Synthesis and properties of novel low band-gap polymers bearing squaraine units

Novel main-chain-conjugated poly(carbazol-alt-squaraine) and poly(dipyridyl-alt-squaraine) were successfully synthesized through direct polycondensation of 9-(2-ethylhexyl)carbazole-bridged or dipyridyl-bridged bispyrrole and squaric acid.The structures and properties of the polymers were characterized using ~1H NMR,FT-IR,UV-vis and cyclic voltammetry.Both polymers exhibit excellent solubility in common organic solvents and good thermal stability.Their UV-vis absorption spectra indicated the polymers have b...

Synthesis of Multidentate Squaraines

To search for more better sensitizer of organic solar cell, a series of multidentate squaraines (Sq1~6) were synthesized, the structures were determined by elemental analysis, IR, UV-vis, 1H NMR and MS spectroscopies. The squaraines have good solubility in polar solvents such as EtOH, CH3COCH3, CHCl3,etc. as well as strong absorption band over 600~700 nm spectral range.

Synthesis and characterization of novel low band-gap polymers containing squaraine units

Novel conjugated polymers based on squaric acid having 2,5-Bis[（E）-N-alkylpyrrol-2-ylvinyl]-3-alkylthiophene （PVTVP） unit in the main chain were successfully synthesized in good yields through polycondensation reaction. Their molecular structures were characterized by PT-IR and IH NMR. They have good solubility in common organic solvents, good thermal stability by thermal gravimetric analysis and high molecular weights. Their optical properties were investigated by UV-vis absorption spectra in CH2C12 solution, the results indicated all these compounds showed broad and strong spectral responses from 200 nm to 900 nm, suggesting their potential for application as organic plastic solar cells.

A synergetic strategy of NIR-Ⅱ squaraine dyes with ultrahigh photothermal conversion efficiency for photothermal therapy

Recent research on photothermal therapy(PTT) has sparked significant interest in the development of new organic photothermal agents(PTAs),ranging from single-molecule to aggregated levels.However,controlling aggregation pathways for PTAs with ultrahigh photothermal conversion efficiency(PCE) remains a major challenge.Herein,a two-pronged approach utilizing “Haggregation” and “intramolecular motion” was employed to enhance the PCE of an acceptor-substituted squaraine dye(NSQs).The C2vmolecular symmetry of the NSQs,which possess a ground state dipole moment(μg),promotes H-dimeric aggregates through dipole-dipole counteraction.Peripheral triphenylethylene or diphenylamine groups were added to this H-dimeric nanoplatform.This was done to enhance intramolecular motions for heat generation and also to extend conjugation,which redshifted the optical absorption and balanced the blue-shift induced by H-aggregation.With this technique,an organic PTA with NIR-II absorption was developed,and its nanoparticle achieved a remarkable PCE of 86.3% under 1,064 nm laser excitation.Femtosecond transient absorption spectroscopy and quantum mechanical calculations demonstrated the accelerated internal conversion process in NIR-II PTAs for rapid heat generation.The NSQs nanoparticles exhibit superior photothermal therapeutic properties for in vivo photoacoustic imaging-guided PTT,demonstrating the potential of bottom-up design to enable synergistic engineering strategies towards efficient phototheranostic agents.

自制开放式荧光光谱仪的搭建、性能测试与实际应用

荧光检测在化学分析、生物检测等多个领域得到广泛应用,因此对本科生进行相关实验教学具有重要意义。本实验成功创制了一套价格低廉、体积小巧的开放式荧光光谱仪,对其性能进行全面评估,并成功应用于实际样品的检测。这有助于培养学生的仪器设计和创制意识,增强他们对自主创制仪器的信心。

A squaraine based fluorescent probe for mercury ion via coordination induced deaggregation signaling

Due to the high affinity between dithiocarbamate （DTC） and Hg2＋, a fluorescent probe based on squaraine chromophore with DTC side arm for Hg2＋ via coordination induced deaggregation signaling has been designed and synthesized. Squaraine has a high tendency to aggregate in aqueous solution, and such self-aggregation usually results in a dramatic absorption spectral broadening with fluorescence emission quenching. The combination of the DTC side arm of the probe with Hg2＋ induces steric hindrance, leading to the deaggregation of the dye complex, companying with a fluorescence emission restoration. In EtOH-H2O （20：80, v/v） solution, this ＂turn on＂ fluorescent probe has high selectivity and sensitivity toward Hg2＋ over other metal ions, and the limit of detection for Hg2＋ was estimated as 2.19 × 10^-8 mol/L by 3σ/k.

