新型双向传输型区域规整噻吩嵌段共聚物的合成与研究

通过McCullough法制备出区域规整的HT3-十二烷基噻吩均聚物（HTP3DDT）及3-十二烷基噻吩-恶二唑嵌段共聚物（HT P3DDT-OXD）。利用NMR、GPC等方法对其结构进行了分析表征，均聚物和共聚物的紫外吸收和荧光发射最大波长分别为：387、326、435和463nm，分别发射出明亮的青光和青绿光。同时采用循环伏安法对其电化学性能进行了测定，发现3-十二烷基噻吩-恶二唑嵌段共聚物在正、负区域分别出现了氧化还原峰对，且负区域的一对氧化还原峰出现在较负的方向，具有较高的电子亲和势（-3．17eV），有利于电子从阴极的注入。结果表明：区域规整的3-十二烷基噻吩-恶二唑二元嵌段共聚物实现了集空穴、电子双向传输为一体的高性能的聚合物光电功能材料的性能要求。     

两种新型D/A型聚噻吩衍生物的合成、定性和光学性能

采用Heck偶联法和三氯化铁氧化还原聚合法合成了两种新型的D/A-PTh衍生物,聚(3-(2-(4叔丁基笨基)-5-(4乙烯苯基)-1,3,4-惡二唑))噻吩(P3OXDT)和聚(3-辛-4-(2-(4-叔丁基笨基)-5-(4-乙烯苯基)-1,3,4-惡二唑))-聚3-辛噻吩(P3O40XDT-P30T)共聚物,它们都...     

聚噁二唑芳亚胺联噻吩的合成及性能

以3,3’-二溴-2,2’-联噻吩和2,5-二(4-氨基苯基)-1,3,4-噁二唑为单体,通过钯催化CAr-N偶联合成了新型功能高分子聚噁二唑芳亚胺联噻吩(POXDIBT)。通过分子模拟、傅里叶变换红外光谱、核磁共振氢谱、热重、紫外可见吸收光谱、荧光光谱等分析技术对聚合物的分子结构、分子链构象、热稳定性及光学性能进行了研究。结果表明,该聚合物呈现锯齿形分子链构象,具有较好的溶解性能,热分解温度Td=323℃,在339nm处具有强吸收,激发波长为340nm时,荧光发射波长为401nm。     

含噁二唑类与咔唑类共聚物的合成与表征

由2-苯基-5-〔甲基丙烯酰胺基取代苯基〕-1,3,4-噁二唑(OXD)与甲基丙烯酸乙基咔唑酯(CzE-MA)两种单体合成了含噁二唑和咔唑基团的无规共聚物。通过红外、核磁、紫外、荧光、热重、差示扫描量热,凝胶渗透色谱对聚合物进行了表征。测试结果表明共聚物有很好的溶解性,均可溶于常用的有机溶剂,如THF,CHCl2,CHCl3等,其分子量在16950～22500之间。有良好的热稳定性和很高的玻璃化转变温度(Tg=190～222℃),最大吸收波长在220～340nm之间,具有良好的荧光性,其荧光发射波长均在372～451nm范围内,是一类蓝紫色荧光聚合物。共聚物随着CzEMA组分的减少和OXD组分的增加,发射波长蓝移,其中以P(OXD8-CzEMA2)的荧光性最好,荧光量子产率高达0.70。     

苯并三氮唑与噻吩交替共聚物的合成及性能研究

以4,7-二溴-2-十二烷基-1,2,3-苯并三氮唑和带不同碳数烷基的3-烷基噻吩格式试剂为单体,通过Ni(Ⅱ)配合物催化法分别合成了带有丁基、辛基和十二烷基侧链的共聚物,并采用FT-IR、1H-NMR对其化学结构进行了表征。所得共聚物的M n分别为0.57×104,0.59×104和0.49×104g/mol,其M w(g/mol)分别为1.25×104,1.24×104和0.96×104g/mol。所得共聚物在CHCl3、THF等溶剂中具有较好的溶解和成膜性。聚合物在CHCl3溶液中的紫外-可见最大吸收波长分别为433,432和415 nm,共聚物在固态薄膜状态下的紫外-可见最大吸收波长与溶液比较约红移8nm。3种共聚物表现出较好的荧光性能。     

噁二唑类电子传输材料的研究进展

1,3,4-噁二唑环是一个具有高电子亲和势和空穴阻挡作用的基团,含该基团的化合物是一类具有发光性能的电子传输材料.本文综述了对含1,3,4-噁二唑环的有机小分子、星状、枝化分子和聚合物的电子传输材料的进展,并且对该类化合物作了简要的展望.     

