聚乙烯醇缩丁醛准固态电解质薄膜的制备和性能表征

研究了聚乙烯醇缩丁醛准固态电解质薄膜的制备及相关性能.通过向聚乙烯醇缩丁醛中加入适量造孔剂和辅助剂制备电解质薄膜,研究了薄膜制备过程中的相关影响因素和不同孔隙率的电解质薄膜对电池光电转换效率的影响.实验表明,通过向0.200g聚乙烯醇缩丁醛中加入6.000g碳酸钙、0.310g氯化钙和0.150g葡萄糖所制备的电解质薄膜性能最优,用其制备的染料敏化太阳能电池光电转换效率η=4.720%(开路电压Voc=0.7194V,短路电流密度Jsc=10.014mA·cm-2,填充因子FF=0.6559),达到相同条件下液态电解质电池的88%以上.薄膜电解质制备简单,封装方便,所用原料无毒无害,具有一定的发展潜力.     

纳米氧化镍浓度对磁性准固态染料敏化太阳能电池的影响

以琼脂糖为聚合物基质,N-甲基-2-吡咯烷酮(NMP)为溶剂,磁性纳米氧化镍颗粒作为添加剂用于制备染料敏化太阳能电池(DSSC)的磁性聚合物电解质。通过SEM与离子电导率测试研究不同纳米氧化镍掺杂浓度对磁性聚合物电解质的影响,并对相应的染料敏化太阳能电池进行光电性能测试与电化学交流组抗谱(EIS)测试,结果表明:1.0wt%的纳米氧化镍掺杂浓度为最优掺杂浓度,在此浓度下聚合物电解质的表面形貌较为平整,同时电解质具备最高离子电导率(2.43×10-3S.cm-1);染料敏化太阳能电池的光电效率与电子寿命均随着纳米氧化镍掺杂浓度的增加而先增加后降低,并都在纳米氧化镍掺杂浓度为1.0wt%达到最大,此时电池的光电效率为1.63%、开路电压为0.57 V、短路电流密度为5.8 mA.cm-2、填充因子为0.53。     

染料敏化太阳能电池用琼脂糖基磁性聚合物电解质的电化学性能

以琼脂糖为聚合物基质,N-甲基吡咯烷酮为溶剂,磁性纳米粒子四氧化三铁为无机纳米颗粒添加剂制备了用于染料敏化太阳能电池(DSSC)的磁性聚合物电解质.通过研究不同小分子表面活性剂,聚乙二醇(PEG200)、曲拉通(TritonX-100)、乙酰丙酮和三者混合的表面活性剂对掺杂有1%(w)Fe3O4的磁性聚合物电解质离子电导率的影响,发现PEG200的加入可有效提高琼脂糖基磁性聚合物电解质的离子电导率.同时,对不同PEG200浓度添加下的电解质进行离子电导率测试研究发现:当PEG200加入量为61.8%(w)时,电解质具有最佳的离子电导率(2.88×10-3S·cm-1);对染料敏化太阳能电池进行电化学交流阻抗谱(EIS)测试的结果表明:染料敏化太阳能电池的电子寿命和复合电阻随着PEG200浓度的增加是先增大后减小,最大的电子寿命和复合电阻出现在PEG200浓度为68.3%(w)处.     

新型梳状共聚物在准固态染料敏化太阳能电池中的应用及其对电子复合的影响

合成了乙烯基咪唑碘盐(VImI)和聚乙二醇单甲醚甲基丙烯酸酯(PEGMA)的梳状共聚物.利用VImI/PEGMA共聚物制备了准固态聚合物电解质.通过光电流密度-电压(J-V)曲线和电导率测定以及电化学阻抗分析,探讨了基于此电解质的染料敏化太阳能电池的电荷传输与界面电子转移机制.结果表明,VImI/PEGMA共聚物可以有效抑制TiO2/电解质界面电子复合并提高TiO2导带能级,敏化电池的光伏性能并不完全取决于电解质的电导率.通过考察共聚物中VImI与PEGMA单元的摩尔比与开路电压的关系,发现共聚物对电子复合的抑制作用主要源于VImI链段.此外,开路电压衰减(OCVD)和瞬态光电流测试结果说明,共聚物能够提高TiO2薄膜的电子寿命,而且对陷阱电子能级的分布具有调节作用.当共聚物在电解质中的质量分数为50%,VImI与PEGMA的摩尔比为5.0时,准固态染料敏化太阳能电池于100mW·cm-2光强下获得了4.10%的光电转换效率.     

