塑晶基离子液体合成及其电化学性能

通过简单、易于工业化的重结晶方法制备了高纯1-甲基-1-乙基吡咯烷鎓双(三氟甲基磺酰)亚胺盐(P₁₂TFSI)塑晶化合物. 在此化合物中加入30% (摩尔分数, x)双(氟磺酰)亚胺锂(LiFSI)后, 得到P₁₂TFSI/LiFSI 塑晶基离子液体. 采用循环伏安法、恒电压极化法及恒电流充放电法等电化学方法考察了该离子液体的电化学窗口、铝箔集流体的腐蚀性及电池性能. 结果表明, 该离子液体电解质具有5.00 V的电化学窗口, 室温离子电导率达到0.92 mS·cm^-1, 且不腐蚀Al 集流体. 以该塑晶离子液体作为电解液组装的实验电池LiCoO₂/Li 表现出良好的充放电特性及循环性能, 在较低倍率下能够和使用碳酸酯类电解液组装的实验电池的性能相媲美. 在4.50 V高电压下, 循环20周后, 容量仍能保持在175 mAh·g^-1, 容量保持率为95.1%. 这些结果说明该离子液体在高性能锂二次电池中具有良好的应用前景.     

Molecular fragmentations : Part XIII. The structures and energies of mass spectral fragments derived from phosphine-3, diphosphine-4, diphosphine-2 and triphosphine-5

Structures and energies have been calculated, in the MNDO approximation, for PH₃, P₂H₄, P₂H₂, and P₃H₅, for their molecular cations, for all the ions in their mass spectra, and for the corresponding neutral mass spectral fragments. With the exception of the conformation of P₂H₄, which is calculated to be anti rather than gauche, the calculated structures and energies are in good agreement with those found experimentally, where these are known. Appearance potentials have been calculated, and allow deductions to be made concerning fragmentation pathways.     

Fabrication of solid thin film electrolyte and LiCoO2 by aerosol flame pyrolysis deposition

Aerosol flame pyrolysis deposition method was applied to deposit the oxide glass electrolyte film and LiCoO₂ cathode for thin film type Li-ion secondary battery. The thicknesses of as-deposited porous LiCoO₂ and Li₂O–B₂O₃–P₂O₅ electrolyte film were about 6 μm and 15 μm, respectively. The deposited LiCoO₂ was sintered for 2 min at 700 °C to make partially densified cathode layer, and the deposited Li₂O–P₂O₅–B₂O₃ glass film completely densified by the sintering at 700 °C for 1 h. After solid state sintering process the thicknesses were reduced to approximately 4 μm and 6 μm, respectively. The cathode and electrolyte layers were deposited by continuous deposition process and integrated into a layer by co-sintering. It was demonstrated that Aerosol flame deposition is one of the good candidates for the fabrication of thin film battery.     

具有Dawson结构的钼钒磷杂多酸氧化还原性质的研究

通过SnCl₂电位滴定、极谱和循环伏安方法,详细研究了2:18系列钼钒磷杂多酸H_(6+n)[P₂Mo^13-nV_nO₆₂]·xH₂O(n=1～3)和H^_4+n[P₂Mo_18-nV_nO₆₂H₂]·xH₂O(n=4,5)在溶液中的氧化还原性质,证实它们的还原为三步分别加合n,2,2个电子,同时加合n,2,2个质子的过程,总结了循环伏安峰电位与pH的关系,提出了还原机理。     

Mesomorphic properties of liquid crystalline polysiloxanes and elastomers based on a tri-vinyl crosslinker

A series of crosslinked liquid crystalline polymers and the corresponding uncrosslinked liquid crystalline polymers were prepared by graft copolymerization; their liquid crystalline properties were characterized by DSC, POM and X-ray measurements. The results show that the crosslinking obtained in the isotropic state leads to a reduction of the clearing point (T_c) of the crosslinked polymers, as compared with the corresponding uncrosslinked polymers. The crosslinked polymers with low crosslinking density (P₁-P₇) exhibit nematic mesogenic phases, as do the uncrosslinked polymers. In contrast, a high crosslinking density leads to the crosslinked polymers P₈ and P₉ losing their thermotropic liquid crystalline phases; they instead exhibit stress-induced orientation.     

