双长链烷基Dawson结构钼磷酸复合薄膜的制备、结构及光致变色性质

近年来 ,无机 -有机复合材料由于其独特的结构和特殊的光、电和磁功能特性而引起科研工作者的广泛关注 [1,2 ] .杂多化合物为均一的无机多聚物 ,具有笼状结构 ,结构中均有 M3O13三金属氧簇 ,能够接受电子生成杂多蓝或杂多棕 ,加之其在水和有机溶剂中的溶解性和稳定性 ,使其在光电变色材料领域中具有潜在的应用价值 [3～ 5] .但这类化合物难于加工成实际应用的器件 ,因而限制了其进一步的应用 .利用有机组分调控的超分子自组装技术可构建光致变色同多酸或杂多酸纳米薄膜材料 ,从而为开发变色响应快、稳定性好、变色可调控的新型光电变色高密…     

含对硝基偶氮苯基团的侧链液晶高分子的合成及其光致变色性能研究

报道了新型的含对硝基偶氮苯基团的甲基丙烯酸酯单体与含介晶基团的甲基丙烯酸酯单体的合成及其自由基共聚合．利用１Ｈ ＮＭＲ、ＩＲ、ＵＶ Ｖｉｓ、ＧＰＣ、元素分析、ＤＴＡ及ＰＯＭ等手段对偶氮单体和聚合物进行了结构表征．证明两种单体的共聚合产物为无规共聚物，而且各聚合物在加热过程中均显示出明显的向列相液晶织构．研究了偶氮单体及其与介晶单体的共聚物的氯仿溶液和聚合物薄膜在紫外光诱导下的光异构化及热回复异构化行为．结果表明，它们在紫外光诱导下均能发生光致变色现象，而且介质对其光化学行为起决定作用．     

NMR structural elucidation of photochromic quinolone photoproducts

UV irradiation of 3-benzoyl-2-benzyl-6,7-difluoro-1-propyl-1H-quinolin-4-one leads to the formation of a mixture of photoproducts, with different evolutions. The structure of each of them has been obtained by one- and two-dimensional multinuclear NMR experiments. Two photoenols, which are thermally reversible, have been identified. All of the other photoproducts have been assigned to degradation. Based on the structural identification and the photochemical and thermal evolution of samples, a plausible mechanism is proposed.     

含偶氮苯光学活性侧基聚合物研究进展

综述了含偶氮苯光学活性侧基聚合物近年来的发展概况 ,介绍了多种聚合体系的类型。由于偶氮苯光于活性侧基的存在 ,使得这些聚合物具有光致变色性、非线性光学活性、光学各向异性等光学性能 ,在光信息存储材料、非线性光学材料、液晶材料、光电子器件、生物分子活性光调控、纳米技术等诸多领域都有广泛的应用。     

Preparation of UV curing crosslinked polyviologen film and its photochromic and electrochromic performances

Polyether urethane diacrylate matrix (PEUDA) and acrylate-functional viologen (ACV²⁺) were successfully synthesized and characterized in detail by FTIR and ¹H NMR spectra, respectively. Subsequently, they were used to prepare UV curing crosslinked polyviologen film in combination with 2-hydroxyethyl methacrylate (HEMA), trimethylolpropane ethoxylate triacrylate (TMPTA) and diphenyl (2, 4, 6-trimethylbenzoyl) phosphine oxide (TPO). UV curing approach confined the polyviologen film on ITO electrode, which imparted the film excellent adhesion ability to ITO glass, good solvent resistance, excellent chemical stability, excellent optical and electrochemical properties. The crosslinked PACV²⁺ film exhibited excellent photochromic and electrochromic performances. After UV illumination for 60 s, the crosslinked PACV²⁺ film can swiftly change its color from pale yellow to deep blue, while the optical transmission of crosslinked PACV²⁺ film at 610 nm did not change significantly and still retained about 63.6% after 30 cycles. Simultaneously, the cyclic voltammetry experiment showed the PACV²⁺ film can undergo repeatable electrochemical redox reactions with good reversibility beyond the 10th scan. Furthermore, the electrochromic device composed of the PACV²⁺ film and gel electrolyte film can undergo reversible color change in response to the external voltages of −2.0 V and 2.0 V, respectively, while the contrast of EC device at 610 nm did not change significantly and still retained about 39.5% after 10 cycles. This UV curing approach to preparing viologen-functional film offers a method to preparing large-scale photo- and electrochromic device, which is relatively simple, high productivity, energy saving, and environmental protection.     