苯并二噁唑系列聚合物的合成及其光电性能的研究

以4,6-二氨基-1,3-苯二酚盐酸盐为原料,分别与对苯二甲酸、1,4-萘二甲酸、2,6-萘二甲酸、2,5-噻吩二甲酸、4,4’-(1,2-二苯基乙烯)二甲酸、反丁烯二甲酸在多聚磷酸介质中反应,合成了单环的聚(1,4-亚苯基)苯并二噁唑(PBO)、稠环的聚(1,4-亚萘基)苯并二噁唑(1,4-PNBO)和聚(2,6-亚萘基)苯并二噁唑(2,6-PNBO)、杂环的聚(2,5-亚噻吩基)苯并二噁唑(PTBO)、含有两个苯环的聚-4,4’-亚(1,2-二苯乙烯基)苯并二噁唑(4,4’-PDPEBO)和直链烯烃的聚亚乙烯基苯并二噁唑(PBOV)。采用傅立叶红外光谱、元素分析对系列聚合物的结构进行了表征。利用电导率仪和荧光光谱仪,对系列聚合物的结构与性能之间的关系进行了分析。研究结果表明,PBO、1,4-PNBO、2,6-PNBO、4,4’-PDPEBO、PTBO和PBOV电导率依次减小;系列聚合物的荧光发射光谱和激发光谱的形状都相近,聚合物的最大发射峰波长是一致的,其中2,6-PNBO的荧光强度最强。     

[1,3,4]-噁二唑衍生物的固相合成及其线性、非线性光谱性质

用固相法合成了2个噁二唑衍生物类有机化合物:5-(4-叔丁基苯基)-[1,3,4]噁二唑-2-苯乙烯基-4-苯基-二苯胺 (化合物1)与9-乙基-3,6-双{5-(4-叔丁基苯基)-[1,3,4] 噁二唑-2-苯乙烯基}-咔唑 (化合物2),并测定了它们的吸收光谱、单光子荧光光谱和双光子荧光光谱.化合物1和2在二氯甲烷溶液中单光子荧光发射峰分别位于519和476nm.在锁模Nd∶YAG激光器800nm激光照射下,化合物1和2发射出很强的双光子上转换荧光,其最大波长分别在520和485nm.     

聚3-烷基噻吩系列物的合成与表征

采用Fe(III)催化剂合成法合成聚3-丁基噻吩(P3BT)、聚3-己基噻吩(P3HT)和聚3-十二烷基噻吩(P3DDT)。用GPC和1 H-NMR对所合成的聚合物的相对分子质量和结构进行表征,用SEM对所合成的聚合物的表面形貌进行观察,并用紫外-可见吸收光谱和荧光光谱研究3种聚合物氯仿溶液的光学性能。结果表明,用该方法合成的聚合物以非晶态形式存在;具有较高的相对分子质量;在氯仿溶液中,P3BT、P3HT、P3DDT的最大吸收峰分别为:436nm、437nm和430nm,最大发射峰分别为570.0nm、581.2nm和573.8nm。综合分析发现P3HT更适于用做聚合物太阳能电池材料。     

双极型均二苯乙烯发光材料的合成和光电特性

已发现三苯胺基和苯并(噁)唑是优良的有机共轭发光材料电荷传输基团.将三苯胺基作为空穴传输基团和苯并(噁)唑作为电子传输基团引入均二苯乙烯分子中,设计并合成了四个新双极小分子发光物质4-二苯氨基-4‘-(2-苯并(噁)唑)均二苯乙烯.通过光谱分析和元素分析等方法确认了其化学结构.所合成化合物的相关分析结果表明化学结构、取代基效应、溶剂环境等因素对其UV-Vis光谱、荧光光谱、荧光量子产率、电致发光谱和启亮电压都产生一定的影响.     

Third-order nonlinear optical characteristics of bulk film effect on regioregular poly(3-dodecylthiophene) thin films fabricated by the drop-casting method

We report the morphologies and the bulk film effect on regioregular poly(3-dodecylthiophene) [RR-P3DDT] thin films fabricated with different concentrations (0.1, 0.2, 0.4 wt%) by drop-casting method using chloroform as a solvent and fused quartz glass as substrate. The measured thicknesses of the films were 220, 340 and 600 nm. The thin films were characterized by UV–Vis spectra and X-ray diffraction. The surface morphology of the thin film (600 nm) was analyzed using atomic force microscopy. The third order nonlinear susceptibility characteristics of the films were measured using Maker fringes method. These films exhibit efficient THG bulk effect with a maximum χ³ value of 1.41 × 10^?10 esu obtained for 0.4 wt% concentration of RR-P3DDT revealing that this material is potentially suited for fabricating optical limiters.     