钒取代的Dawson型磷钼酸对酪氨酸酶的抑制作用

采用酶动力学方法研究了5种钒取代的Dawson型磷钼酸H₇[P₂Mo₁₇VO₆₂]、H₈[P₂Mo₁₆V₂O₆₂]、H₉[P₂Mo₁₅V₃O₆₂]、H₈[P₂Mo₁₄V₄O₆₂H₂]和H₉[P₂Mo₁₃V₅O₆₂H₂](分别简写为P₂Mo₁₇V、P₂Mo₁₆V₂、P₂Mo₁₅V₃、P₂Mo₁₄V₄和P₂Mo₁₃V₅)对蘑菇酪氨酸酶二酚酶的抑制作用,结果表明,效应物P₂Mo₁₇V、P₂Mo₁₆V₂和P₂Mo₁₅V₃能够明显地抑制酪氨酸酶的活性,其半抑制浓度(IC₅₀)值分别为0.409、0.386和0.386 mmol/L,且均表现为可逆的竞争型抑制,效应物P₂Mo₁₇V、P₂Mo₁₆V₂和P₂Mo₁₅V₃对游离酶的抑制常数K_I分别为0.234、0.391和0.249 mmol/L。 而效应物P₂Mo₁₄V₄在0~1.0 mmol/L浓度范围内,对酪氨酸酶二酚酶无明显抑制作用,效应物P₂Mo₁₃V₅对酪氨酸酶二酚酶表现为激活作用。     

Organic ionic plastic crystal as electrolyte for lithium-oxygen batteries

Organic ionic plastic crystal composed of 1-ethyl-1-methyl pyrrolidinium bis(fluorosulfonyl)imide (P₁₂FSI) and lithium bis(fluorosulfonyl)imide (LiFSI) was used as electrolyte for lithium-oxygen battery. The battery at room temperature delivered a superior long life (320 cycles) and good rate capability since the electrolyte had good chemical and electrochemical stability, and high ionic conductivity.     

铜配合物修饰的Dawson型钨磷酸盐的合成、晶体结构和催化性能

在水热条件下,Cu(Ⅱ)-H₂biim配合物与Dawson型钨磷酸盐构筑了1个无机-有机杂化化合物[Cu(H₂biim)₂(H₂O)][{Cu(H₂biim)₂}₂(P₂W₁₈O₆₂)]·11H₂O(1)(H₂biim=2,2'-联咪唑)。 通过单晶X射线衍射、红外光谱(IR)、X射线粉末衍射(XRD)、元素分析、电化学分析等技术手段对其进行了表征。 结构分析表明,在化合物1分子中,[P₂W₁₈O₆₂]^6-单元作为双齿配体与2个Cu²⁺离子配位形成双支撑的杂多阴离子[{Cu(H₂biim)₂}₂(P₂W₁₈O₆₂)]^2-,在其外部有1个游离的[Cu(H₂biim)₂(H₂O)]²⁺ 和11个H₂O分子。 H₂biim分子与杂多阴离子/H₂O分子间存在氢键,通过氢键、静电和π-π堆积作用,进一步构成具有3D结构的晶体材料。 该晶体化合物对H₂O₂和NaNO₂的还原具有良好的电催化作用;同时,作为酸催化剂用于合成环己酮乙二醇缩酮反应,催化活性高,可重复使用。     

盘状多酸P_5W_(30)/阳离子聚电解质/氧化石墨烯杂化多层膜的电致变色性能

为了提高薄膜[PEI/P_5W_(30)]_(30)的电致变色性能,将具有大的二维尺寸和良好导电性的氧化石墨烯引入该薄膜中。通过层层自组装(LBL)技术构筑了基于盘状多酸K12.5Nal.5[Na P_5W_(30)O_(110)]·15H_2O(P_5W_(30))、氧化石墨烯(GO)的复合薄膜[PEI/P_5W_(30)/PEI/GO]_(30)(PEI:聚乙烯亚胺),并利用UV-Vis光谱对薄膜的组成及增长进行监测;通过原子力显微镜对薄膜的表面形貌进行考察,利用循环伏安法对薄膜电化学氧化还原性质进行研究;薄膜在外加氧化还原电位下呈现出无色/蓝色的可逆变化,电致变色响应时间在10 s以内;此外,薄膜在阶跃电位0.75 V/-0.75 V下循环150次,电致变色性能没有明显减弱,体现了薄膜良好的电致变色可逆性。氧化石墨烯的引入使薄膜[PEI/P_5W_(30)/PEI/GO]_(30)呈现出响应速度快、抗电疲劳强的电致变色性能,将在电致变色器件领域有广阔的应用前景。     

Hydrothermal Synthesis,Structure and Properties of a New Phosphomolybdate Based on Novel [Co(H2O)4(HP2Mo5O23)]8- Anions and [H8(H2O)16]8+ Water Cluster Cations

A pure inorganic [P₂Mo₅O₂₃]^6- based cobalt complex [H₈(H₂O)₁₆][Co(H₂O)₄(HP₂Mo₅O₂₃)₂] with a sandglass-like shape was synthesized and characterized by means of single-crystal X-ray diffraction, powder X-ray diffraction(PXRD), infrared spectroscopy(IR), thermogravimetry/differential scanning calorimetry(TG/DSC), ultraviolet-visible spectroscopy(UV-Vis) and cyclic voltammogram(CV). Single-crystal X-ray diffraction analysis reveals that the asymmetric unit of compound 1 consists of a half cobalt ion, one [P₂Mo₅O₂₃]^6- anion, two coordinated water molecules and eight lattice water molecules. It is especially intriguing to note that two [P₂Mo₅O₂₃]^6- clusters are symmetrical about the Co ion, like a sandglass. And a chair-like water cluster with an unprecedented centrosymmetric [H₈(H₂O)₁₆]⁸⁺ can be observed in compound 1. Additionally, the electrochemical and catalytic properties of compound 1 were also investigated.     