聚合物电解质在染料敏化太阳能电池中的应用进展

染料敏化太阳能电池(DSSC)由于成本低、污染小、制备工艺简单而受到广泛关注。电解质在其中起到桥梁的作用,能促使染料再生、输运空穴,从而完成整个光电循环过程,是DSSC重要的组成部分。本文简要介绍了DSSC的基本结构和工作原理,指出了传统液态电解质存在的问题,综述了近年来以聚合物为基体制备的新型固态聚合物电解质、凝胶聚合物电解质以及多孔聚合物电解质在DSSC中的应用,最后对聚合物电解质在染料敏化太阳能电池中的发展做出了展望。     

准固态聚合物电解质在染料敏化太阳能电池中的应用

将固态或准固态聚合物电解质应用到染料敏化太阳能电池(DSSC)中可以有效解决应用液态电解质遇到的封装难、稳定性差等问题,因而近年来,对固态和准固态电解质的研究引起了广泛关注.本文就准固态聚合物电解质在DSSC中应用的研究进展及存在的问题进行了综述.同时,介绍了DSSC的结构及工作原理.根据目前DSSC准固态聚合物电解质...     

PEDOT的电化学合成及其在固态染料敏化太阳能电池中的应用研究

本工作主要围绕PEDOT的合成及其在固态染料敏化太阳能电池对电极中的应用开展研究,重点研究了循环伏安法电化学沉积过程中循环次数(10～50次)对PEDOT薄膜的形貌、厚度及光学性质的影响.通过红外光谱、SEM、紫外-可见吸收光谱表征了PEDOT的结构、形貌及光性质;通过J-V、动态调制光电流谱(IMPS)/光电压谱(IMVS)以及Tafel测试表征了基于PEDOT透明对电极染料敏化太阳能电池的光电化学性能.结果表明:采用循环伏安法电沉积合成PEDOT制备固态染料敏化太阳能电池对电极时,CV循环30～40次之间时可以获得最佳的光电性能,固态器件的光电转换效率为5.34%,这是因为在该条件下所制备的PEDOT具有均匀致密的表面、较好的光学性质以及较高的光电催化性能(J₀=2.51×10^-3A·cm^-2),使得器件可以获得较大的扩散系数(D_n=28.80μm²·ms^-1)和载流子扩散长度(L=21.41μm),有利于电荷的传输.当CV循环次数大于40次时,PED...     

染料敏化太阳电池用电解质的研究进展

染料敏化太阳能电池(DSCs)由于其清洁廉价的优点而受到广泛关注。经过多年的研究,目前电池的转换效率已十分可观。电解质在染料敏化太阳能电池中起到桥梁作用,担负着还原染料、输运载流子完成电池内部循环的作用。电解质根据物理状态不同将其分为液态电解质、准固态电解质和固态电解质。介绍了这三种不同电解质的性能、各自的优点及存在问题,并对染料敏化太阳能电池中电解质在国内外研究发展现状进行了综述。     

准固态染料敏化太阳能电池中电解质体系的研究进展

染料敏化太阳能电池(Dye Sensitized Solar Cells)是新一代将光能转化为电能的重要能源转换装置。它具有低廉的材料和器件制作成本、较高的光电转换效率以及电池制作过程简单等诸多优点,拥有广阔的应用空间和巨大的潜在商业价值,因而吸引了广泛的研究关注。染料敏化太阳能电池主要由染料敏化的光阳极、电解质和对电极三个部分组成。其中,电解质作为染料敏化太阳能电池的重要组成部分,其对离子的传导和扩散,以及促进染料再生的能力极大地影响着染料敏化太阳能电池的电荷传输和光电性能。本文聚焦于染料敏化太阳能电池准固态电解质体系,主要从聚合物凝胶电解质、有机小分子凝胶电解质和无机纳米粒子凝胶电解质三大方面综述讨论了该研究领域当前最新研究进展,并对其未来研究趋势进行了展望。     

用于聚合物镍氢电池的新型PVA/SiO2碱性微孔聚合物电解质

采用溶胶凝胶法,结合相转移法和碱液活化法制备了PVA/SiO2碱性微孔聚合物电解质,通过SEM、XRD、交流阻抗法和循环伏安法表征了电解质的结构与电化学性能.研究表明,PVA/5ωSiO2(ω为质量分数)共混膜上的微孔大小合适,聚合物电解质的离子电导率最大可达1.62×10-2 S·cm-1,电化学稳定窗口2V以上;将PVA/SiO2碱性微孔电解质组装成聚合物镁基镍氢电池,与传统镍氢电池相比,循环稳定性大大增加.     