Comparative study of the structural, optical and photocatalytic properties of semiconductor metal oxides toward degradation of methylene blue

Indium oxide (In₂O₃), zinc oxide (ZnO), stannic oxide (SnO₂), and titanium dioxide (TiO₂) thin films were prepared on glass substrates using electron beam evaporation. The samples characterized by UV-vis spectroscopy, diffraction ray-X and scanning electron microscopy techniques. The photocatalytic degradation of methylene blue in an aqueous solution, as a model compound, was investigated using different metal oxides in an attempt to compare the decomposition reaction rate. The progress of degradation was monitored using UV-vis spectrophotometry. The effects of various experimental parameters such as initial concentration of methylene blue (5-10 mg/l), pH of the solution (2-8), annealing temperature (250-550 °C), and catalyst nature and its microstructure were systematically studied in order to achieve maximum degradation efficiency. The results obtained were fitted with the Langmuir-Hinshelwood model to study the degradation kinetics and discussed in detail. Nearly complete degradation was obtained at optimal operational parameters including the higher annealing temperature of thin film and the increase in MB solution pH. The degradation with In₂O₃ was more efficient than with SnO₂, ZnO and TiO₂ films.     

Molecular orientation of poly(3-butylthiophene) friction-transferred films

Oriented thin films of regioregular-poly(3-butylthiophene) (P3BT) were prepared by friction transfer method. Molecular orientation of P3BT in the friction-transferred films was investigated with grazing-incidence X-ray diffraction (GIXD), polarized ultraviolet–visible (UV) spectra, and infrared (IR) spectra. Polarized UV spectra showed the polymer backbones were aligned in the friction direction. GIXD measurements suggest that a axis in P3BT film is normal to the substrate, that is, π-stacking direction tends to be parallel to the substrate. This orientation is different from those of friction-transferred poly(3-hexylthiophene) and poly(3-dodecylthiophene).     

Synthesis,characterization, and photochromic behaviors of polythiophene derivatives in the solid state

Novel polythiophene derivatives with azobenzene chromophore side chains, poly[3-(6-((4-phenylazo)phenoxyl)hexyl)thienylacetate] (PATh-6), and the copolymers of 3-(6-((4-phenylazo)phenoxyl)hexyl)thienylacetate with 3-alkylthiophenes including 3-hexylthiophene and 3-dodecylthiophene (COP-66 and COP-612) were synthesized. The structure and the thermal property of these polythiophene derivatives were characterized by NMR, FT-IR, UV–vis, XRD, GPC, MDSC, and TGA. The differences in photochromic features and thermochromic behaviors between homopolymer and copolymers have been comparatively studied. The photochemical control of photoluminescence property was achieved with homopolymer PATh-6 both in solution and in the solid state. However, this photo-induced effect becomes less prominent for copolymers COP-66 and COP-612 due to the lower content of azobenzene chromophore in the side chain of copolymers. The photo-induced photochromic feature of homopolymer PATh-6 might be promising for the development of novel field-responsive materials.     

钙钛矿型氧化物AgTaO_3光催化性质的研究

采用水热法制备钙钛矿型化合物AgTaO_3粉末晶体,采用粉末X-射线、扫描电子显微镜(SEM)和固体紫外漫反射光谱对化合物进行结构和物理性质表征,并采用BET法测定比表面积。通过光催化降解苋菜红实验测定AgTaO_3的光催化性能。Rietveld精修结果表明,化合物AgTaO_3属于正交晶系,空间群为Pcmn。该化合物的光催化性质测试表明,此化合物在室温下具有很高的光催化性质,在紫外光照射下能有效地降解染料苋菜红。     

Characterization and activity of Pd-modified TiO2 catalysts for photocatalytic oxidation of NO in gas phase

Pd-modified TiO(2) prepared by thermal impregnation method was used in this study for photocatalytic oxidation of NO in gas phase. The physico-chemical properties of Pd/TiO(2) catalysts were characterized by X-ray diffraction analysis (XRD), Brunauer-Emmett-Teller measurements (BET), X-ray photoelectron spectrum analysis (XPS), transmission electron microscopy (TEM), high resolution-transmission electron microscopy (HR-TEM), UV-vis diffuse reflectance spectra (UV-vis DRS) and photoluminescence spectra (PL). It was found that Pd dopant existed as PdO particles in as-prepared photocatalysts. The results of PL spectra indicated that the photogenerated electrons and holes were efficiently separated after Pd doping. During in situ XPS study, it was found that the content of hydroxyl groups on the surface of Pd/TiO(2) increased when the catalyst was irradiated by UV light, which could result in the improvement of photocatalytic activity. The activity test showed that the optimum Pd dopant content was 0.05 wt.%. And the maximum conversion of NO was about 72% higher than that of P25 when the initial concentration of NO was 200 ppm, which showed that Pd/TiO(2) photocatalysts could be potentially applied to oxidize higher concentration of NO.     

