of the cell design.     

丙氨酸离子液体[C4mim][Ala]的热化学性质

在298.15 K下利用恒温环境溶解热量计测定了一系列含有已知微量水的1-丁基-3-甲基咪唑丙氨酸盐([C₄mim][Ala])离子液体(IL)不同浓度样品的摩尔溶解焓. 借助Debye-Hückel极限项, 用外推法确定了不同含水量的[C₄mim][Ala]样品的标准摩尔溶解焓[Δ_sH_m⁰(wc)]. 随着样品中水含量的增加, Δ_sH_m⁰(wc)的绝对值下降, 将Δ_sH_m⁰(wc)对含水量作图得到很好的直线, 其截距Δ_sH_m⁰(pure IL)=-60.74 kJ/mol, 可看作是不含水的[C₄mim][Ala]标准摩尔溶解焓的估算值. 利用精密氧弹热量计测定了[C₄mim][Ala]的燃烧热, 计算得到其标准摩尔生成焓Δ_fH_m⁰=(-675±11) kJ/mol.     

阴离子为羧酸根和芳环共轭的离子液体在染料敏化太阳能电池中的应用

提出了利用p-π共轭效应设计离子液体的方法, p-π共轭效应可以有效分散阴离子的负电荷, 降低离子液体中阴阳离子之间的库仑引力, 以得到低粘度的离子液体. 所设计的离子液体为1-乙基-3-甲基咪唑苯甲酸(EMIB)和1-乙基-3-甲基咪唑异烟酸(EMIIN) (它们的阴离子中羧酸根和芳环为p-π共轭结构), 这两种离子液体都达到了较低的粘度(EMIB为42 mPa·s, EMIIN为27 mPa·s). 进一步将这两种离子液体做成电解质, 应用在染料敏化太阳能电池中, 通过优化电解质的组成, EMIB基电解质达到了1.43 mS·cm^-1的电导率和1.45×10^-7cm²·s^-1的I₃^?的扩散系数, 而EMIIN基电解质的电导率和I₃^?扩散系数分别为1.63 mS·cm^-1和2.01×10^-7 cm²·s^-1,后者电导性能的提高主要和EMIIN粘度较低有关系. 进一步将这两种电解质组装成电池, 在300 W·m^-2的光强下测得EMIB基电池和EMIIN基电池的效率分别为2.85%和4.30%.     

过渡金属离子液体[C2mim][FeCl4]的溶解热

在干燥氩气氛下, 用等摩尔的高纯无水FeCl3和氯化1-甲基-3-乙基咪唑([C2mim][Cl])直接搅拌混合, 制备棕色透明的含过渡金属铁的离子液体[C2mim][FeCl4]. 在298.15 K下, 利用具有恒温环境的溶解反应热量计测定了这种离子液体的摩尔溶解焓(ΔsHm). 针对[C2mim][FeCl4]溶解于水后即分解的特点, 在Pitzer电解质溶液理论基础上, 提出了确定这种离子液体标准摩尔溶解焓的新方法, 得到了[C2mim][FeCl4]的标准摩尔溶解焓(ΔsH 0—m=-76.6 kJ/mol), 以及Pitzer焓参数组合: β(0)LFe,Cl+β(0)L[C2mim], Cl+ΦLFe,[C2mim]=0.072209和β(1)LFe,Cl+β(1)L[C2mim], Cl=0.15527. 借助热力学循环和Glasser离子液体晶格能理论, 用Fe3+, Cl-和[C2mim]+的离子水化焓数据以及[C2mim][FeCl4]标准摩尔溶解焓, 估算得到了配离子[FeCl4]-(g)解离成Fe3+(g)和4Cl-(g)的解离焓为5659 kJ/mol. 这个结果揭示了离子液体[C2mim][FeCl4]的标准摩尔溶解焓绝对值并不很大的原因, 即很大的离子水化焓被很大的[FeCl4]-(g)的解离焓相互抵消.     

二茂铁在几种离子液体中的迁移行为

采用循环伏安法研究了二茂铁(Fc)在几种离子液体中的迁移行为. 计算了Fc在各离子液体中的扩散系数和粘度系数,探讨了离子液体粘度与离子液体结构之间的关系. 实验结果表明, 离子液体的粘度随阳离子取代基碳链长度的增加而增加, 随阴离子对称性的增加而增加.     