Comparison of the preparation of PLGA–BSA nano- and microparticles by PVA, poloxamer and PVP

The objective of our study was to prepare nano- and microparticles economically considering some practical parameters such as size and encapsulation efficiency as well as ability of particle recovery. Bovine serum albumin (BSA) model protein was encapsulated by poly(d,l-lactide-co-glycolide) (PLGA) using a multiple water-in-oil-in-water emulsion-solvent evaporation technique. The effect of three surfactants: polyvinyl alcohol, poloxamer, and polyvinyl pyrrolidone, used in the outer water phase, on the properties of particles was investigated. The emulsifier/PLGA mass ratio played an important role in the preparation procedure of the particles. This ratio was found to be approximately 1 for polyvinyl alcohol (PVA) if the aim was to formulate nanoparticles with narrow size distribution (<220 nm), high yield and good encapsulation efficiency (>90%). Although, a ratio of 2:1 was sufficient to produce submicron particles by poloxamer with high yield, more than 70% and 90% encapsulation efficiency required minimum 4 and 10 emulsifier/PLGA mass ratio, respectively. Five times more PVA and 10 times more poloxamer than the PLGA mass were necessary to obtain nanoparticles which were easy to redisperse after centrifugation. Microparticles released more BSA than nanoparticles prepared by PVA, however, the situation was reverse with poloxamer. Microparticles formulated by polyvinyl pyrrolidone (PVP) showed the fastest in vitro release.     

采用新型引发剂乳液聚合法合成高相对分子质量聚乙烯醇

采用新型引发剂偶氮二异(N-胺乙基)丁脒(ABEA)对醋酸乙烯酯的低温乳液聚合进行了研究。通过正交试验得出了高相对分子质量聚醋酸乙烯酯的最佳工艺配方。讨论了引发剂浓度、反应温度和乳化剂浓度对聚合物相对分子质量和转化率的影响。对高相对分子质量聚醋酸乙烯酯醇解工艺进行了探讨,并获得了聚合度为3500~4000的聚乙烯醇。     

Facilitated transport of CO2 in novel PVAm/PVA blend membrane

A defect-free ultra thin PVAm/PVA blend facilitated transport membrane cast on a porous polysulfone (PSf) support was developed and evaluated in this study. The target membrane was prepared from commercial polyvinyl amine (PVAm) and polyvinyl alcohol (PVA). Effects of experimental conditions were investigated for a CO₂–N₂ mixed gas. A CO₂/N₂ separation factor of up to 174 and a CO₂ permeance up to 0.58 m³(STP)/(m² h bar) were documented. Experimental results suggest that CO₂ is being transported according to the facilitated transport mechanism through this membrane. The fixed amino groups in the PVAm matrix function as CO₂ carriers to facilitate the transport whereas the PVA adds mechanical strength to the blend by entanglement of the polymeric chains hence creating a supporting network. The good mechanical properties obtained from the blend of PVA with PVAm, enabled an ultra thin selective layer (down to 0.3 μm) to be formed on PSf support (with MWCO of 50,000), resulted in both high selectivity and permeance. The PVAm/PVA blend membrane also exhibited a good stability during a 400 h test.     

层状水凝胶仿生软骨的制备与性能

采用超声分散、高压加热共融、冷冻-熔融和γ射线辐照交联成型工艺制备层状水凝胶仿生软骨材料, 系统讨论了PVP添加量和辐照剂量对材料的凝胶含量、晶态结构及抗压缩弹性模量的影响, 观察和研究了层状水凝胶的微观结构. 研究结果表明, 随着PVP的质量分数(0-40%)和辐照剂量(0-60 kGy)的增加, 层状水凝胶的凝胶含量呈上升趋势; 其晶态结构在质量分数为20%的PVP和10 kGy辐照剂量下最完善; 其力学性能在质量分数为20%的PVP和20 kGy辐照剂量下最佳; PVP的加入改善了水凝胶的微观形貌, 有利于材料表面润滑性能的提高; 层状水凝胶层间渗透结合, 自然过渡, 形成结构良好的仿生软骨材料.     

