纳米晶TiO2电极上半菁衍生物光敏染料

合成了具有不同共轭链长度的吡啶盐类及喹啉盐类半菁染料(E)-N-(4-磺酸丁基)-4-[2-(4-N, N-二甲基氨基苯基)乙烯基]吡啶鎓盐(P1)、(E)-N-(4-磺酸丁基)-4-[2-(4-N, N-二甲基氨基苯基)丁二烯基]吡啶鎓盐(P2)、(E)-N-(4-磺酸丁基)-4-[2-(4-N, N-二甲基氨基苯基)乙烯基]喹啉鎓盐(Q1)以及(E)-N-(4-磺酸丁基)-4-[2-(4-N, N-二甲基氨基苯基)丁二烯基]喹啉鎓盐(Q2).研究了它们的光物理性质，并将它们用作TiO2纳米晶电极的光敏化剂引入光电化学电池.与含有乙烯基共轭桥的染料P1和Q1相比，含有丁二烯基共轭桥的染料P2和Q2在甲醇和氯仿中的最大吸收均发生一定程度的红移，而且吸收光谱变宽.这两类染料都能很好地吸附于TiO2电极上.在比较了四个染料的吸收光谱、摩尔消光系数以及在TiO2电极表面的吸附量后，发现Q1具有最好的光电转化性质.     

双偶极半菁染料/多金属氧酸盐自组装膜的制备及其光电转换性质

通过交替吸附多金属氧酸盐K10P2W18Cd4(H2O)2O68(P2W18Cd4)和双偶极半菁染料(H6),制备了一种无机-有机杂化的自组装薄膜(P2W18Cd4/H6)n,通过紫外可见光谱和光电化学对薄膜进行了研究.结果表明,P2W18Cd4/H6自组装多层膜可被均匀沉积,层数可控,薄膜中半菁染料在可见区的吸收发生红移,并且薄膜能产生稳定的、较强的光电信号.研究了偏压、电子给体和电子受体对薄膜光电转换性质的影响.     

Multifunctional Molecular Material Combining Photocurrent Generation and Second-Order Optical Nonlinearity in LB Monolayer Films

ＩｎｔｒｏｄｕｃｔｉｏｎＭｏｌｅｃｕｌａｒｎｏｎｌｉｎｅａｒｏｐｔｉｃｓ (ＮＬＯ)ｈａｓａｔｔｒａｃｔｅｄｉｎ ｃｒｅａｓｉｎｇｉｎｔｅｒｅｓｔｏｖｅｒｔｈｅｐａｓｔｔｅｎｙｅａｒｓ ,ｂｅｃａｕｓｅｏｆｔｈｅｉｒｐｏｔｅｎｔｉａｌａｐｐｌｉｃａｔｉｏｎｓｉｎｖａｒｉｏｕｓｆｉｅｌｄｓｉｎｃｌｕｄｉｎｇｔｅｌｅｃｏｍ ｍｕｎｉｃａｔｉｏｎｓ ,ｏｐｔｉｃａｌｄａｔａｓｔｏｒａｇｅａｎｄｐｒｏｃｅｓｓｉｎｇａｎｄｏｐｔｉ ｃａｌｐｏｗｅｒｌｉｍｉｔａｔｉｏｎ .1,2 Ｉｔｉｓｗｅｌｌｋｎｏｗｎｔｈａｔｔｈｅｐ…     

汞溴红敏化TiO2纳米多孔膜电极的光电化学性质研究

用汞溴红(Mercurochrome)作敏化剂敏化TiO2纳米多孔膜电极,UV-Vis,光电流作用谱和SPS谱表明,该敏化剂能有效地敏化TiO2电极,并且染料聚集体能扩大染料的敏化区间,增加了太阳光的利用效率,对电极施加不同的偏压,测试电极产生的瞬态光电流,研究了偏压对光生电荷转移及复合速率的影响,从不同方向照射电极,对阳极光电流影响显著,结合电化学、光电化学原理对这些现象进行了讨论.     