功能化的离子液体在电化学中的应用

离子液体独特的全离子结构无疑会导致良好的导电性,成为有潜力的绿色电化学材料。功能化是实现离子液体专一性的重要手段。本文综述了近几年功能化的离子液体在电化学研究中的进展,内容包括阴离子功能化、阳离子功能化和离子液体固相化。作者还对离子液体结构与离子电导率、电势窗口、稳定性和溶解能力的关系提出了一些看法。     

Ionic Liquid Solvent Based on Cyclic Guanidinium Cation for Nucleophilic Displacement Reactions

The nucleophilic displacement reaction of n-bromooctane and potassium iodide in ionic liquid based on cyclic guanidinium cation(2) was investigated. The kinetic reasuh shows that the rate of the reaction is enhanced in ionic liquid (2). The same reaction in [bmim][PF6] (1)(where bmim=1-butyl-3-methylimidazolium) was also studied. It was found that as a reaction medium ionic liquid (2) is better than (1) for nucelophilic displacement reactions.     

基于离子液体的绿色电子器件

基于离子液体的绿色液体电子器件可回收性强,且具备柔性、自修复性、可重塑与可重构性等性能,拓宽了液体电子器件的应用范围,为绿色环保的多功能电子器件的开发提供了新途径.本文围绕离子液体基的电子器件进行了总结,并阐述了该类器件广阔的应用前景.     

Study of Anion Effects on Separation Phenomenon for the Vinyloctylimidazolium Based Ionic Liquid Polymer Stationary Phases in GC

Poly-vinyloctylimidazolium ionic liquid polymers with different counter ions (bromide, hexafluorophosphate and bis-trifluoromethanesulfonylimide) were directly coated in capillary fused silica tubing as the stationary phases for gas chromatography. The anion effects on the polymers were examined and discussed. The results suggest that the poly-vinyloctylimidazolium, bis-trifluoromethanesulfonylimide capillary column has the highest thermal stability and separation efficiency. Column-to-column reproducibility was also studied. The results indicate that anions significantly influence ionic liquid polymers which give them potential to extend the range of options for the stationary phases in gas chromatography.     

高温高分子快离子导体PMDA—ODA—PSX—DABSA的合成和性能

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     

Ionic radii in aqueous solutions

The aqueous ionic radii of 35 ions have been calculated from published data of the average distances between the ions and the nearest water molecules, obtained by diffraction and computer simulation methods.     

二元混合离子液体的电导率与离子间的缔合作用

在293.15-323.15 K范围内, 测定了13种常见离子液体及其25组混合体系的电导率. 利用Vogel-Tammann-Fulcher (VTF)方程对电导率数据进行拟合, 并通过方程式中的拟合参数分析了离子液体混合后其阴阳离子间缔合作用的变化规律. 结果表明,在相同温度下, 离子液体的阳离子侧链越短,阴离子电荷越分散, 阴阳离子间的氢键作用力越弱,离子液体的电导率越大, 其中阴离子的影响比阳离子更明显.混合离子液体中离子间的缔合作用不仅与阴阳离子的种类有关,而且与混合物的组成有关.     

离子液体对木瓜蛋白酶催化特性的影响

研究了以1-丁基-3-甲基咪唑、四乙基铵及N-乙基吡啶为阳离子, 配以多种阴离子(H₂PO₄^-, ClO₄^-, HSO₄^-, CH₃COO^-, Cl^-, Br^-, NO₃^-, SCN^-, BF₄^-, PF₆^-)的离子液体对木瓜蛋白酶催化N-苯甲酰-L-精氨酸乙酯(BAEE)水解的活性及热稳定性的影响. 通过分析含离子液体体系中木瓜蛋白酶的水解活性和热力学失活参数, 发现该酶活性及稳定性与离子液体的Kosmotropicity性质无关. 因此, 离子的Hofmeister效应并不适合解释离子液体对木瓜蛋白酶催化特性的影响规律. 当以BF₄^-为阴离子, 改变阳离子结构时, 仅[BMIm][BF₄]可提高酶活性, 其它含官能团的咪唑类离子液体则降低酶活性, 但大部分离子液体明显提高木瓜蛋白酶的热稳定性. 在所研究的离子液体中, 基于PF₆^-或BF₄^-阴离子的离子液体可提高木瓜蛋白酶的活性及其热稳定性. 在含[BMIm][PF₆]介质中, 木瓜蛋白酶的水解活性最高; 在含[HOEtMIm][BF₄]介质中其热稳定性最好.