Photovoltaic Cells Involving the Nonconjugated Conductive Polymer Iodine-Doped Styrene-Butadiene-Rubber (SBR)

Novel photovoltaic cells involving a nonconjugated conductive polymer have been fabricated using titanium dioxide/doped styrene-butadiene-rubber/carbon on ITO coated PET substrates. Photocurrents and photo-voltages for different intensities of light (emission at 300–700 nm) have been measured. These cells have shown significantly higher photocurrents and photo-voltages compared to previous reports. A photocurrent density of about 0.25 mA/cm² and a photo-voltage of 0.74 V have been measured for a light intensity of ～4 mW/cm².     

染料敏化太阳能电池对电极La2Mo2O7复合MWCNTs非Pt催化剂的制备与性能

通过高温固相法对醋酸镧（C₆H₉O₆La·xH₂O）与高钼酸铵（（NH₄）₆Mo₇O₂₄·4H₂O）在一定条件下热解制备非Pt催化剂La₂Mo₂O₇（La₂O₃-2MoO₂）。进一步采用2种方法将La₂Mo₂O₇与多壁碳纳米管（MWCNTs）进行复合,一种是将La₂Mo₂O₇喷涂到MWCNTs表层之上得到La₂Mo₂O₇/MWCNTs,另一种是将两者均匀混合掺杂得到La₂Mo₂O₇@MWCNTs,再将上述2种复合材料应用于染料敏化太阳能电池对电极进行相应研究。通过扫描电子显微镜（SEM）表征了复合催化材料的微观形貌,X射线衍射（XRD）确定了微观结构。采用电流密度-光电压曲线、循环伏安,交流阻抗以及塔菲尔极化分析了材料的光电性能。实验结果表明在电解液I₃^-/I^-中,基于La₂Mo₂O₇/MWCNTs与La₂Mo₂O₇@MWCNTs的对电极,相同的条件下在光电池中获得的光电转换效率分别为6.09%和4.84%,明显高于MWCNTs的3.94%和La₂Mo₂O₇的0.87%。电极性能的提高可归因于La₂Mo₂O₇复合催化剂相对大的比表面积和高导电性。     

铕配合物共掺杂电致发光器件效率滚降的延缓

将Alq₃[tris(8-hydroxyquinoline)aluminium]和Eu(TTA)₃phen(TTA=thenoyltrifluoroacetone,phen=1,10-phenanthroline)共掺杂进入主体材料CBP(4,4’-N,N’-dicarbazole-biphenyl)中,我们制作并研究了一系列电致发光器件。经过优化Alq₃的掺杂浓度,在不改变色纯度的情况下,器件的效率滚降被大幅降低并获得了近乎加倍的最大亮度。发光层中的Alq₃分子不仅促进了电子的注入和传输,还延缓了空穴的传输。借助电致发光光谱,我们证实Alq₃分子作为阶梯加速空穴从CBP分子到Eu(TTA)₃phen分子的迁移,从而促进了电子和空穴在Eu(TTA)₃phen分子上的平衡。因此,我们认为器件的效率滚降受到抑制的原因有两点：一是复合区间的加宽,二是Eu(TTA)₃phen分子上空穴和电子的分布更加平衡。     

骨架结构多孔TiO2薄膜增强染料敏化太阳能电池性能

以空心球状TiO₂为基体、以片状TiO₂为骨架,采用刮刀法制备了染料敏化太阳能电池的多孔TiO₂光阳极薄膜。光电转化效率测试结果表明,当作为骨架支撑材料的片状TiO₂含量为20wt%时,光阳极薄膜组装成太阳能电池的光电转化效率达到最高值4.53%,比商业P25制备的无孔无骨架TiO₂薄膜电池(4.06%)及无骨架结构的多孔TiO₂薄膜电池(4.17%)的性能均有显著提高。当片状TiO₂的最佳含量为20wt%电池薄膜厚度为33 μm时,太阳能电池光电转化效率进一步提升为7.06%。光电性能增强的原因是骨架结构有利于快速传输电子并增大染料吸附量。本研究通过设计制备具有骨架结构的多孔TiO₂薄膜为提高染料敏化太阳能电池性能提供了新的思路。     

Comparison of sample preparation methods combined with gas chromatography with electron‐capture detection for the analysis of multipesticide residues in lotus seeds

Sample preparation is always the major bottleneck in analytical chemistry for the determination of pesticide residues. Different sample preparation methods have been proposed due to the wide variety of pesticides used and the inherent complexity of the matrices. In this study, different sample preparation methods including SPE, matrix solid‐phase dispersion, the quick, easy, cheap, efficient, rugged, and safe method, and a one‐step completion method were compared and evaluated for extracting pesticides from lotus seeds. Analysis was carried out using GC with electron‐capture detection. The results showed that good recoveries for tested pesticides were obtained by using Florisil in the four methods, and the extraction efficiency of the one‐step completion method was superior to the other three methods. The one‐step completion method was confirmed to have good linearity, reproducibility, stability, and recovery for the detection of 36 pesticides in lotus seed samples. The data collected from this study are expected to prove useful in regulating the concentration of the residues in lotus seeds, as well as in protecting human health from the hazards posed by these residues.     