TiO2纳米晶电极上半菁衍生物分子设计中空间位阻效应的研究

设计合成了具有不同空间位阻的吡啶盐类和喹啉盐类半菁染料(E)-N-(4—磺酸 根丙基)-4-[2-4（4-N，N-二乙基氨基苯基）乙烯基]吡啶鎓盐（EPS），（E）-N-(4- 磺酸根丁基）-4-[2-(4-N,N-二乙氨基苯基）乙烯基]吡啶鎓盐（EPS4）和（E） -N-（4-磺酸根丁基）-4-[2-（4-N，N-二乙基氨基苯基）喹啉鎓盐（EQS4），研究了它们 的光物理性质，并将它们用作TiO2纳米晶电极的光敏化剂引入光电化学电池中。 研究发现:对于吡啶类半菁染料而言，无论是以三个亚甲基或是以四个亚甲基来连接 吸附基团RSO3^-和发色团时，单个的EPS和EPS4分子的光电响应行为一致．但是由于 以三个亚甲基来连接时，与EPS4相比，染料EPS的空间位阻相对较小，有利于其在 多孔膜上的吸附，最终结果是染料EPS对TiO2纳米晶电极的敏化作用好于EPS4．以喹啉 环为受电子基团的染料EQS4与同样含有四个亚甲基的以吡啶环为受电 子基团的EPS4相比，单个EQS4分子的光电响应行为虽然好于EPS4分子，但由于 EQS4分子间的空间位阻较大，影响了它在多孔电极上的吸附，致使其敏化的太阳能 电池的总光电转换效率有所下降．     

Self-Association of Poly

Three amphiphilic azomethine dyes, (E)-N-octadecyl-2-[2-(4-N, N-dimethylaminophenyl)azomethinyl]quinolinium tiodide, (E)-N-octadecyl-4-[2-(4-N, N-dimethylaminophenyl)azomethinyl]quinolinium iodide, and (E)-N-octadecyl-6-[2-(4-N, N-dimethylaminophenyl)azomethinyl]quinolinium iodide, have been prepared by changing different relative positions of electron-accepting groups. They were successfully transferred onto indium-tin oxide slides by the Langmiur-Blodgett (LB) technique. Photoelectrochemical studies on these dyes' LB monolayer-modified ITO electrode were carried out. In 0.5 M KI solution containing 0.05 M I(2), the photocurrent generation quantum yield for these dyes varied from 7.2 to 15.9%, depending on the linking positions. Dependence of the photocurrent on the applied potential and the redox couple suggests that they undergo the photoinduced electron transfer mechanism of photoelectric conversion. Copyright 2000 Academic Press.     

“推拉”型希夫碱染料的光化学和光电化学性质

合成了一种光降解的两亲性希夫碱染料,（Ｅ）－Ｎ－十八烷基－２－「２－（４－Ｎ,Ｎ－二甲基氨基苯基）胺烯基」吡啶碘化物（ＰＮ２）,考察了它的成膜性能,并成功地应用ＬＢ膜技术将其转移到石英基片或ＩＴＯ电极上形成单层膜,对其光化学和光电化学性质的研究表明：它是一个具有二阶非线性光学性质（ＳＨＧ）和光电响应性质（ＰＥＣ）的可降解有机染料,化合物ＰＮ２单层ＬＢ膜的宏观二阶非线性系数Ｘｚｚｚ＾（２）为１４５．     

一种含稀土半菁的二阶非线性光学材料的研究

LB膜技术作为一种重要手段，可以在分子水平上对材料进行组装．有机化合物作为非线性光学材料，由于具有很大的非线性系数、光学响应速度快及光损伤阈值大等优点而受到人们的重视[1]．对于二阶非线性光学材料而言，其发色团分子的非中。心对称结构是其非线性光学信号叠加的必要条件．LB膜技术以其不同的沉积方式，可有效地控制有机分子的排列和取向，形成非中，心对称结构，成为制备高性能二阶非线性光学材料的良好手段．我们首先将疏水性的稀土配阴离子引入非线性光学成膜材料中，由于其体积较大，可以避免对形成LB膜不利的H聚体的生成…     

Photocurrent Generation and Polarity Switching in Electrochemical Cells through Light-induced Excited State Proton Transfer of Photoacids and Photobases**

Light is a common source of energy in sustainable technologies for photocurrent generation. To date, in such light-harvesting applications, the excited electrons generate the photocurrent. Here, we introduce a new mechanism for photocurrent generation that is based on excited state proton transfer (ESPT) of photoacids and photobases that can donate or accept a proton, respectively, but only after excitation. We show that the formed ions following ESPT can either serve as electron donors or acceptors with the electrodes, or modify the kinetics of mass transport across the diffuse layer, both resulting in photocurrent generation. We further show that control of the current polarity is obtained by switching the irradiation between the photoacid and the photobase. Our study represents a new approach in photoelectrochemistry by introducing ESPT processes, which can be further utilized in light-responsive energy production or energy storage.     