Photochromism of new 3,5-position hybrid diarylethene derivatives bearing both thiophene and thiazole moieties

Five new diarylethenes based on a hybrid structure of bis(5-thiazolyl)ethene and bis(3-thienyl)ethene were synthesized, and the structures of the four compounds were determined by single-crystal X-ray diffraction analysis. The properties of these diarylethenes, such as photochromism, fluorescence, and electrochemical properties were investigated in detail. All of these compounds showed good photochromism and fluorescence both in solution and in PMMA films. The electron-donating substituents could effectively increase the cyclization and cycloreversion quantum yields, and the fluorescence emission peaks, whereas the electron-withdrawing groups functionalized an inverse action for these diarylethene derivatives. Cyclic voltammetry revealed that great differences existed amongst the electrochemical behaviors of these compounds. The oxidation potentials and the band gaps of these diarylethenes increased remarkably with the increase in electron-withdrawing ability. All results suggested that the effects of substitution have a significant effect on the photochemical and electrochemical behaviors of these diarylethene derivatives.     

高效率变色WO3多聚体/1,10-DAD自组装薄膜的制备

新型复合材料能够将多种特异性能结合在一种材料上,为未来的光电材料提供了广阔的应用前景[1,2].无机光电致变色材料因其在信息显示、传感器、调光器件和高密度存储等领域有显著的应用前景而倍受人们的关注[3－6].一般常规方法(物理沉积方法和化学沉积方法等)制备的半导体氧化物光电致变色材料存在着结构无定形、变色响应较慢、变色可逆疲劳等问题,限制了其进一步的应用.分子沉积膜（MolecularDeposition）技术[7,8]能有效构建纳米量级上高度有序的介观结构复合材料,能为新型无机变色材料的设计和构建提供技术支持.　　本研究组已成功地…     

Factors Influencing Photochromism of Spiro-Compounds Within Polymeric Matrices

Abstract

Photochromic polymeric materials have been commercialized in ophthalmic lenses, however, there are many other potential uses for this technology. The photochromic transitions are extremely sensitive to environmental conditions, thus offering the potential for modifying the kinetics to suit different applications. There are a significant number of photochromic molecular families, with different characteristics. The spiro-compounds, both spirooxazines and spiropyrans, have received the most attention as they have good coloration properties and spirooxazines also display good fatigue resistance. Consequently this review focuses on the inclusion of these compounds into polymer matrices. In addition we discuss decoloration and coloration behaviors, solvatochromism, mechanism of fatigue, and unusual synthetic approaches.     

Diarylethenes with intramolecular donor-acceptor structures for photo-induced electrochemical change

Diarylethenes with donor-acceptor groups were synthesized to induce electrochemical switching by light. Photoisomerization was induced by 1,2-bis(2-methyl-1-benzo[b]thiophen-3-yl)perfluorocyclopentene (BTF, 1) unit, while the 3,4-ethylenedioxythiophene (T) and nitro (N) groups were directly connected to BTF, to extend π-electron delocalization. Spectral change to a longer wavelength through photochromism was significant in the donor-acceptor structures (6), accompanied by an increase in the molar absorption coefficients, than those of the unsubstituted BTF (1) or the BTF substituted with only acceptor group (2c and 3c). A significant peak shift toward lower redox energy was observed when the molecules were converted from an open isomer to a closed isomer. The plot of the reduction potentials ((E_1/2^red, V vs Ag/AgCl) vs LUMO energy eV) for the diarylethenes indicates that the reduction potential is strongly dependent on the nature of the substituents around the diarylethene unit. When 6 was applied to a photocell of Au/PC/ITO glass, in which PC is the polystyrene containing 6, it became possible to switch the conductivity of the cell through the film by UV-vis irradiation, as estimated by the I-V plot on a photocell. The conductivity of the cell exposed to UV light was three times larger than that of the cell exposed to visible light, and 10 times larger than that of the cell containing 3, indicating the importance of the push-pull structure for π-electron connectivity through the donor-BTF-acceptor.