Time-dependent study of the exfoliation process of carbon nanotubes in aqueous dispersions by using UV-visible spectroscopy

In this paper we demonstrate that the sonication-driven exfoliation of aggregates and bundles of single-wall carbon nanotubes (SWNTs) in an aqueous surfactant solution can be easily monitored by UV-vis spectroscopy. The different stages of the exfoliation process were directly visualized by cryogenic temperature transmission electron microscopy, showing an excellent correspondence with the spectroscopic data: the maximum achievable exfoliation (which does not mean that 100% of the NTs are effectively exfoliated) corresponds to the maximum UV-vis absorbance of the NT solution. Moreover, it has been observed that NTs produced by the arc-discharge technology (Carbolex NTs) require less energy to achieve maximum exfoliation than NTs produced by chemical vapor deposition (HiPCO NTs). This difference is attributed to weaker van der Waals attraction between Carbolex NTs in the bundles and aggregates.     

Preparation of C60(O)n-ZnO nanocomposite under electric furnace and photocatalytic degradation of organic dyes

Zinc oxide (ZnO) nanoparticles were synthesized sonochemically by applying ultrasonic irradiation to a mixed aqueous-alcoholic solution of zinc nitrate with sodium hydroxide at room temperature. The morphology and optical properties of the ZnO nanoparticles were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and UV-vis spectroscopy. The C60(O)n nanoparticles were synthesized by heating a mixture of C60 and 3-chloroperoxybenzoic acid in a benzene solvent under the reflux system. The heated C60(O)n-ZnO nanocomposite was synthesized in an electric furnace at 700 degrees C for two hours. The heated C60(O)n-ZnO nanocomposite was characterized by XRD, SEM, and TEM, and examined as a catalyst in the photocatalytic degradation of organic dyes by UV-vis spectroscopy. The photocatalytic effect of the heated C60(O)n-ZnO nanocomposite was evaluated by a comparison with that of unheated C60(O)n nanoparticles, heated C60(O)n nanoparticles, and unheated C60(O)n-ZnO in organic dyes, such as methylene blue (MB), methyl orange (MO), and rhodamine B (RhB) under ultraviolet light at 365 nm.     

Surface modification and functionalization of electroactive polymer films via grafting of polyelectrolyte,polyampholyte and polymeric acids

Films of electroactive polymers, such as polyaniline (PAN) in its emeraldine base form, and poly(3-alkylthiophene), poly(3-hexylthiophene) (P6TH), poly(3-octylthiophene) (P8TH), and poly(3-dodecylthiophene) (P12TH) can be readily functionalized via thermal or near ultraviolet-light-induced surface graft copolymerization with monomers of polyelectrolyte, polyampholyte and polymeric acids. The monomers used in the present work include dimethyl sulphate quaternized dimethylamino-ethylmethacrylate (DMAEM·C₂H₆SO₄), 3-dimethyl(methacryloyloxyethyl)ammonium propane sulphonate (DMAPS), acrylic acid (AAc) and a sodium salt of styrene sulphonic acid (NaSS). The surface structures and compositions of the electroactive polymer films after functionalization via graft copolymerization were characterized by angle-resolved X-ray photoelectron spectroscopy. Graft copolymerization of poly(3-alkylthiophene) films, but not PAN films, with the hydrophilic monomers readily results in a stratified surface microstructure arising from the migration of the hydrophilic graft chains beneath a thin surface layer which is much richer in the substrate chains. On the other hand, graft copolymerization of PAN films with AAc and NaSS readily gives rise to a self-protonated (and thus conductive) surface structure.     

Interfacial construction of gold nanoshells on 3-aminopropyl triethoxysilane modified ITO electrode surface for studying cytochrome b562 electrochemistry

An interface of gold nanoshells (GNSs) was constructed on the surface of the 3-aminopropyl triethoxysilane (APTES) modified ITO glass substrates by a simple self-assemble method to form the GNSs-coated ITO electrode. UV-vis spectroscopy, scanning electron microscopy (SEM), and cyclic voltammetry were used to characterize the GNSs interface architectures. SEM and UV-vis spectroscopy showed that an interconnected and stable GNSs interface was formed on the APTES modified ITO glass substrate. The cytochrome b562 (Cyt b562) was selected to observe electron transfer reactions of redox protein at the GNSs-coated ITO electrodes. Quasi-reversible electrochemistry of Cyt b562 was obtained and its electrochemical behaviors were discussed.