一种新型苝衍生物的凝胶行为

采用离子自组装方法,以苝酐的羧酸盐及阳离子表面活性剂二甲基二十八烷基溴化铵（DOAB）为原料,室温下合成一种新型苝衍生物.借用核磁共振仪（NMR）和傅里叶变换红外光谱仪（FTIR）确定目标产物的化学组成和结构.利用透射电镜（TEM）、X射线衍射仪（XRD）、小角X射线散射仪（SAXS）等表征衍生物的凝胶聚集体形貌及排列结构.结果表明：这种苝衍生物能够在芳香环间的π–π相互作用下,通过自组装过程形成有序排列的聚集体,其在甲苯中的凝胶呈现典型的层状结构,苝环之间的π–π相互作用是其形成凝胶的主要驱动力,相互缠结的烷基链与溶剂之间范德华力促使凝胶结构更加稳定.     

Self-assembly constructed by perylene bisimide derivatives bearing complementary hydrogen-bonding moieties

An intermediate compound 2, 4-bis(laurylamino)-6-(1-(2-aminoethyl)-piperazine)-1, 3, 5-triazine was prepared by stepwise nucleophilic substitution on triazine ring by lauryl amine and subsequently 1-(2-aminoethyl)-piperazine. Then imidization of perylene-3, 4, 9, 10-tetracarboxylic acid dianhydride with 2,4-bis(laurylamino)-6-(1-(2-aminoethyl)-piperazine)-1, 3, 5-triazine was carried out to afford a novel perylene derivative bearing two melamine blocks (S₂) and 1, 6, 7, 12-tetra(4-tert-butyl phenoxy)-perylene-3, 4, 9, 10-tetracarboxylic acid bisimide (S₁). The hydrogen-bonding interactions between S₁ and S₂ were investigated by ¹H NMR spectrum, UV/Vis spectrum and fluorescence spectrum. The influences on the morphologies of S₁·S₂ aggregates were investigated. The results show that well-defined nanofibers with a diameter of about 100 nm can be obtained by self-assembly between S₁ and S₂ only in CH₂Cl₂ solution. Based on these results, guidelines for the molecular design and self-assembly of supramolecular polymer materials are presented. Foundation item: Project(50573019) support by the National Natural Science Foundation of China     

苝四羧酸多联体化合物的合成及其光谱特性研究

本文合成了８个四羧酸多联体化合物;测定了这些化合物的吸收光谱、荧光光谱．研究了由供电子分子键连的多联体分子的光谱特性及其分子体系内稳态荧光猝灭机理．首次从吸收光谱和荧光光谱上分析和考察了四羧酸多联体化合物分子体系内的光致电子转移反应．     

有机半导体苝的DFT理论计算研究

采用密度泛函理论(DFT)方法对苝进行了B3LYP/6-31G水平上的分子结构优化、IR光谱、Raman光谱、THz光谱、UV-Vis光谱、分子前线轨道、分子电子密度、Mulliken电荷等理论计算。研究结果表明:理论计算结果与实验数据吻合得较好,对IR、THz、UV-Vis吸收光谱和Raman散射光谱中的特征峰进行了归属,发现苝的THz光谱有三个特征吸收峰,它们分别位于2.94、5.46和7.77 THz,其中5.46 THz的吸收是最强的,它是由以C4-C1-C11-C16为轴的苝分子面外对称弯曲振动产生的。苝在UV-Vis光波段有三个吸收峰,峰值波长分别位于420.79、328.14及303.80 nm,其中420.79nm的紫外吸收峰最强。前线轨道计算表明苝分子的HOMO与LUMO能量差值为3.077eV,它与用UV-Vis的理论计算能隙2.946eV仅有0.131eV(4.45%)的偏差。     

聚苯砜对苯二甲酰胺/苝系荧光材料复合静电纺膜的制备与表征

聚苯砜对苯二甲酰胺(PSA)纤维在防护领域具有广泛的应用,笔者在其纺丝溶液中引入苝系荧光功能材料POSS-PDI-POSS,通过静电纺制备了PSA纤维膜。研究了助纺剂聚丙烯腈(PAN)、共溶剂氯仿、荧光功能材料的引入对PSA溶液流变、电导率和纺丝成形性能的影响,发现在PAN添加量为3%(w)、氯仿添加量为6%(w)和0.4%(w)的POSS-PDI-POSS时可制备纤维直径集中分布在250～600 nm的纤维膜,该纤维膜可发射550 nm的黄绿色荧光(490 nm光激发)和发射580 nm的红色荧光(530 nm光激发)。     

