有机噻吩类衍生物作为电致变色材料

噻吩类衍生物包括聚噻吩衍生物和齐聚噻吩衍生物。本文从有目的地设计、合成噻吩类衍生物的角度出发,探索了其作为电致变色材料的应用,综述了噻吩类衍生物作为电致变色材料的最新研究进展。     

齐聚噻吩衍生物在溶液中的光物理和电化学性质

The photophysical and electrochemical properties of a family of oligothiophene derivatives in solution werestudied.It was found that the cyano and the vinyl group could increase fluorescence yield in solution,while theformyl and carboxyl group could decrease energy gap.With increasing the chain length of thiophene ring,the oxi-dation potential could be decreased.     

低聚噻吩衍生物单体的合成及其聚合物薄膜的电致变色性能

合成了两种低聚噻吩衍生物单体:2,3':4',2'-三噻吩(I3T)和5,5'-二醛基-2,3':4',2'-三噻吩(OHC-I3T-CHO).通过电化学方法对单体I3T和OHC-I3T-CHO进行了聚合,制备了相应的聚噻吩衍生物.研究了聚噻吩衍生物薄膜的电致变色性能.当外加一定电压时,基于单体I3T的聚噻吩衍生物薄膜可以在淡黄色和淡蓝色之间发生可逆的颜色变化,基于单体OHC-I3T-CHO的聚噻吩衍生物薄膜能在红色和墨绿色间发生可逆的颜色变化.     

水溶性共轭聚电解质的制备及在有机电致变色器件中的应用

制备了聚噻吩电解质聚[3-(1'-丙氧基-3'-磺酸)噻吩](PTH-n₃-SO₃H). 以铂线和ITO玻璃作为电极, PTH-n₃-SO₃H的水溶液作为支持电解质, 分别以齐聚噻吩衍生物5,5"'-双醛基-2,2': 5',2": 5",2"'-四噻吩(4T-2CHO)和5,5"'-双氰基-2,2': 5',2": 5",2"'-四噻吩(4T-2CN)薄膜作为电致变色活性层, 组装了有机电致变色器件. 研究了4T-2CHO和4T-2CN的电致变色性能, 同时考察了PTH-n₃-SO₃H水溶液作为支持电解质在有机电致变色器件中的应用. 研究发现, 当进行电化学掺杂和去掺杂时, 4T-2CHO膜发生从黄色到蓝绿色的可逆变化, 4T-2CN膜发生从淡黄色到蓝色的可逆变化. 结果表明, PTH-n₃-SO₃H水溶液可以作为支持电解质用于有机电致变色器件.     

脉冲激光沉积制备氧化铋薄膜的电致变色性质

通过电位阶跃和循环伏安结合现场电感偶合分光光度计(CCD)测量了脉冲激光沉积的四方结构Bi2O3薄膜的电致变色性质. 结果表明, 在波长为630 nm处出现一个明显的吸收峰, Bi2O3薄膜电极的着色时间为30 s. 吸光度-电位谱图表明, 当电位在3.5 - 0.7 V之间变化时, Bi2O3薄膜的颜色可明显地呈现由透明到暗棕色的可逆变化, 重复次数可达50 次, 在630 nm测得的着色效率约为15 cm2·C-1.     

聚噻吩类电致变色材料的研究进展

电致变色材料广泛应用于显示屏、智能窗、国防军事伪装等各方面,得到了人们的广泛关注。本文介绍了聚噻吩及其衍生物的变色机理,综述了聚噻吩、PEDOT、D-A型材料、D-A-D型材料、噻吩共聚物及其有机/无机纳米复合材料的性能及其研究进展,并简要介绍了噻吩类电致变色材料的应用前景,指出合成颜色变化丰富、稳定性和成膜性好、易加工、并有很好导电性能的D-A-D材料、共聚物及其有机/无机纳米复合材料是聚噻吩类电致变色材料发展的主要趋势。     