Small angle X-ray scattering study of chiral side chain liquid crystalline polymers in 5CB and 8CB solvents

Small angle X-ray scattering was used to examine the new chiral side chain liquid crystalline polyacrylates (P_4M and P_11M) and their mixtures (2 wt %) in the low molar mass nematogenics 4'-n-pentyl-4-cyanobiphenyl (5CB) and 4'-octyl-4-cyanobiphenyl (8CB). Complementary data were obtained by polarizing optical microscopy. In agreement with previous studies, the mesophases of the bulk polymers show a dependence on the aliphatic spacers linking the mesogenic units to the polymer backbone. Chiral nematic and smectic A₁ phases were observed for the polyacrylates with four (P_4M) and eleven (P_11M) methylene units as spacers, respectively. In solution with 5CB and 8CB, P_4M exhibits an injected smectic phase, whereas P_11M maintains the smectic arrangement already observed in the bulk, with swollen smectic layers. In all the mixtures, layer stability was found to depend on the liquid crystal used as solvent, as well as on the temperature. At temperatures corresponding to the nematic 5CB and 8CB, the coexistence of two mesophases was observed in the mixtures. Moreover, with the liquid crystal solvents in the isotropic phase, microstructures suspended in the solvent matrix containing the liquid crystalline polymer in the smectic arrangement were detected.     

固态锂电池中正极/电解质界面的密度泛函计算研究

锂离子电池的广泛应用对储能器件的能量密度、安全性和充放电速度提出了新的要求. 全固态锂电池与传统锂离子电池相比具有更少的副反应和更高的安全性,已成为下一代储能器件的首选. 构建匹配的电极/电解质界面是在全固态锂电池中获得优异综合性能的关键. 本文采用第一性原理计算研究了固态电池中电解质表面及正极/电解质界面的局域结构和锂离子输运性质. 选取β-Li₃PS₄ (010)/LiCoO₂ (104)和 Li₄GeS₄ (010)/LiCoO₂ (104)体系计算了界面处的成键情况及锂离子的迁移势垒. 部分脱锂态的正极/电解质界面上由于Co-S成键的加强削弱了P/Ge-S键的强度,降低了对Li⁺的束缚,从而导致了更低的锂离子迁移势垒. 理解界面局域结构及其对Li+输运性质的影响将有助于我们在固态电池中构建性能优异的电极/电解质界面.     

铈(Ⅳ)与焦磷酸盐的配位作用

考察了在焦磷酸盐水溶液中用O₃氧化Ce(Ⅲ),生成的Ce(Ⅳ)与P₂O₇^4-的作用情况,并对不同条件下所得的固体进行了研究。     

磷对泥/煤混燃灰熔融特性的影响及矿物相演变规律

采用灰熔点仪、X射线荧光仪(XRF)研究了无机非金属P2O5对城市污水污泥与烟煤的混烧灰熔融特性的影响,利用X射线衍射仪(XRD)、X射线光电子能谱仪(XPS)研究在各混烧温度下灰中含磷矿物在晶体和非晶体间的演变。结果表明,对于Al_2O_3含量较多且熔点较高的灰样,磷含量的增加可显著降低其灰熔点,P2O5含量在0-4%时影响最大,使其灰熔点降低126℃;但对碱性含量高的灰样的影响较小。低温灰中主要以磷酸铝(AlPO_4)晶体为主,温度升高后,与硬石膏(CaSO_4)等含钙矿物和赤铁矿(Fe_2O_3)反应生成晶体Ca_3(PO_4)_2和玻璃相(Fe_2O_3)_(0.252)(P_2O_5)_(0.748),磷含量增加可使灰中玻璃相(Fe_2O_3)_(0.252)(P_2O_5)_(0.748)增加,是磷降低灰熔点的主要原因。     

钙钛矿CH3NH3PbI3晶体的电化学

电化学方波伏安及循环伏安测量表明,钙钛矿CH₃NH₃PbI₃晶体在有机电解质中的氧化还原过程伴随着化学降解。该化学降解源于CH₃NH₃PbI₃晶体中铅离子的还原以及碘离子的氧化。通过电化学伏安法可以测定晶体的能带。     

