小分子给体/高分子受体型有机太阳能电池研究进展

有机太阳能电池具有低成本、柔性和质量轻等优势, 是一种有应用前景的光伏技术, 受到人们的广泛关注. 有机太阳能电池的光敏活性层通常由p-型有机半导体(包括小分子和高分子)与n-型有机半导体(包括小分子和高分子)共混而成. 小分子给体/高分子受体型有机太阳能电池具有形貌热稳定性优异的特点, 值得深入研究. 本综述旨在总结小分子给体/高分子受体型有机太阳能电池的研究进展, 分别介绍了基于酰亚胺基、氰基和含硼氮配位键(B←N)的高分子受体的活性层材料体系的发展状况. 在器件性能方面, 通过分子设计、相分离形貌调控, 改善了小分子给体/高分子受体的匹配性, 将该类电池的能量转换效率从最初的0.29%提升至目前的9.51%, 为性能的进一步提升总结了经验; 在稳定性方面, 基于该体系形貌热稳定性优异的特点, 开发出高温耐受型有机太阳能电池器件. 最后, 展望了小分子给体/高分子受体型有机太阳能电池的未来发展方向和前景.     

Reaction Behaviors of S-, O-, and N-containing Aliphatic Molecules with a Propyl Moiety on Ge(100) Surface

The reaction pathways of 1-propanethiol, 1-propanol, and propylamine molecules, containing a propyl moiety, on a Ge(100) surface were investigated using high-resolution photoemission spectroscopy (HRPES) experiments and density functional theory (DFT) calculations. Upon analysis of the HRPES data, the adsorption of 1-propanethiol and 1-propanol was found to occur through a dissociation reaction, whereas that of propylamine took place via N dative bonding at room temperature. On the basis of our DFT results, adsorption geometries and transition states for each of these molecules on the Ge(100) surface were confirmed. Systematic studies of S-, O-, and N-containing molecules, composed of an identical propyl moiety, on the Ge(100) surface provide insight into the adsorption mechanism of aliphatic molecules containing alkyl chains on the Ge(100) surface.     

Magnetic Modulation in Heteroallene and Heterocumulene Based tert-butyl Nitroxide Diradicals: Spin Delocalization and Conformation Play Crucial Roles

We have theoretically investigated the magnetic properties of heteroallene (>C=C=X−) and heterocumulene (>C=C=C=X−) based tert-butyl nitroxide diradicals (X is P/As). Calculation of magnetic exchange coupling constant (J) shows ferromagnetic interaction in heteroallene based diradicals. Whereas, in heterocumulene based diradicals, tuning of J value from antiferro- to ferro-magnetic state is observed from Z- to E- isomer. Delocalization of spin density from radical site to the coupler (in planar arrangement) is observed in spin distribution analysis which is also advocated by molecular orbital analysis. The typical feature of tert-butyl nitroxide radical creates spin delocalization along with spin polarization within the coupler. The J values of all the diradicals strongly depend on the dihedral angle between radical center and coupler. Magneto-structural correlation shows that the change in dihedral angle tunes the magnetic property for both the Z- and E- isomers of heterocumulenes depending on the spin accumulation on two nearby magnetic centers. The extent of spin delocalization and conformation of spin centers on the molecular axis are important for the different J values observed in our designed systems.     

Interactions of DNA with graphene and sensing applications of graphene field-effect transistor devices: A review

Graphene field-effect transistors (GFET) have emerged as powerful detection platforms enabled by the advent of chemical vapor deposition (CVD) production of the unique atomically thin 2D material on a large scale. DNA aptamers, short target-specific oligonucleotides, are excellent sensor moieties for GFETs due to their strong affinity to graphene, relatively short chain-length, selectivity, and a high degree of analyte variability. However, the interaction between DNA and graphene is not fully understood, leading to questions about the structure of surface-bound DNA, including the morphology of DNA nanostructures and the nature of the electronic response seen from analyte binding. This review critically evaluates recent insights into the nature of the DNA graphene interaction and its affect on sensor viability for DNA, small molecules, and proteins with respect to previously established sensing methods. We first discuss the sorption of DNA to graphene to introduce the interactions and forces acting in DNA based GFET devices and how these forces can potentially affect the performance of increasingly popular DNA aptamers and even future DNA nanostructures as sensor substrates. Next, we discuss the novel use of GFETs to detect DNA and the underlying electronic phenomena that are typically used as benchmarks for characterizing the analyte response of these devices. Finally, we address the use of DNA aptamers to increase the selectivity of GFET sensors for small molecules and proteins and compare them with other, state of the art, detection methods.     

Recent progress in applications of graphene oxide for gas sensing: A review

This paper is a review of the recent progress on gas sensors using graphene oxide (GO). GO is not a new material but its unique features have recently been of interest for gas sensing applications, and not just as an intermediate for reduced graphene oxide (RGO). Graphene and RGO have been well known gas-sensing materials, but GO is also an attractive sensing material that has been well studied these last few years. The functional groups on GO nanosheets play important roles in adsorbing gas molecules, and the electric or optical properties of GO materials change with exposure to certain gases. Addition of metal nanoparticles and metal oxide nanocomposites is an effective way to make GO materials selective and sensitive to analyte gases. In this paper, several applications of GO based sensors are summarized for detection of water vapor, NO₂, H₂, NH₃, H₂S, and organic vapors. Also binding energies of gas molecules onto graphene and the oxygenous functional groups are summarized, and problems and possible solutions are discussed for the GO-based gas sensors.     