苯/二联苯为桥的噻吩-吡咯-噻吩结构:分子构型及电致变色性质

A series of multi-branched dithienylpyrrole (SNS) monomers with rigid phenyl (PhSNS) and biphenyl rings (BPhSNS) as bridges were designed and synthesized, and were fabricated to form cross-linked polymers (pPhSNS, pBPhSNS) by electrochemical polymerization. Cyclic voltammetry (CV) results showed that PhSNS and BPhSNS exhibited similar oxidative properties except for one new higher-potential oxidative peak appearing in the curves of PhSNS. Theoretical calculations indicated that it should be attributed to the different steric configuration between the two dithienylpyrrole (SNS) units in PhSNS. One SNS unit possessed a larger twist angle (40.2°) between thiophene and pyrrole rings than the other one (21.2°), which indicated that PhSNS possessed a relatively larger energy gap (~0.4 eV) between HOMO-1 and HOMO than BPhSNS, for which HOMO and HOMO-1 levels were of almost the same energy. However, both PhSNS and BPhSNS showed similar onset oxidation potentials. The CV curves of pPhSNS and pBPhSNS showed that they presented similar oxidative properties, which enabled their corresponding electrochemical polymers to exhibit similar electrochromic properties. The UV-vis spectra of the corresponding polymers showed that both pPhSNS and pBPhSNS possessed similar optical absorption and similar multicolor switching between yellow (-0.8 V), greyish-green (0.9 V) and gray (1.1 V) colors. Besides, pPhSNS and pBPhSNS showed fast switching times of 0.57 s and 0.93 s at 1100 nm, respectively and reasonable contrasts of 46% and 31% at 1100 nm, respectively. These investigations may help understand the relationship between structural configuration and the electrochemistry/electrochromic properties for polymer electrochromic (PEC) materials research.     

低温热处理氧化钨电致变色薄膜的制备与性质

低温热处理氧化钨电致变色薄膜的制备与性质;电致变色;溶胶 凝胶法;聚乙烯醇;氧化钨     

噻吩衍生物的合成及其光学性能研究

以3-溴噻吩为原料,通过格氏试剂卤锂交换,在过渡金属催化下双环侨联、烷基取代,合成一种液态状双烷基-二噻吩衍生物材料,正丁基锂与三溴噻吩投料比为2:1时收率最高,达80%以上。通过紫外-可见吸收光谱和荧光光谱对其光线发射、吸收及理论计算做了系统性研究,循环伏安(CV)实验对分子内电荷转移情况进行了测试。结果表明双烷基噻吩衍生物的紫外吸收与3,3-双噻吩相比表现出较宽的光谱吸收范围优势,荧光光学能隙值及量子产率均优于3,3-双噻吩,推测衍生物中噻吩邻位增加的烷基侧链作为有效供电子基团,与主环体的Π电子体系共轭发生了明显的电子离域现象,使得双烷基噻吩衍生物具有较好的紫外-可见吸收和荧光发射响应。双烷基噻吩衍生物在不同非质子溶剂中出现随溶剂极性增大发生的吸收及发射波长红移现象,推测化合物分子与不同极性溶剂产生了相互作用,且在特定光源激发后分子内平面共轭结构产生了不同程度的偶极矩变化。最后利用伏安特性曲线验证了双烷基噻吩衍生物良好的光反应活性和导电优势,为光电材料进一步研究提供了理论基础。     

多色显示树枝状聚(3, 6-双噻吩咔唑)及其共聚物的电化学和电致变色性能

设计合成了一种新型的基于咔唑单元的树枝状3, 6-双噻吩咔唑衍生物(BTCPh),通过电化学聚合法制备出其均聚物及与3, 4-乙烯二氧噻吩(EDOT)的共聚物薄膜.利用电化学工作站-紫外可见光谱联用装置对两种聚合物的光谱电化学和电致变色(EC)性能进行表征.测试结果表明,均聚物(PBTCPh)薄膜在不同电压下可显示黄、绿、蓝、灰四种颜色;而EDOT单元的引入使共聚物P(BTCPh-EDOT)进一步增加了掺杂态,从而显示出更加丰富的五种颜色(橙、绿、棕绿、蓝、灰).此外,两种聚合物薄膜均具有良好的光学对比度和快速的响应速度,因而使其在智能窗及显示器方面展现了潜在的应用前景.     