Influence of thermal annealing-induced molecular aggregation on film properties and photovoltaic performance of bulk heterojunction solar cells based on a squaraine dye

Squaraine （SQ） dyes have been considered as efficient photoactive materials for organic solar cells. In this work, we purposely controlled the molecular aggregation of an SQ dye, 2,4-bis[4-（N,N-dibutylamino）-2-dihydroxyphenyl] SQ （DBSQ- （OH）2） in the DBSQ（OH）2：[6,6]-phenyl-Cel-butyric acid methyl ester （PCBM） blend film by using the thermal annealing method, to study the influence of the molecular aggregation on film properties as well as the photovoltaic performance of DBSQ（OH）2：PCBM-based bulk heterojunction （BHJ） solar cells. Our results demonstrate that thermal annealing may change the aggregation behavior of DBSQ（OH）2 in the DBSQ（OH）2：PCBM film, and thus significantly influence the surface morphology, optical and electrical properties of the blend film, as well as the photovoltaic performance of DBSQ（OH）2：PCBM BHJ cells.

Synthesis and properties of a novel squaraine dye modified by ferrocene

A novel squaraine dye（SQ） modified by ferrocene has been synthesized through（E）-dodecyl-2-ferrocenyl vinyl-1H-pyrrole and squaric acid.The molecular structure of SQ was characterized by ~1H NMR,^（13）C NMR,MS and elemental analysis.SQ is high soluble in common solvents.The maximum absorptions of SQ in different solvents are in the range of 708-734 nm,exhibiting positive solvatochromism with increasing solvent polarity.The optical and electrical properties of SQ indicate that it is a promising electron donor material for bulk-heterojunction organic solar cell.

A novel squaraine dye with squaramide as a scaffold and the colorimetric detection of amine

A novel unsymmetrical squaramide-linked squaraine dye（SQ） has been synthesized through squaramide 3 and semisquaraine 6. The molecular structure of SQ has been characterized by ~1H NMR,IR and MS.Due to the influence of the hydrogen bond and the solvent effect,SQ exhibits unique spectral properties compared with typical squaraine dyes.For its excellent ability of binding primary amine,SQ is a promising receptor of recognizing primary amine.

Mechanism of the interaction of color reagent 1, 3-N, N'-bis-4-(4'-nitro benzenediazo) phenyl squaraine with oxoacid anions

By AM1 method, the interactions between 1, 3-N, N’ -Bis-4-(4’ -nitro benzenediazo) phenyl squaraine (BNBPS) and several oxoacid anions have been studied on the basis of the proposed model. The mechanism of the color reactions is suggested and the answers to the question of whether or not BNBPS colorates with HCO 3 - , CO 3 2- , NO2, NO3 etc. are given. It is theoritically predicted that BNBPS might be used as the color reagent for SO 4 2 .

Synthesis and properties of two novel copolymers based on squaraine and fluorene units for solar cell materials

Two novel copolymers based on squaraine and fluorine units have been synthesized through palladium catalyzed Suzuki coupling reaction and Sonogashira coupling reaction,respectively.The structures and properties of the two copolymers were characterized by FT-IR.NMR,UV-vis absorbance（Abs）,gel permeation chromatography（GPC）,thermal gravimetric analysis （TGA）,differential scanning calorimetry（DSC） and cyclic voltammetry（CV）.The solution absorption spectrums of P_1 and P_2 show two distinct absorption bands,one locates at 300-500 nm and the other at 600-800 nm.The absorption spectrums of P_1 and P_2 in films are broadened obviously and the spectral responses are extended up to 900 nm.Thermal gravimetric analysis demonstrates that the polymers are stable.Cyclic voltammetry experiment shows that the band gaps of the copolymers are 1.65 eV and 1.67 eV. respectively,suggesting their potential for applications as solar cells materials.