敏化染料分子长径比对太阳能电池性能的影响

采用同一系列但分子长径比不同的3种染料:2-氰基-3-[2-[4-{2-[4-N,N-二(4-甲基苯基)氨基苯基]乙烯基}-苯基氨基)-嘧啶-5-取代基]-丙烯酸(MTPA-Pyc)、2-氰基-3-(4-{2-[4-N,N-二(4-甲基苯基)氨基苯基]乙烯基}-苯基)-丙烯酸(MTPAcc)和2-氰基-3-[4-N,N-二(4-甲基苯基)氨基苯基]-丙烯酸(MTPAc),研究了在不同吸附溶剂中3种染料分子在Ti O2上的吸附量和聚集态,探讨了敏化染料分子长径比对染料敏化太阳电池性能的影响.结果表明,MTPAcc具有最合适的分子长径比,其在Ti O2表面的吸附量及应用的光电性能最高;吸附溶剂的极性增大有利于提高染料的吸附量,但也会影响染料分子的聚集态.当以四氢呋喃为吸附溶剂时,MTPAcc在Ti O2表面的吸附量大且不发生聚集,对应的敏化太阳能电池器件在所有结果中表现最好,在490 nm处的单色光光电转化效率(IPCE)极值达到84%,总光电转化效率(η)达到5.72%.     

Multifunctional Langmuir-Blodgett film of an Amphiphilic Benziminazole Styryl Dye

IntroductionA considerable interest has been focused ondesigning organic crystals with multiproperty suchas conductivity,magnetism,and nonlinear opticalresponse[1,2 ] ,but there have been less reports ondesigning multifunctional Langmuir- Blodgett( LB)films[3 ] .In recent years,our group has found thatLB films of some dyes with a donor-π electronbridge- acceptor ( D-π- A ) structure such ashemicyanine dyes exhibit good photoelectricconversion properties besides their well- knownhigh secon…     

Regenerator dependent photoinduced desorption of a dicarboxylated cyanine dye from the surface of single-crystal rutile

A photon-initiated desorption of a dicarboxylated thiacarbocyanine dye from a dye-sensitized semiconducting oxide crystal has been observed when hydroquinone is used as a regenerator. No desorption was found under the same conditions when KI was used as the regenerator. Intermittent illumination experiments suggest that the oxidation products of the hydroquinone regenerator compete for dye adsorption sites. By comparing the photocurrent decay at both the dye monomer sensitization maximum and the dimer sensitization maximum, a rearrangement of monomer into dimer was observed. A kinetic model for the photocurrent decay as a function of desorption time was derived, and the desorption rate constants were obtained by fitting the experimental data to the model.     

Significant efficiency improvement of the black dye-sensitized solar cell through protonation of TiO2 films

This paper describes the influence of acid pretreatment ofTiO2 mesoporous films prior to dye sensitization on the performance of dye-sensitized solar cells based on [(C4H9)4N]3[Ru(Htcterpy)(NCS)3] (tcterpy = 4,4',4"-tricarboxy- 2,2',2"-terpyridine), the so-called black dye. The HCl pretreatment caused an increase in overall efficiency by 8%, with a major contribution from photocurrent improvement. It is speculated, from the analysis of incident photon-to-electron conversion efficiency, UV-vis absorption spectra, redox properties of the dye and TiO2, and the impedance spectra of the dye-sensitized solar cells, that photocurrent enhancement is attributed to the increases in electron injection and/or charge collection efficiency besides the improvement of light harvesting efficiency upon HCl pretreatment. Open-circuit photovoltage (V(oc)) remained almost unchanged in the case of significant positive shift of flat band potential for TiO2 upon HCl pretreatment. The suppression of electron transfer from conduction band electrons to the I3- ions in the electrolyte upon HCl pretreatment, reflected by the increased resistance at the TiO2/dye/electrolyte interface and reduced dark current, resulted in a V(oc) gain, which compensated the V(oc) loss due to the positive shift of the flat band. Using the HCl pretreatment approach, 10.5% of overall efficiency with the black dye was obtained under illumination of simulated AM 1.5 solar light (100 mW cm(-2)) using an antireflection film on the cell surface.     