Synthesis,Structure and Magnetic Properties of Two Cobalt(II) Dicyanamide (dca) Complexes with Heterocyclic Nitrogen Donors Tetra(2‐pyridyl)pyrazine (tppz) and 2,4,6‐Tri(2‐pyridyl)‐1,3,5‐triazine (tptz): [Co2(tppz)(dca)4]·CH3CN and [Co(tptz)(dca)(H2O)](dca)

Two new transition metal dicyanamide complexes [Co₂(tppz)(dca)₄]·CH₃CN ( 1 ) [tppz=tetra(2‐pyridyl)pyrazine, dca=dicyanamide] and [Co(tptz)(dca)(H₂O)](dca) ( 2 ) [tptz=2,4,6‐tri(2‐pyridyl)‐1,3,5‐triazine] were synthesized and characterized by single crystal X‐ray diffraction analysis. In 1 each cobalt(II) atom is coordinated to three dca anions and one tppz molecule to form a distorted octahedral geometry, the neigbour two cobalt(II) atoms are bridged by one tppz ligand to form a dimer, then the cobalt(II) atoms in each dimer are joined together to form a ladder chain structure. In 2 the coordination geometry around the central metal is also distorted octahedral, each cobalt(II) atom is coordinated by two dca anions, one tptz molecule and one water ligand to form a cationic part, and the cationic part is linked with the free dca anions via the electrostatic attraction to give an infinite chain structure. Magnetic susceptibility measurement in the range of 2–300 K indicates that there are antiferromagnetic couplings between adjacent metal ions in 1 (T>29 K, (=?9.78 K, C=4.92 cm³·K·mol^?1) and ferromagnetic couplings in 2 (T>150 K, (=7.97 K, C=2.59 cm³·K·mol^?1) respectively.     

A New Two‐dimensional Cyano‐bridged Chromium (HI)‐Nickel (II) Bimetallic Assembly with Stair‐like Layers

From the reaction of K₃[Cr(CN)₆] and [NiL](CIO₄)₂ (L= 1,8‐di(hydroxyethyl)‐l, 3, 6, 8, 10, 13‐hexaazacyclotetradecane), an infinite stair‐like layered assembly [NiL]₃ [Cr‐(CN)₆]₂‐6.5H₂O is obtained, in which each hexacyanochromate(III) ion connects three nickel(II) ions using three cis Of groups and the bridging cyanide ligands coordinate to the nickel ion in a trans fashion forming trans‐NiL(N°C)₂ moieties.     

Cadmium(II) three‐dimensional coordination polymers constructed from 1,3,5‐tris(4‐carboxyphenoxy)benzene: synthesis,crystal structure,fluorescence and I2 sorption characterization

Two three‐dimensional (3D) Cd^II coordination polymers, namely poly[[di‐μ‐aqua‐diaquabis{μ₅‐4,4′,4′′‐[benzene‐1,3,5‐triyltris(oxy)]tribenzoato}tricadmium(II)] dihydrate], {[Cd₃(C₂₇H₁₅O₉)₂(H₂O)₄]·2H₂O}_n, (I), and poly[[aqua{μ₆‐4,4′,4′′‐[benzene‐1,3,5‐triyltris(oxy)]tribenzoato}(μ‐formato)[μ‐1,1′‐(1,4‐phenylene)bis(1H‐imidazole)]dicadmium(II)] dihydrate], {[Cd₂(C₂₇H₁₅O₉)(C₁₂H₁₀N₄)(HCOO)(H₂O)]·2H₂O}_n, (II), have been hydrothermally synthesized from the reaction system containing Cd(NO₃)₂·4H₂O and the flexible tripodal ligand 1,3,5‐tris(4‐carboxyphenoxy)benzene (H₃tcpb) via tuning of the auxiliary ligand. Both complexes have been characterized by single‐crystal X‐ray diffraction analysis, elemental analysis, IR spectra, powder X‐ray diffraction and thermogravimetric analysis. Complex (I) is a 3D framework constructed from trinuclear structural units and tcpb^3? ligands in a μ₅‐coordination mode. The central Cd^II atom of the trinuclear unit is located on a crystallographic inversion centre and adopts an octahedral geometry. The metal atoms are bridged by four syn–syn carboxylate groups and two μ₂‐water molecules to form trinuclear [Cd₃(COO)₄(μ₂‐H₂O)₂] secondary building units (SBUs). These SBUs are incorporated into clusters by bridging carboxylate groups to produce pillars along the c axis. The one‐dimensional inorganic pillars are connected by tcpb^3? linkers in a μ₅‐coordination mode, thus forming a 3D network; its topology corresponds to the point symbol (4².6².8²)(4⁴.6²)₂(4⁵.6⁶.8⁴)₂. In contrast to (I), complex (II) is characterized by a 3D framework based on dinuclear cadmium SBUs, i.e. [Cd₂(COO)₃]. The two symmetry‐independent Cd^II ions display different coordinated geometries, namely octahedral [CdN₂O₄] and monocapped octahedral [CdO₇]. The dinuclear SBUs are incorporated into clusters by bridging formate groups to produce pillars along the c axis. These pillars are further bridged either by tcpb^3? ligands into sheets or by 1,4‐bis(imidazol‐1‐yl)benzene ligands into undulating layers, and finally these two‐dimensional surfaces interweave, forming a 3D structure with the point symbol (4.6²)(4⁷.6¹⁴). Compound (II) exhibits reversible I₂ uptake of 56.8 mg g^?1 with apparent changes in the visible colour and the UV–Vis and fluorescence spectra, and therefore may be regarded as a potential reagent for the capture and release of I₂.     