SPE of 5‐lipoxygenase metabolites and the effect of head‐column field‐amplified sample stacking in MEKC

The SPE of leukotrienes and eicosatetraenoic acids using anion exchange materials was compared to the classical extraction with C₁₈ columns. A silica‐based strong anion exchanger, a polymer‐based weak anion exchanger, and a polymer‐based mixed‐mode strong anion exchanger were studied. All anion exchange materials displayed a higher recovery of the analytes with values between 70 and 90% when extracting standard solutions and analyzing by HPLC. The effect was less pronounced for the analysis of the compounds in incubations of polymorphonuclear leukocytes. Using MEKC with head‐column field‐amplified sample stacking for analyte quantification, much lower values of the peak areas were observed compared to the determination of the recovery of the analytes by HPLC. Using MEKC analysis, the highest values were found for the polymer‐based weak anion exchange material, while values below 10% were found for the polymer‐based mixed mode strong anion exchanger. This could be attributed to the presence of electrolytes in the eluates that compromised the stacking efficiency. The extent of residual electrolytes depended on the SPE protocol, resulting in large differences of the amount of analyte determined by MEKC when applying head‐column field‐amplified sample stacking for online analyte concentration.     

聚合物光伏材料与器件研究进展

高效率的聚合物太阳电池依赖于光吸收活性层材料对太阳光能量的充分利用．电极界面材料将光吸收活性层产生的空穴和电子分别快速高效地抽取到阳极和阴极,并通过进一步改进光伏器件的结构提升能量转换效率和稳定性．本课题组在光吸收活性层中新型聚合物给体材料、新型电极界面材料、利用水／醇性电极界面材料制作新型倒装器件结构的太阳电池方面取得重要进展,推动了太阳电池在能量转换效率和稳定性方面的突破．     

Automation of dimethylation after guanidination labeling chemistry and its compatibility with common buffers and surfactants for mass spectrometry-based shotgun quantitative proteome analysis

Isotope labeling liquid chromatography–mass spectrometry (LC–MS) is a major analytical platform for quantitative proteome analysis. Incorporation of isotopes used to distinguish samples plays a critical role in the success of this strategy. In this work, we optimized and automated a chemical derivatization protocol (dimethylation after guanidination, 2MEGA) to increase the labeling reproducibility and reduce human intervention. We also evaluated the reagent compatibility of this protocol to handle biological samples in different types of buffers and surfactants. A commercially available liquid handler was used for reagent dispensation to minimize analyst intervention and at least twenty protein digest samples could be prepared in a single run. Different front-end sample preparation methods for protein solubilization (SDS, urea, Rapigest™, and ProteaseMAX™) and two commercially available cell lysis buffers were evaluated for compatibility with the automated protocol. It was found that better than 94% desired labeling could be obtained in all conditions studied except urea, where the rate was reduced to about 92% due to carbamylation on the peptide amines. This work illustrates the automated 2MEGA labeling process can be used to handle a wide range of protein samples containing various reagents that are often encountered in protein sample preparation for quantitative proteome analysis.     

Temperature Effect on the Phase Behavior of the Systems Water/Sucrose Laurate/Ethoxylated‐mono‐di‐glyceride/Oil

The phase behavior of the systems water/sucrose laurate/ethoxylated mono‐di‐glyceride/oil was investigated as function of temperature and the weight ratio of EMDG in the mixed surfactants. The oils were R (+)‐limonene, isopropylmyristate, and caprylic‐capric triglyceride. This study demonstrates that the phase inversion temperature (PIT) decreases and the efficiency of the mixed surfactants (γ¯) increase as the weight ratio of the EMDG in the mixed surfactants increases. R (+)‐limonene gave lower phase inversion temperatures and higher efficiencies compared to isopropylmyristate, and caprylic‐capric triglyceride. The solubilization capacity of the system water/sucrose laurate/oil increased upon the addition of ethoxylated mono‐di‐ glyceride which stabilize the surfactant layer and increase the interfacial area.