溶胶-凝胶法制备无机基质/有机杂化光学材料及其光学性能研究

探索一种制备无机基质/有机杂化光功能材料的途径,采用溶胶-凝胶法在无机基质溶胶中分别掺杂自制的5种有机发光材料,制备出透明、均匀的有机-无机杂化发光薄膜,研究其发光行为,探讨发光行为的规律。     

溶胶-凝胶法制备防腐耐磨杂化涂层的研究进展

有机无机杂化涂层兼有机涂层和无机涂层的双重特点和性能,具有优良的机械性能和阻隔作用,成为材料防护涂层研究的热点。阐述了溶胶-凝胶法合成有机/无机杂化涂层材料的原理和步骤,介绍了有机/无机杂化涂层在材料防腐耐磨方面的研究现状,提出了利用溶胶-凝胶法制备防腐耐磨杂化涂层存在的一些问题。     

脉冲激光法制备修饰纳米(ZnO-Eu_2O_3)/聚苯胺杂化薄膜材料

采用聚焦脉冲激光法(PLA-IT/SFL)制备修饰纳米(ZnO-Eu2O3)/聚苯胺有机溶胶及其杂化薄膜材料。TEM显示金属氧化物粒子粒径约为15nm且其在聚苯胺中有较高的稳定性。荧光光谱表明该杂化薄膜材料在紫外光照射下发出强烈的黄光。热分析表明该杂化薄膜比导电性聚苯胺(PAN-HCSA)薄膜具有更好的热稳定性。该杂化薄膜材料可望用于电致发光领域。     

溶胶-凝胶技术在有机／无机杂化材料制备中的应用

应用溶胶-凝胶法制备有机／无机杂化材料,可根据前驱体的种类和制备方法等对材料微观结构进行裁剪和优化,并可实现材料的功能化。有机／无机杂化材料根据有机相和无机相的比例不同,可分为有机改性陶瓷型杂化材料和陶瓷改性有机物型杂化材料两类。本文综述了应用溶胶-凝胶技术制备有机／无机杂化材料的原理以及应用进展。     

PDMS-BG-TiO2有机无机生物杂化材料的制备和性能研究

具有良好生物活性的有机无机杂化材料已成为生物材料科学领域的重点研究内容.本题目以聚二甲基硅氧烷(PDMS)为改性剂,采用溶胶-凝胶法制备基于生物活性玻璃(PDMS-BG)的有机-无机杂化生物活性材料(PDMS-BG-TiO2),研究了加入不同配比的正硅酸乙酯(TEOS)与异丙醇钛溶液(TIPT)对有机无机杂化材料成型能力和生物活性的影响.研究表明:与未在体液培养的试样相比,将试样在模拟体液SBF培养3d后,由试样的SEM图、XRD图和FHR图谱可得这些材料均具有较好的生物矿化能力,当正硅酸乙酯∶异丙醇钛为12∶1时,制备的薄膜材料不易发生断裂,并且生物矿化能力表现得更为突出.这种有机无机杂化生物活性材料(PDMS-BG-TiO2)可能用做骨替代或者骨修复等生物材料.     

溶胶—凝胶法制备有机—无机杂化纳米级功能材料

概要总结了溶胶－凝胶法制备有机－无机杂化功能材料的一些制备方法，说明了溶液－凝胶法中存在的问题，并好解决这些问题的研究。     

紫外光固化块体PMMA/SiO2有机/无机杂化材料

以正硅酸乙酯(TEOS)、甲基丙烯酸甲酯(MMA)为原料,采用溶胶-凝胶法和紫外光固化技术制备块体PMMA/SiO2有机/无机杂化材料,通过透射电镜(TEM)、红外光谱(FTIR)和差热分析(DSC)研究了杂化材料的微观特性和热性能,研究表明该方法制备的二氧化硅溶胶粒径在100nm左右,分散良好;杂化材料中有机相和无机相是以共价键的形式相互连接的,没有出现有机相和无机相的相分离现象,并且两相之间形成了互穿的网络结构。     

MCM-41介孔分子筛负载咔唑类荧光分子杂化材料的合成及发光性质

通过浸渍法将5种咔唑类荧光分子负载于介孔材料MCM-41上,制备有机-无机杂化复合荧光材料,并对咔唑荧光分子和杂化复合材料的表面结构、紫外-可见吸收、荧光发射等性质进行了对比。结果表明,负载后的咔唑类荧光分子分散于MCM-41孔道上,材料热稳定性提高,在100~350℃内没有明显失重,其紫外吸收和荧光发射也发生明显蓝移(λmaxabs=331~368 nm,λmaxem=401~435 nm)。制备的杂化复合材料可用作蓝色荧光材料(λmaxem=401~435 nm)。     