含磷活性炭作为双电层电容器电极材料的电化学性能

采用磷酸活化和磷酸改性制备了不同种类的含磷活性炭,采用元素分析、X射线光电子能谱(XPS)和氮气吸附等手段分析了活性炭的元素含量、表面化学性质和孔隙结构,采用恒电流充放电、循环伏安和交流阻抗分别考察了活性炭在KOH和H₂SO₄电解质溶液中作为超级电容器电极材料的电化学性能,采用自由截距多元线性回归拟合统计分析研究了活性炭电极比电容量的影响因素,应用三电极体系分析了磷元素对活性炭电化学性能的影响机理。研究结果表明,活性炭掺杂的磷引入了赝电容,提高了活性炭电极的比电容量,磷元素含量为5.88%(w)的活性炭的比电容量在0.1 A·g^-1下达到185 F·g^-1。统计分析结果显示,活性炭的中孔有利于电解质离子向微孔内的扩散。在6 mol·L^-1 KOH电解质溶液中,孔径在1.10-1.61 nm、2.12-2.43nm及3.94-4.37 nm范围内是电解质离子在活性炭孔隙内部形成双电层的主要场所;在1 mol·L^-1 H₂SO₄电解质溶液中,孔径在0.67-0.72 nm范围内有利于双电层电容的形成。     

HBF4溶液中全铅液流电池

报道了一种HBF₄水溶液中的全铅液流电池,正、负电极电解液均采用Pb（BF₄）₂的HBF₄水溶液.在酸性的四氟硼酸铅电解液中考察了石墨电极和玻碳电极作为工作电极的循环伏安性能,石墨电极较适于用作全铅液流电池的正、负电极.采用石墨电极作为电池的正、负电极并在四氟硼酸铅酸性电解液中进行充放电实验,其中Pb（BF₄）₂浓度分别为0.5、1.0和1.5 mol·L^-1,且保持游离的HBF₄浓度为1.0 mol·L^-1.该电池为单液流电池,不需要隔膜分隔正、负极的电解液,电流密度为10、20和40 mA.cm^-2,当限定充电容量为7.0 mAh.cm^-2,放电电压截止到1.0 V时,平均库仑效率大于87%,平均能量效率大于68%;当电解液采用1.0或1.5 mol·L^-1 Pb（BF₄）₂+1.0 mol·L^-1HBF₄水溶液时,在10及20 mA.cm^-2电流下的能量效率最高可超过74%.     

纤维素凝胶电解质及其在超级电容器中的应用

以纸浆为原料制备得到一种粘胶液,经静置水化交联,得到一种纤维素凝胶电解质(XWD-NaOH);添加亚铁氰化钾,使获得的新型纤维素凝胶电解质(XWD-NaOH-K 4[Fe(CN)6])呈现良好的氧化还原活性,电导率达15.3 mS/cm;与XWD-NaOH相比,XWD-NaOH-K 4[Fe(CN)6]电解质超级电容器,在0.5 A/g电流密度下,比电容、功率密度和能量密度分别提高了57%、111%和214%,并且体系具有更低的内阻、电荷转移电阻及高的循环稳定性。     

Relative stabilities of the asymmetric OPOP, symmetric OPPO and cyclic conformations of P2O2

Various P₂O₂ planar isomers are investigated by molecular orbital calculations. Cyclic (¹A_g) is predicted to be more stable than OPOP (³A″-cis) and OPPO (¹A_g-trans) by 5.6 and 23.1 kcal/mol, respectively. The dimerization energy of 2PO→cyclic OPOP lies around 55 kcal/mol; the asymmetrical conformations OPOP and symmetrical OPPO are also bound. The computed vibrational frequencies and corresponding absorption intensities (derived at the SCF level) should help future experimental characterizations of these P₂O₂ isomers.     

钒钨酸盐/刚果红电致变色复合膜及器件研究

应用Layer-by-Layer自组装技术, 采用聚乙烯亚胺(PEI)阳离子将无机电致变色材料[P₂W₁₅V₃O₆₂]^8?(P₂W₁₅V₃)阴离子与刚果红(CR)阴离子通过静电引力复合, 构筑了复合膜[PEI/P₂W₁₅V₃/PEI/CR]₂₀及对比膜 [PEI/P₂W₁₅V₃]₂₀. 利用扫描电子显微镜、 紫外-可见吸收光谱和电化学工作站研究了复合膜的形貌与电致变色性能. 对比研究表明, 复合膜可实现浅红色-蓝紫色-浅红色的可逆颜色调变, 且保持了[P₂W₁₅V₃O₆₂]^8?阴离子的电致变色性能, 光反差22.55%, 着色效率122.67 cm²/C.复合膜循环测试400圈后透过率(500 nm)处损耗仅为6.94%, 稳定性良好; 由复合膜组装的电致变色器件也实现了由浅红色到蓝紫色的颜色变化. 本研究可为解决多酸电致变色材料颜色变化单一的问题提供参考.