苯偶酰腙类席夫碱的合成及光学性能研究

以苯偶酰、水合肼以及醛类化合物为起始底物,2步反应高产率合成了苯偶酰腙类席夫碱,采用核磁共振氢谱、碳谱及质谱对其结构进行了表征.此外,分别使用紫外光谱法和荧光光谱法研究了pH值对光谱性能的影响,对常见金属离子的识别性能以及溶剂变化对光谱的影响进行了讨论,光谱性能的研究结果表明,该类化合物可以作为光学染料.

Optical and Electrical Properties of Sensitized Polyaniline by Electrochemical Polymerization

To sensitize polyaniline with dyes by electrochemical polymerization, HClO 4 is employed as the dopant and oxidant, and the polyaniline with different sensitive properties is synthesized. The effect of sensitized emeraldine salt on the absorption spectrum is discussed in details. The maximum conductivity of sensitized films reaches 1.22 S/cm, and investigation on dye sensitizing of the polymer reveals that C.I. Direct Blue 71, C.I. Direct Blue 84, C.I. Direct Black 19 and CuPc-(COOH) 4 may enhance the photoconductivity of polyaniline greatly.

Study on Optical Absorption Behavior of Dyestuff in Fabric

Fabric is a kind of turbid materials with strong light scattering, to which the Kubelka-Munk theory can be applied to describe it optical behavior. In this paper, the light absorption coefficients of dyestuff in fabrics are obtained by test and calculation through a special method proposed by the authors. Then the optical behaviours of dyestuff in fabric are studied. Results show that, the absorption coefficient of dye in fabric is non-scalable and exponential to dye concentration in fabric which is totally different from that of the dye in transparent media like water.

Electronic Absorption Spectra of Copper(Ⅱ) Sulphophthalocyanine and Aggregation of the Dye in Aqueous Solution

Aggregation behavior of C.I.Direct Blue 86 was discussed using analyses of its UV-Vis spectra.The experiment results show that the dye molecules are inclined to aggregate in aqueous solution.Even in a very dilute solution of 0.050μmol/L,A618/A659 =1.2398,showing that the dye monomers still coexist with its dimers.The strong aggregation trend may cause dye precipitates at a higher concentration,which is an important factor that should be considered in producing a formula of ink-jet inks containing the dye as a colorant.

Photocatalytic degradation kinetics in Rhodamine B dye degradation with poriferous TiO_2 photocatalyst

A type of poriferous TiO2 material was prepared using cetyl trimethyl ammonium bromide as a template agent and butyl tetra titanate as a precursor. Through studying the photocatalytic kinetic activity of Rhodamine B photocatalytic degradation reaction with a UV-1601PC ultraviolet-visible spectrophotometer, the photocatalytic degradation process of Rhodamine B was found to not correspond to the first-order kinetic process completely. According to the reaction phenomenon, the photocatalytic degradation process of Rhodamine B with poriferous TiO2 involved two irreversible reactions. The kinetic model was tested using experimental data.

Kinetic Modeling of the Photocatalytic Reduction of Cr（VI） in the Presence of Dye Using Composite Photocatalyst

The photocatalytic properties of surface TiO2 supported zeolite in a semi batch reactor for the reduction of Cr（VI） in the presence of methyl orange dye were investigated. The prepared composite photocatalyst was characterized by SEM-EDS （scanning electron microscopy and energy dispersive spectroscopy）. The effects of operating parameters such as the pH and concentration of Cr（VI） in the absence and presence of dye were evaluated. The Cr（VI） reduction was more efficient in the ternary system （Cr（VI）/dye/TiO2-zeolite） than that of the corresponding binary system （Cr（VI）/TiO2-zeolite）. The extent of metal reduction after 210 min of irradiation was 68% at pH = 3 for the ternary system. In order to optimize the effectiveness of the composite photocatalyst on the photocatalytic reduction of Cr（VI）, kinetics and isotherm models were applied. The kinetics of Cr（VI） in the presence of dye on TiO2/zeolite composite photocatalyst followed the pseudo-first-order model while the equilibrium data correlated reasonably well with Freundlich isotherm.