Investigation of post-thermal annealing-induced enhancement in photovoltaic performance for squaraine-based organic solar cells

In this work,we have systematically investigated the post-thermal annealing-induced enhancement in photovoltaic performance of a 2,4-bis[4-(N,N-diisobutylamino)-2,6-dihydroxyphenyl]squaraine(DIBSQ)/C60 planar heterojunction(PHJ)organic solar cells(OSCs).An increased power conversion efficiency(PCE)of 3.28%has been realized from a DIBSQ/C60 device with thermal annealing at 100°C for 4 min,which is about 33%enhancement compared with that of the as-cast device.The improvement of the device performance may be mainly ascribed to the crystallinity of the DIBSQ film with post-thermal annealing,which will change the DIBSQ donor and C60 acceptor interface from^PHJ to hybrid planar-mixed heterojunction.This new donor-acceptor heterojunction structure will significantly improve the charge separation and charge collection efficiency,as well as the open circuit voltage(Voc)of the device,leading to an enhanced PCE.This work provides an effective strategy to improve the photovoltaic performance of SQ-based OSCs.

基于氨基苯酚类方酸菁的比色荧光探针制备及其在不同溶剂下检测Cu^(2+)和Mg^(2+)性能研究

设计并合成了一种N,N-二丁基-3-氨基苯酚方酸菁染料(ZXSQ),并通过核磁氢谱和高分辨质谱对其结构进行表征。该探针可以在乙腈为溶剂的条件下识别Cu^(2+),颜色由蓝色变为无色;探针在乙醇为溶剂的条件下识别Mg^(2+),颜色泛出强烈的红色荧光。该探针解决了在Cu^(2+)和Mg^(2+)同时存在下无法区别的问题,实现了双识别且抗干扰的效果。该探针检测限均在10^(-6)mol/L,具有合成简单、低检测限和高灵敏度等优点,操作简便,能够快速、精准地检测环境以及生物体中的Cu^(2+)和Mg^(2+)。

三氢-苯并吲哚啉方酸染料晶体中电荷转移过程的理论研究

由于具有良好的光化学稳定性、在可见光区和近红外区的强吸光性等优点,方酸类染料是目前最具潜力的小分子有机太阳能电池给体材料之一.然而,其空穴迁移机制并不明确,较低的迁移率限制了器件光电转换效率的提升.结合第一性原理计算、Marcus电子转移理论、主方程模拟,系统研究了三氢-苯并吲哚啉方酸(USQ-BI)染料的电子结构、分子堆积模式以及电荷转移性质.结果表明,由于空穴迁移路径上交替出现两种不同的分子堆积模式,驱动力呈现正负交错的特征,克服正驱动力的过程为空穴迁移的决速步.据此,提出了降低驱动力绝对值以增大迁移率的理论策略.进一步研究发现,在一些位点上引入氰基可以显著提高空穴转移耦合强度,从而提高空穴迁移率.最后,对USQ-BI中电子转移过程的研究发现,由于较大的重组能导致较小的电子转移速率,该晶体不能作为好的电子传输材料.

方酸菁光敏剂在肿瘤光热治疗领域的应用

光热治疗由于具有高选择性、非侵入性、低损伤等优点成为了一种新型的微创癌症治疗手段,它主要利用光热剂(又称光敏剂)在光照条件下将光能转化为热能来杀死癌细胞,其中光热剂是决定光热治疗效果的关键因素之一。方酸菁染料是一类由两个富电子单元和一个强吸电子方酸核单元缩合形成的共轭有机分子,具有共振稳定的两性离子结构。方酸菁在可见及近红外区有强烈吸收和发射性能,其摩尔消光系数(ε)高达105 L/mol·cm;其次,方酸菁还具有易聚集、合成路线简单、光/热稳定性好、结构修饰性强等优点。因此,方酸菁染料用作光热治疗光敏剂具有巨大的潜力,本文就近年来方酸菁染料在肿瘤光热治疗领域的应用研究进展做一综述,以供临床参考借鉴。