二苯胺取代吖啶衍生物发光材料的合成、表征及电致发光性能

设计合成了2个苯胺取代吖啶衍生物N3,N3,N6,N6-四苯基吖啶基-3,6-二胺(1)和N3,N3,N6,N6-四对甲苯基吖啶基-3,6-二胺(2),通过化学修饰在吖啶核的两端引入二苯胺取代基可以调节化合物的能级和堆积结构等性质,从而使这些吖啶衍生物具有良好的发光性能,可用于制备电致发光器件.基于吖啶衍生物为掺杂发光材料制备的电致发光器件均呈现绿光发射,器件开启电压较低(2.4 V),以化合物1和2制备的器件最高功率效率分别为4.9和8.2 lm/W.考察了其光物理、电化学、热学和荧光量子效率等性能.结果表明,化合物1和2具有较高的量子效率及匹配的能级结构,这是获得较高电致发光效率的基础.     

纳米通道单分子检测低噪音电流放大器系统的研究

研制了一种新型微电流放大器系统,用于检测琢-Hemolysin生物蛋白纳米通道在单分子检测实验中所产生的微弱电流信号(<100 pA)。在1 mol/L KCl、10 mmol/L Tris-HCl,1 mmol/L EDTA的缓冲液(pH 8.0)中测定了DNA-PEG-DNA交联物与纳米通道的穿越和碰撞信号。实验中使用3 kHz贝塞尔滤波器和100 kHz模数转换器来对电流进行采样。结果表明,此放大器系统能够有效降低电流记录过程中的噪音,有利于分辨待测物分子与纳米通道作用所产生的较小阻断的电流信号(<10 pA)。     

Lanthanide Complexes with Multidentate Oxime Ligands as Single‐Molecule Magnets and Atmospheric Carbon Dioxide Fixation Systems

The synthesis, structure, and magnetic properties of five lanthanide complexes with multidentate oxime ligands are described. Complexes 1 and 2 ( 1 : [La₂(pop)₂(acac)₄(CH₃OH)], 2 : [Dy₂(pop)(acac)₅]) are synthesized from the 2‐hydroxyimino‐N‐[1‐(2‐pyridyl)ethylidene]propanohydrazone (Hpop) ligand, while 3 , 4 , and 5 ( 3 : [Dy₂(naphthsaoH)₂(acac)₄H(OH)]?0.85 CH₃CN?1.58 H₂O; 4 : [Tb₂(naphthsaoH)₂(acac)₄H(OH)]?0.52 CH₃CN?1.71 H₂O; 5 : [La₆(CO₃)₂(naphthsao)₅ (naphthsaoH)_0.5(acac)₈(CO₃)_0.5(CH₃OH)_2.76H_5.5(H₂O)_1.24]?2.39 CH₃CN?0.12 H₂O) contain 1‐(1‐hydroxynaphthalen‐2‐yl)‐ethanone oxime (naphthsaoH₂). In 1 – 4 , dinuclear [Ln₂] complexes crystallize, whereas hexanuclear La^III complex 5 is formed after fixation of atmospheric carbon dioxide. Dy^III‐based complexes 2 and 3 display single‐molecule‐magnet properties with energy barriers of 27 and 98 K, respectively. The presence of a broad and unsymmetrical relaxation mode observed in the ac susceptibility data for 3 suggest two different dynamics of the magnetization which might be a consequence of independent relaxation processes of the two different Dy³⁺ ions.     

Strong Direct Magnetic Coupling in a Dinuclear CoII Tetrazine Radical Single‐Molecule Magnet

The ligand‐centered radical complex [(CoTPMA)₂‐μ‐bmtz^.?](O₃SCF₃)₃ ? CH₃CN (bmtz=3,6‐bis(2′‐pyrimidyl)‐1,2,4,5‐tetrazine, TPMA=tris‐(2‐pyridylmethyl)amine) has been synthesized from the neutral bmtz precursor. Single‐crystal X‐ray diffraction studies have confirmed the presence of the ligand‐centered radical. The Co^II complex exhibits slow paramagnetic relaxation in an applied DC field with a barrier to spin reversal of 39 K. This behavior is a result of strong antiferromagnetic metal–radical coupling combined with positive axial and strong rhombic anisotropic contributions from the Co^II ions.     

基于制备接枝型分子印迹膜构建农药电位型电化学传感器及其检测性能研究

基于分子设计,以氯甲基化聚砜(CMPSF)为基膜,阴离子单体对苯乙烯磺酸钠(SSS)为功能单体,N,N'-亚甲基双丙烯酰胺(MBA)为交联剂,在表面引发体系-NH2/S2O2-8的作用下,采用"接枝聚合与分子印迹同步进行"的分子表面印迹新技术,制备了接枝型农药抗蚜威分子印迹膜(MIM)。采用红外光谱(FITR)和光学显微镜(OM)对该分子印迹膜进行表征,通过等温结合实验与竞争吸附实验,考察了抗蚜威分子印迹膜的分子识别性能与机理。以该印迹膜作为敏感膜,构建了抗蚜威电位型传感器,并对其检测性能进行了考察。结果表明,所制备的接枝型印迹膜对模板抗蚜威分子具有特异的识别选择性和优良的结合亲和性,结合容量高达92μg/cm2,相对于分子结构与抗蚜威相似的阿特拉津,印迹膜对抗蚜威的选择性系数为4.537。在p H 4.0的水介质中,传感器膜电极的电位响应与抗蚜威浓度对数在1.0×10-6~1.0×10-3mol/L范围内呈良好的线性关系(r=0.999 9),其检出限为2.5×10-8mol/L;以抗蚜威分子印迹膜为敏感膜所构建的电位型传感器,其构建过程简捷,检测灵敏准确,电位响应快速(t10 s)。