Dye-sensitized photoanode decorated with pyridine additives for efficient solar water oxidation

Splitting water into hydrogen and oxygen by dye-sensitized photoelectrochemical cell(DSPEC)is a promising approach to solar fuels production.In this study,a series of pyridine derivatives as surface additives were modified on a molecular chromophore and water oxidation catalyst co-loaded TiO_(2)photoanode,TiO_(2)|RuP,1(RuP=Ru(4,4′-(PO3H2)2-2,2′-bipyridine)(2,2′-bipyridine)2,1=Ru(bda)(L)2,(bda=2,2′-bipyridine-6,6′-dicarboxylate,L=10-(pyridin-4-yloxy)decyl)phosphonic acid).The addition of pyridine additives was found to result in up to 42%increase in photocurrent.Under simulated sun-light irradiation,TiO_(2)|RuP,1,P1(P1=4-Hydroxypyridine)produced a photocurrent density of 1 mA/cm2 at a bias of 0.4 V vs.NHE in acetate buffer.Moreover,the observed photocurrents are correlated with the electron-donating ability of the substituent groups on pyridine ring.Transient absorption measurements and electrochemical impedance spectroscopy revealed that surface-bound pyridine can effectively retard the back-electron transfer from the TiO_(2)conduction band to the oxidized dye,which is a major process responsible for energy loss in DSPECs.

Aggregation-Induced Emission(AIE)Active Fluoroboronated Pyridylhydrazinyl Aldehyde Hydrozone Dyes:Synthesis,Crystal Structure and Optical Properties

A new family of fluoroboronated pyridylhydrazinyl aldehyde hydrozone fluorophores named BOPAHs were developed via a simple one-pot two-step reaction from chloro-2-hydrazinylpyridine and aromatic aldehyde derivatives.They were well characterized by NMR,HRMS,and X-ray crystal structures.They exhibit main absorption from 400 nm to 600 nm and emission bands from 500 nm to 700 nm.The absorption/emission bands redshift with increased polarity of solvents indicate a distinct intramolecular charge transfer characteristic,further confirmed by density functional theory(DFT)calculations.These BOPAHs display weak fluorescence in solutions,but they exhibit obvious aggregation-induced emission properties,possibly resulting from weak intermolecular interactions by fixing the molecular conformations in aggregate states.

Highly-ordered dye-sensitized TiO_2 nanotube arrays film used for improving photoelectrochemical electrodes

Thin titanium oxide nanotube arrays (TNAs) films were synthesized by anodization of titanium foil in an aqueous dimethyl sulfoxide solution using a platinum foil counter electrode.TNAs up to 6.8 μm in length,120 nm in inner pore diameter,and 20 nm in wall thickness were obtained by 40 V potentials anodization for 24 h.Their microstructures and surface morphologies were characterized by XRD,TEM,SAED and UV-vis spectroscopy.The photoelectrochemical properties of as-prepared unsensitized and dye-sensitized TNAs electrodes were examined under simulated solar light (AM 1.5,100 mW/cm2) illumination.The results showed that the photocurrent of the dye-sensitized TNAs electrodes reached 6.9 mA/cm2,which was 6 times more than that of the dye-sensitized TiO2 nanoparticles (TNPs) electrodes.It implied that the electron transport process and the charge recombination suppression within TNAs electrodes were much more favorable in comparison with that in the TNPs electrodes.Electrodes applying such kind of titania nanotubes will have a potential to further enhance the efficiencies of TNAs-based dye-sensitized solar cells.