一种方酸菁染料探针用于人血清白蛋白的检测

人血清白蛋白(HSA)是人体的主要蛋白质之一,具有重要的生理功能,因此,对HSA的准确测定具有重要的应用价值。本文合成了一种近红外方酸菁染料(YSQ)探针用于检测人血清白蛋白。探针YSQ自身的荧光较弱,但加入HSA后荧光强度显著提高,基于此原理建立了人血清白蛋白的检测方法。人血清白蛋白在浓度为10~300 mg/L范围时,与荧光强度具有良好的线性响应范围,检出限(S/N=3)低至0.88 mg/L,响应迅速(<1 min)。竞争性试剂布洛芬加入后,荧光强度显著降低,说明探针可能作用于HSA的结合位点Ⅱ。将此探针用于检测尿液中HSA的含量,回收率在89.4%~111.2%之间,表明该方法具有良好的实用性。

Anisotropy in Third-Order Nonlinear Optical Susceptibility of a Squarylium Dye in a Nematic Liquid Crystal

A squarylium dye is dissolved in 4-cyano-4＇-pentylbiphenyl （SCB） and oriented by sandwiching mixtures between two pieces of rubbed glass plates. The optical absorption spectra of the oriented squarylium dye-5CB layers exhibit high anisotropy. The third-order nonlinear optical responses and susceptibilities X^（3）e of squarylium dye in 5CB are measured with light polarizations parallel and perpendicular to the orientational direction by the resonant femtosecond degenerate four-wave mixing （DFWM） technique. Temporal profiles of the DFWM signal of the oriented squarylium dye-5CB layers with light polarizations parallel and perpendicular to the orientational direction are measured with a time resolution of 0.3ps （FWHM）, and are found to consist of two components, i.e., the coherent instantaneous nonlinear response and slow response due to the formation of excited molecules. A high anisotropic ratio of x^（3）e, 10.8 ：k 1.2, is observed for the oriented layers.

1,3-方酸衍生物亲电作用的理论研究

设计了负离子与２，４－二苯基－１，３－环丁烯二酮（Ｓｑ）的作用模型，用ＡＭ１方法研究了Ｆ－，Ｃｌ－，Ｂｒ－，Ｏ２－，Ｓ２－等负离子与Ｓｑ的相互作用．结果表明，负离子对体系具有稳定化作用，离子电荷。

六元环硼氮烷对称取代方酸的电子光谱和非线性光学性质的DFT研究

用量子化学密度泛函理论 B3 LYP方法 ,在 6-3 1 G( d)水平上对环硼氮烷和苯基对称取代方酸进行几何构型优化 .以此为基础 ,利用 TD-DFT方法得到方酸衍生物的 UV-Vis吸收光谱 .进一步引入外电场 ,用有限场 ( FF/ DFT-B3 LYP)方法探讨了各体系的三阶非线性光学性质 ( NLO) .计算结果显示 ,对称环硼氮烷取代的方酸衍生物性质不同于苯环取代 ,取代位置对电荷分布、分子轨道特征和非线性光学性质的影响很大 .氮原子与方酸相连时对提高方酸体系的三阶非线性光学性质十分有效 ,其 NLO系数可达 2 .3 80 8×1 0 -2 4C·m.

AM1-MO理论对方酸染料结构和电子性质的研究

通过对一系列具有C－5取代基的吲哚方酸菁染料的AM1分子轨道计算，研究了染料结构和基态与单线激发态电子特性，并用（＋）（-）sparkles模拟溶剂化作用，通过AM1－CI计算的染料吸收波长接近实际测量值，并通过基态与单线激发态原子电荷密度的变化，讨论取代基效应对吸收波长的影响；循环伏安法测量的染料有两个可逆的氧化电位，电位数值随取代基给电子性的增加而减小．第一氧化电位与AM1计算的染料离子电离势，用测量的跃迁能校正的电子亲和能与AM1计算值均有很好的线性关系．