Novel D − π − A dye sensitizers of polymeric metal complexes based on 8‐hydroxyquinoline and phenylethyl or fluorene units: synthesis,characterization and photovoltaic applications for dye‐sensitized solar cells

Four novel donor ? π‐bridge ? acceptor (D ? π ? A) polymeric metal complexes (P1–P4) based on 8‐hydroxyquinoline metal complexes were synthesized and tested for their performance in dye‐sensitized solar cells (DSSCs). The polymeric metal complexes dyes use alkoxy benzene or alkyl fluorene as the electron donor and C=C as π linker; the 8‐hydroxyquinoline derivative complex part was used as the electron acceptor and diaminomaleonitrile was used as ancillary ligand. The two strongly electron‐withdrawing cyano groups in the polymer structure can provide an efficient charge transport in the intramolecular between donor and acceptor parts. The thermal, photophysical, electrochemical and photovoltaic properties of these copolymers were investigated by TGA, differential scanning calorimetry, cyclic voltammetry and cureent density‐voltage curves, and the results showed that dye containing complex Zn(II) and alkoxy benzene unit benefited the generation of photocurrent and open‐circuit voltages, and a maximum power conversion efficiency of 1.91% (P2) was obtained, with an open‐circuit voltage of 0.71 V, a short‐circuit current density of 4.23 mA cm^?2, and a fill factor of 38.6% under AM1.5G irradiation. The study results also show that the four polymers exhibit good thermal stability, indicating that these polymeric metal complexes are suitable for the fabrication processes of optoelectronic devices. Copyright © 2013 John Wiley & Sons, Ltd.     

Photoelectrochemical competitive DNA hybridization assay using semiconductor quantum dot conjugated oligonucleotides

A competitive DNA hybridization assay based on the photoelectrochemistry of the semiconductor quantum dot-single stranded DNA conjugates (QD-ssDNA) was developed. Hybridization of QD-ssDNA with the capture probe DNA immobilized on the indium–tin oxide electrodes enables photocurrent generation when the electrochemical cell was illuminated with a light source. Upon the competition between QD-ssDNA and single-stranded target DNA, the photocurrent response decreased with the increase in the target DNA concentration. A linear relationship between the photocurrent and the target DNA concentration was obtained (R ² = 0.991). The selectivity of system towards the target DNA was also demonstrated using non-complementary sample.     

The aggregation of the merocyanine dyes, depending of the type of the counterions

Counterions affect on the substructures formation in the case of the merocyanine dye, 1-methyl-4-[2-(4-hydroxyphenyl)ethenyl)]piridinium] hydrogensquarate both in gas and condense phase. Spectroscopically and structural elucidation of these aggregates have been performed, using solid-state conventional and linear-polarized IR-spectroscopy of oriented colloids as a nematic liquid crystal suspension, UV-vis spectroscopy, HPLC tandem ESI mass spectrometry, (1)H and (13)C NMR, TGV and DSC. Quantum chemical DFT calculations have been carried out as well. Experimental and theoretical data are compared with analogous ones of corresponding iodide salt of dye studied.     

Carboxyphenyl metalloporphyrins as photosensitizers of semiconductor film electrodes. A study of the effect of different central metals

Free-base (P), Zn(II) (P(Zn)), Cu(II) (P(Cu)), Pd(II) (P(Pd)), Ni(II) (P(Ni)), and Co(II) (P(Co)) 5-(4-carboxyphenyl)-10,15,20-tris(4-methylphenyl) porphyrins were designed and synthesized to be employed as spectral senzitizers in photoelectrochemical cells. The dyes were studied adsorbed on SnO(2) nanocrystalline semiconductor and also in Langmuir-Blodgett film ITO electrodes in order to disclose the effect of molecular packing on the studied properties. Electron injection yields were obtained by fluorescence quenching analysis comparing with the dyes adsorbed on a SiO(2) nanocrystalline insulator. Back electron-transfer kinetics were measured by using laser flash photolysis. The unmetallized and metallized molecules have different singlet state energies, fluorescence quantum yields, and redox properties. The quantum yields of sensitized photocurrent generation are shown to be highly dependent on the identity of the central metal. It is shown that P(Ni) and P(Co) do not present a photoelectric effect. The other porhyrins present reproducible photocurrent, P(Pd) being the one that gives the highest quantum yield even in closely packet ITO/LB films. Photocurrent quantum yields increase as the dye ground-state oxidation potential becomes more anodic, which is in agreement with the observation, obtained by laser flash photolysis, that back electron-transfer kinetics decrease with the increase in the driving force for the recombination process. This effect could be exploited as a design element in the development of new and better sensitizers for high-efficiency solar cells involving porphyrins and related dyes.     