拉伸PVA膜法中膜的拉伸与分子取向的关系

通过对苝的二向色性电子光谱的解析,讨论了拉伸高分子膜法光谱实验中取向轴面及分子平面的关系     

Nonfullerene Polymer Solar Cells based on a Perylene Monoimide Acceptor with a High Open‐Circuit Voltage of 1.3 V

Nonfullerene polymer solar cells (PSCs) are fabricated with a perylene monoimide‐based n‐type wide‐bandgap organic semiconductor PMI‐F‐PMI as an acceptor and a bithienyl‐benzodithiophene‐based wide‐bandgap copolymer PTZ1 as a donor. The PSCs based on PTZ1:PMI‐F‐PMI (2:1, w/w) with the treatment of a mixed solvent additive of 0.5% N ‐methyl pyrrolidone and 0.5% diphenyl ether demonstrate a very high open‐circuit voltage (V _oc) of 1.3 V with a higher power conversion efficiency (PCE) of 6%. The high V _oc of the PSCs is a result of the high‐lying lowest unoccupied molecular orbital (LUMO) of ?3.42 eV of the PMI‐F‐PMI acceptor and the low‐lying highest occupied molecular orbital (HOMO) of ?5.31 eV of the polymer donor. Very interestingly, the exciton dissociation efficiency in the active layer is quite high, even though the LUMO and HOMO energy differences between the donor and acceptor materials are as small as ≈0.08 and 0.19 eV, respectively. The PCE of 6% is the highest for the PSCs with a V _oc as high as 1.3 V. The results indicate that the active layer based on PTZ1/PMI‐F‐PMI can be used as the front layer in tandem PSCs for achieving high V _oc over 2 V.     

Fluorescent 5-alkynyl-2'-deoxyuridines: high emission efficiency of a conjugated perylene nucleoside in a DNA duplex

Four fluorescent 5-alkynyl-2'-deoxyuridines were studied in DNA oligonucleotides and their duplexes. The fluorescence response to hybridization differs dramatically for nucleosides containing a perylene fluorochrome either conjugated or not conjugated to the nucleobase. The conjugated nucleoside, 5-(perylen-3-ylethynyl)-2'-deoxyuridine, shows enhanced long-wavelength emission in the DNA duplex, in contrast to the blue fluorescence of perylene on a flexible linker (in 5-[(perylen-3-yl)methoxyprop-1-ynyl]-2'-deoxyuridine), which is quenched upon duplex formation.     

含有p-n单元的苝聚酰亚胺的三元共聚及敏化光电池性能研究

设计、合成并表征了含有p-n(供电子-吸电子)单元的苝聚酰亚胺,并研究了其作为敏化电极材料的光电池的性能.产物为非晶态.从电子谱中计算出其能带带宽为2.19eV,用电化学循环伏安法中计算得到其电子亲和势(Ea,最低空轨道能级)为-3.94eV,离子势(IP,最高占据轨道能级的绝对值)为6.13eV,其能级与二氧化钛的能级相匹配,对二氧化钛有较好的敏化作用.光电池的光电流作用谱(IPCE)与紫外电子谱十分相似,来源于相同的分子结构吸收.光电压与光强之间有指数的关系.用苝聚酰亚胺为敏化剂的光电池的光电转换效率为0.9%.     

Achieving a High Fill Factor and Stability in Perylene Diimide–Based Polymer Solar Cells Using the Molecular Lock Effect between 4,4′‐Bipyridine and a Tri(8‐hydroxyquinoline)aluminum(III) Core

Two novel perylene diimide (PDI)–based derivatives, Alq₃‐PDI and Alq₃‐PDI 2, are synthesized by flanking a 3D tri(8‐hydroxyquinoline)aluminum(III) (Alq₃) core with PDI and a helical PDI dimer (PDI2) to construct high‐performance small molecular nonfullerene acceptors (SMAs). The 3D Alq₃ core significantly suppresses the molecular aggregation of the resulting SMAs, leading to a well‐mixed blend with a PTTEA donor polymer and weak phase separation. Compared with Alq₃‐PDI , the extended π‐conjugation of Alq₃‐PDI2 results in higher‐order molecular packing, which improves the absorption and phase separation behavior. Thus, the Alq₃‐PDI2 devices have higher J_sc and FF values and better device performance, which are further enhanced by a small amount of 4,4′‐bipyridine (Bipy) as an additive. The coordination between Bipy and the Alq₃ core promotes molecular packing and phase separation, which lower charge recombination and enhanced charge collection in the resulting devices. Therefore, a largely improved J_sc of 15.74 mA cm^?2 and very high FF of 71.27% are obtained in the Alq₃‐PDI2 devices, resulting in a power conversion efficiency of 9.54%, which is the best value reported for PDI‐based polymer solar cells. The coordination can also serve as a “molecular lock,” which prevents molecular motion and thus improves device stability.