Synthesis,Characterization, and DNA Binding Studies of a Nickel(II) Complex Containing the 1,3‐Bis(1‐propylbenzimidazol‐2‐yl)‐2‐oxapropane

A complex of formula [Ni(pobb)₂](pic)₂, (pobb = 1,3‐bis(1‐propylbenzimidazol‐2‐yl)‐2‐oxapropane, pic = 2,4,6‐trinitrophenol), has been synthesized and structurally characterized by physico‐chemical and spectroscopic methods. The crystals crystallize in the monoclinic system, space group C2/c, a = 25.766(11) Å, b = 14.943(7) Å, c = 19.543(14) Å, α = 90°, β = 129.722(4)°, γ = 90°, Z = 4. The coordination environment around nickel(II) atom can be described as a distorted octahedral geometry. The interactions of the ligand pobb and the nickel (II) complex with calf thymus DNA (CT‐DNA) are investigated by using electronic absorption titration, ethidium bromide‐DNA displacement experiments and viscosity measurements. The experimental evidence indicated the compounds interact with calf thymus DNA through intercalation.     

Cu(II) and Ni(II)‐1,10‐phenanthroline‐ 5,6‐dione‐amino acid ternary complexes exhibiting pH‐sensitive redox properties

Syntheses, and electrochemical properties of two novel complexes, [Cu(phendio)(L ‐Phe)(H₂O)](ClO₄) ·H₂O (1) and [Ni(phendio)(Gly)(H₂O)](ClO₄)·H₂O (2) (where phendio = 1,10‐phenanthroline‐5,6‐dione, L ‐Phe = L ‐phenylalanine, Gly = glycine), are reported. Single‐crystal X‐ray diffraction results of (1) suggest that this complex structure belongs to the orthorhombic crystal system. The electrochemical properties of free phendio and these complexes in phosphate buffer solutions in a pH range between 2 and 9 have been investigated using cyclic voltammetry. The redox potential of these compounds is strongly dependent on the proton concentration in the range of ? 0.3–0.4 V vs SCE (saturated calomel reference electrode). Phendiol reacts by the reduction of the quinone species to the semiquinone anion followed by reduction to the fully reduced dianion. At pH lower than 4 and higher than 4, reduction of phendio proceeds via 2e^?/3H⁺ and 2e^?/2H⁺ processes. For complexes (1) and (2), being modulated by the coordinated amino acid, the reduction of the phendio ligand proceeds via 2e^?/2H⁺ and 2e^?/H⁺ processes, respectively. Copyright © 2006 John Wiley & Sons, Ltd.     

Ferromagnetically coupled heterobinuclear Cu(II)-Ln(III) complexes with N,N′-bis(2-aminoethyl)-oxamido dianion as a bridged ligand

Six novel μ-oxamido heterobinuclear complexes, namely Cu(oxae)Ln(Me₂bpy)₂-(ClO₄)₃ (Ln? La, Nd, Gd, Tb, Ho, Er), where oxae denotes N, N'-bis(2-aminoethyl)oxamido dianion, Me₂bpy is 4,4'-dimethyl-2,2'-bipyridyl, have been synthesized and characterised by elemental analyses, IR, conductivity measurements and electronic spectra. The temperature dependence of the magnetic susceptibility of Cu(oxae)Gd(Me₂bpy)₂(ClO₄)₃ has been measured over the range 4–300 K. The least-squares fit of the experimental susceptibilities yielded J = 1.87 cm^?1. The observed Gd(III)-Cu(II) coupling is ferromagnetic. One plausible mechanism that can cause a ferromagnetic coupling between Gd(III) and Cu(II) is discussed in terms of spin-polarization.     