α-Co(OH)_2的制备及其超级电容特性

以氯化钴为原料,聚乙烯吡咯烷酮(PVP)为分散剂,采用化学沉淀的方法制备出由纳米粒子组成的片状α-Co(OH)2.用红外光谱对所制样品的组分进行分析,用X射线衍射和场发射扫描电子显微镜表征产物的结构和形貌,用循环伏安和恒电流充放电等测试方法对其电化学性能进行研究.研究结果表明,由纳米粒子组成的片状α-Co(OH)2表现出优良的电化学性能,单电极比电容高达1220 F/g.     

PREPARATION AND THE CULTURE OF LO2 CELLS ON PVA—BASED MICROCARRIERS

Using polyvinyl alcohol(PVA) as raw material and vacuum pump oil as oil phase medium,PVA-based microcarriers were prepared by suspension method,The diameters of the beads were 100-180um,LO2 cells were cultured on PVA-based microcarriers and cytodexⅢ microcarriers.Morphology,attachment and growth rate of LO2 cells were studied.     

THE EFEFCT OF MAGNETIC FIELD ON POLYMERIZATION OF STYRENE IN THE PRESENCE OF POLYVINYL NAPHTHALENE AND POLYVINYL BENZOPHENONE

In the process of bulk photopolymerization of styrene initiated by AIBN decomposition polyvinyl benzophenone (PVB) can supply an effective cage for triplet-triplet energy transfer between PVB macromolecules and small molecules of AIBN to influence the molecular weight of polystyrene in weak magnetic field (less than 0.035T), that was different from the case of polyvinyl naphthalene (PVN) which supplied cages for this system only in the stronger magnetic field (more than 0.2 T) studies. It was found that in the same conditions, PVN could exert more tremendous influences on the bulk photopolymerizatiou system of styrene than PVB because in the stronger magnetic field the triplet PVN had much longer life time than PVB.     

PREPARATION AND THE CULTURE OF LO2 CELLS ON PVA-BASED MICROCARRIERS

1. INTRODUCTION Biological artificial liver support systems have been extensively studied in treatment of hepatic failure [1]. In the device, cells included primary hepatocytes [2] and liver cell lines (i.e. C3A, HepG2 [3]) with relatively high differentiations, which are all attachment dependent cells; the cell density is crucially important for its efficiency in clinical application. Microcarrier -attached hepatocytes have been applied in the device in an attempt to raise the cell dens…     

Single-Phase Polymer Alloys of Polyvinyl Chloride and New Polymers

Polymer alloying is acquiring ever increasing significance for the modification of polymeric materials. Polymer alloys are defined by their phase character, which in turn is determined by the mutual compatibility or incompatibility of the components. Suitable techniques for the analysis of the phase character include, inter alia, dynamic-mechanical methods, according to which a polymer alloy may be considered in a simplified manner as single-phase when only one glass transition is observed, even if it extends over a broader temperature range than in the case of the pure components. Aliphatic (polyester)-polycarbonates and tetramethylbisphenol-A polycarbonate are new, PVC-compatible, polymer modifiers. The (polyester)-polycarbonates (from adipic acid, hexane-1,6-diol, neopentanediol, and diphenyl carbonate) yield with PVC single-phase alloys that at temperatures above the glass transitions of the mixture display the characteristics of soft PVC and that are tough far below this temperature. The special high-temperature properties of the resin-like tetramethylbisphenol-A polycarbonate permits the preparation of alloys with increased dimensional stability under heat (higher deflection temperatures under load).     

左氧氟沙星选择性电极的制备及其性能研究

以左氧氟沙星与四苯硼酸根形成的缔合物为电活性物质,研制了一种左氧氟沙星PVC膜涂层玻璃电极,并对其响应性能进行了系统研究.实验表明,该电极的Nernst响应范围为5.0×10-3～2.0×10-5 moL/L,斜率为51.7 mV/pC,适用pH范围为3.0～4.5.该电极制作方法简单,响应迅速,重现性好,用于左氧氟沙星注射液和片剂的测定.