Tunable nonlinear optical responses based on host-guest MOF hybrid materials

The realization of tunable nonlinear optical(NLO)responses in a single nano-/micro-structure is extremely important.However,in lack of effective ways to integrate multiple performances,it still faces severe limitations during applications.Herein,we demonstrate a wavelength-dependent NLO micro-structure based on host-guest metal-organic framework(MOF)materials through encapsulating linear dye molecules into periodic one-dimensional(1D)channels.The confinement to non-centrosymmetric polar dye molecules enhances the second-/third-order NLO responses of the hybrid crystals,causing obvious two-photon luminescence(TPL),second harmonic generation(SHG)and third harmonic generation(THG)responses in the as-prepared composites.The highly ordered structures of MOFs impart spatial regulation on the linear dye molecules to realize orientation alignment,resulting in the polarized anisotropy emission.NIR-to-NIR(NIR,near-infrared region)two-photon pumped lasing is realized with the natural whispering gallery mode resonance cavities of MOFs under the excitation of a 1200-nm fs laser.Furthermore,tunable NLO properties such as TPL,SHG and THG are achieved through switching the incident excitation wavelength from 800 to 1500 nm.Such hybrid materials with tunable NLO responses may open a new avenue toward designing multifunctional NLO devices in the future.

Tuning the optical properties of BODIPY dye through Cu(Ⅰ) catalyzed azide-alkyne cycloaddition(CuAAC) reaction

Borondipyrromethenes(BODIPY) are a class of fluorescent dyes whose fluorescence quantum yields are generally high and independent of the solvent.In this paper,we report the synthesis of a new type of BODIPY compound that carries an azido group on the 3-position of the pyrrole core.The azido group quenches the fluorescence of the dye due to its weak electron-donating effect.The fluorescence of the BODIPY dye can be switched on after reacting with alkynes via a Cu(Ⅰ) catalyzed azide-alkyne cycloaddition(CuAAC) reaction.We further demonstrate that this azido-BODIPY compound can be used in the cell imaging applications.

噻唑类化合物应用研究新进展

噻唑环是一类重要的含氮硫杂原子的五元芳杂环,其特殊的结构使得噻唑类化合物在化学、药学、生物学和材料科学等诸多领域具有广阔的应用前景,显示出巨大的开发价值,受到广泛关注.本文结合作者的研究工作,参考国内外近五年文献,系统地综述了噻唑类化合物在医药、农药、材料、生物染色剂和超分子化学领域应用研究进展.

Theoretical studies of the structures and spectroscopic properties of the photoelectrochemical cell ruthenium sensitizers,C101 and J13

A variety of heteroleptic ruthenium sensitizers have been engineered and synthesized because of their higher light-harvesting efficiency and lower charge-recombination possibility than the well known homoleptic N3 dye. As such, a great deal of atten- tion has been focused on sensitizers with the general formula Ru（ancillary-ligand）（anchoring-ligand）（NCS）2, among which important examples are Ru（4,4＇-bis（5-hexylthiophen-2-yl）-2,2＇-bipyridine）（4,4＇-carboxylic acid-4＇-2,2＇-bipyridine）（NCS）2 （C101） and Ru（N-（4-butoxyphenyl）-N-2-pyridinyl-2-pyridinamine）（4,4＇-carboxylic acid-4＇-2,2＇-bipyridine）（NCS）2 （J13）. In order to simulate experimental conditions with different pH values, the photosensitizing processes of these sensitizers pos- sessing different degrees of deprotonation （2I-I, lit to OH） have been explored theoretically in this work. Their ground/excited state geometries, electronic structures and spectroscopic properties are first calculated using density functional theory （DFT） and time-dependent DFT （TDDFT）. The absorption and emission spectra of all the complexes in acetonitrile solution are also predicted at the TDDFT （B3LYP） level. The calculated results show that the ancillary ligand contributes to the molecular or- bital （MO） energy levels and absorption transitions. It is intriguing to observe that the introduction of a thiophene group into the ancillary ligand leads directly to the increased energy of the absorption transitions in the 380-450 nm region. The calcula- tions reveal that although deprotonation destabilizes the overall frontier MOs of the chromophores, it tends to exert a greater influence on the unoccupied orbitals than on the occupied orbitals. Consequently, an obvious blue shift was observed for the absorptions and emissions in going from 21-1, 1H to OH. Finally, the optimal degree of deprotonation for C101 and J13 has al- so been evaluated, which is expected to lead to further improvements in the performance of dye-sensitized solar cells （DSSCs） coated with such sensitizers.