Construction of (3,8)‐connected three‐dimensional cobalt(II) and copper(II) coordination polymers with 1,3‐bis[(1,2,4‐triazol‐4‐yl)methyl]benzene and benzene‐1,3,5‐tricarboxylate ligands

Coordination polymers (CPs) have been widely studied because of their diverse and adjustable topologies and wide‐ranging applications in luminescence, chemical sensors, magnetism, photocatalysis, gas adsorption and separation. In the present work, two coordination polymers, namely poly[(μ₅‐benzene‐1,3,5‐tricarboxylato‐κ⁶O¹:O^1′:O³:O³:O⁵,O^5′){μ₃‐1,3‐bis[(1,2,4‐triazol‐4‐yl)methyl]benzene‐κ³N:N′:N′′}di‐μ₃‐hydroxido‐dicobalt(II)], [Co₂(C₉H₃O₆)(OH)(C₁₂H₁₂N₆)]_n or [Co₂(btc)(OH)(mtrb)]_n, (1), and poly[[diaquabis(μ₃‐benzene‐1,3,5‐tricarboxylato‐κ³O¹:O³:O⁵)bis{μ₃‐1,3‐bis[(1,2,4‐triazol‐4‐yl)methyl]benzene‐κ³N:N′:N′′}tetra‐μ₃‐hydroxido‐tetracopper(II)] monohydrate], {[Cu₄(C₉H₃O₆)₂(OH)₂(C₁₂H₁₂N₆)₂(H₂O)₂]·H₂O}_n or {[Cu₄(btc)₂(OH)₂(mtrb)₂(H₂O)₂]·H₂O}_n, (2), were synthesized by the hydrothermal method using 1,3‐bis[(1,2,4‐triazol‐4‐yl)methyl]benzene (mtrb) and benzene‐1,3,5‐tricarboxylate (btc^3?). CP (1) exhibits a (3,8)‐coordinated three‐dimensional (3D) network of the 3,8T38 topological type, with a point symbol of {4,5,6}₂{4²·5⁶·6¹⁶·7²·8²}, based on the tetranuclear hydroxide cobalt(II) cluster [Co₄(μ₃‐OH)₂]. CP (2) shows a (3,8)‐coordinated tfz‐d topology, with a point symbol of {4₃}₂{4⁶·6¹⁸·8⁴}, based on the tetranuclear hydroxide copper(II) cluster [Cu₄(μ₃‐OH)₂]. The different (3,8)‐coordinated 3D networks based on tetranuclear hydroxide–metal clusters of (1) and (2) are controlled by the different central metal ions [Co^II for (1) and Cu^II for (2)]. The thermal stabilities and solid‐state optical diffuse‐reflection spectra were measured. The energy band gaps (E_g) obtained for (1) and (2) were 2.72 and 2.29 eV, respectively. CPs (1) and (2) exhibit good photocatalytic degradation of the organic dyes methylene blue (MB) and rhodamine B (RhB) under visible‐light irradiation.     

Theoretical study of magnetic coupling interaction in terephthalato‐bridged Ni(II) binuclear systems

The density functional theory combined with broken‐symmetry approach has been successfully extended into the study of the long‐range weak coupling interaction in a binuclear Ni(II) complex bridged by terephthalate dianion. The calculated magnetic coupling constant (?0.27 cm^?1) is well in agreement with the experimental one (?0.33 cm^?1). The relative magnitude of the energies of different spin states has been obtained. The spin delocalization and spin polarization occur between two Ni(II) ions, based on the analysis of the spin density distribution. Weak antiferromagnetic behavior in such a system may result from the competition between spin delocalization and spin polarization where the former is dominant. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2004     

Synthesis, Crystal Structure and Thermal Stability of (Diacetylacetone)(diimidazole)Nickel(II) Complex

1 INTRODUCTION Acetylacetone is well known as the intermediate product of organic synthesis reaction, which can be used as annexing agent in gasoline, lubricant and desiccant in paint. Also it has been found to possess fungicidal and insecticidal activi…