Photophysical and (photo)electrochemical properties of a coumarin dye

A new coumarin dye, cyano-{5,5-dimethyl-3-[2-(1,1,6,6-tetramethyl-10-oxo-2,3,5,6-tetrahydro-1H,4H,10H-11-oxa-3a-aza-benzo[de]anthracen-9-yl)vinyl]cyclohex-2-enylidene}-acetic acid (NKX-2753), was prepared and characterized with respect to photophysical and electrochemical properties. It was employed as a dye sensitizer in dye-sensitized solar cells and showed efficient photon-to-electron conversion properties. The photocurrent action spectrum exhibited a broad feature with a maximum incident photon-to-electron conversion efficiency (IPCE) of 84% at 540 nm, which is comparable to that for the famous red dye RuL2(NCS)2 (known as N3), where L stands for 2,2'-bipyridyl-4,4'-dicarboxylic acid. The sandwich-type solar cell with NKX-2753, under illumination of full sun (AM1.5, 100 mW cm(-2)), produced 16.1 mA cm(-2) of short-circuit photocurrent, 0.60 V of open-circuit photovoltage, and 0.69 of fill factor, corresponding to 6.7% of overall energy conversion efficiency using 0.1 M LiI, 0.05 M I2, 0.1 M guanidinium thiocyanate, and 0.6 M 1,2-dimethyl-3-n-propyl-imidazolium iodide in dry acetonitrile as redox electrolyte. In comparison with its analogue NKX-2586 (Langmuir 2004, 20, 4205), NKX-2753 with an extra side ring on the alkene chain produced much higher IPCE values at the same conditions. The side ring acted as a spacer to efficiently prevent dye aggregation when adsorbed on the TiO2 surface, resulting in significant improvements of short-circuit photocurrent, open-circuit photovoltage, and fill factor compared with NKX-2586 that aggregated on the TiO2 surface.     

The synthesis of ethyl 2-[(2,2-dibenzoyl)ethenyl]amino-3-dimethyl-aminopropenoate and its application to the synthesis of fused 3-aminopyran-2-ones and 3-aminoazolo- and -azinopyrimidin-4(4H)-ones

Ethyl 2-[(2,2-dibenzoyl)ethenyl]amino-3-dimethylaminopropenoate ( 3 ) was prepared from dibenzoylmethane ( 1 ) in two steps, and used as a reagent for preparation of fused substituted 3-aminopyranones 12–15 in over 90% yield, quinolizin-4-one 16 in over 79% yield, and fused pyrimidin-4-ones 17–19 in 40–50% yield. Deprotection of (2,2-dibenzoyl)ethenyl group with either diethylamine or hydrazine hydrate produced free amino compounds 20, 21 and 22 in 35%, 91% and 71% yield, respectively.     

Spectroscopic and structural elucidation of merocyanine dye 2,5-[1-metyl-4-[2-(4-hydroxyphenyl)ethenyl)]piridinium]-hexane tetraphenylborate aggregation processes

Structural and spectroscopic elucidation of merocyanine dye, 2,5-[1-metyl-4-[2-(4-hydroxyphenyl)ethenyl)]piridinium]-hexane tetraphenylborate, is performed in gas and condense phase by means of solution and solid-state conventional and linear-polarized IR-spectroscopy of oriented colloids in nematic liquid crystal suspension, UV-vis and fluorescence methods, HPLC MS/MS tandem and ESI mass spectrometry, (1)H, (13)C and (1)H-(1)H COSY NMR, TGV and DSC methods. Quantum chemical DFT calculations are performed for structural optimization and spectroscopic properties prediction.