ASD/SiO2-TiO2有机 /无机二阶非线性光学杂化材料的研究

利用溶胶－凝胶法合成了一种新型的稳定的有机/无机二阶非线性光学杂化材料，研究了其组成相区和有机生色团在成膜后的取向稳定性。     

有机-无机杂化节能薄膜的制备、性能及应用

通过在有机相中掺杂SiO_2、TiO_2等具有光学性能的无机组分,制备的高紫外光吸收率、高可见光透过率、高红外反射率的有机-无机杂化薄膜可作为玻璃贴膜使用,广泛应用于公用建筑、民用建筑、汽车玻璃等领域,能阻隔50%～78%的热量,节能效果显著.本文介绍了有机-无机杂化节能薄膜的几种制备工艺,包括直接混合法、溶胶-凝胶法、插层复合法、气相沉积法等,比较了其制备工艺条件,分析了各自的优缺点,并对杂化节能薄膜的应用前景进行了展望.     

掺偶氮苯二氧化钛基复合薄膜的制备及光开关性能

通过低温溶胶-凝胶技术结合旋涂法制备了掺偶氮苯二氧化钛基有机-无机复合薄膜。研究了不同热处理温度对复合薄膜的表面形貌、传输模式、折射率与厚度和光化学结构特性的影响。结果表明:该复合薄膜在低于300℃的热处理温度时表面光滑致密、折射率可调,是良好的光波导材料。通过测试样品在365 nm紫外光和450 nm可见光照射下的吸光度,研究了复合薄膜的光开关性能。在研究周期内,光开关性能良好,具有一定的抗疲劳性,在光电子学领域具有重要的应用价值。     

作物转光喷施液的制备及性能研究

将CaS：Eu荧光粉添加到高分子溶液中配成转光液,喷涂后自然条件下干燥成膜。探讨了分散方法对转光液所成薄膜光学性能的影响,确定了较优的分散方法;测试了薄膜的荧光光谱、透光率、荧光抗衰减性能。结果表明,转光液可在植物叶面上快速成膜,薄膜具有吸收紫外光和绿光发射645nm红光的作用,转光行为能促进植物光合作用,薄膜可见光区的透光率在70％以上,荧光抗衰减性能较好,这种转光喷施液是一种没有污染而十分有效的“光肥”。     

Super black and ultrathin amorphous carbon film inspired by anti-reflection architecture in butterfly wing

An ultrathin and super black amorphous carbon (a-C) film has been fabricated by borrowing the inverse V-type anti-reflection nano-architecture from the black wings of butterfly Ornithoptera goliath through vacuum sintering process. The biomimetic a-C film shows good optical absorption (99%) at low reflectance (<1%) in visible light (380–795 nm), which is comparable to the previously fabricated darkest materials, while with a thickness (5 μm) of only 15% of those materials. Experimental results as well as theoretical simulation which is based on finite difference time domain method (FDTD) show that reflection of the fabricated inverse V-type structured a-C film is merely 1/13 of that of the flat surface a-C film, and 1/8 of that of glassy carbon. Complex refractive index of the derived a-C for visible light (380–795 nm) has also been calculated.     

EVA/铕配合物薄膜的制备及光学性能研究

通过溶液浇铸法将四元铕配合物掺杂到乙烯醋酸乙烯酯（EVA）中交联固化得到EVA复合膜,优化了制备EVA膜时固化温度、固化时间和引发剂加入量等工艺条件。通过紫外可见光光谱、荧光光谱研究了EVA复合膜的光学性能。结果表明,配合物在EVA中均匀分散;其掺杂量为1 %时,EVA复合膜具有良好的可见光透过率,对200~400 nm的紫外光有强吸收,并且能够发射出较强的红色荧光。     

Rheological measurements of cure rate of UV inks

The dynamic viscosity of UV inks during curing was measured at various film thickness using an oscillating plate rheometer. Logarithmic plots of the dynamic viscosity versus exposure energy are closely related by two-straight lines. A useful concept in discussing the curability is the minimum exposure energy difined as the exposure energy at the intersection of two lines. On exposure to a monochromatic light of 365 nm, the minimum exposure energy increases exponentially with film thickness; this resulting from an exponential decay of the light intensity with depth in the film. Magenta ink shows the fatest cure rate at a given thickness, followed by yellow, cyan, and black inks in that order. The difference in cure rate is attributed to different absorbances of pigments. The UV curability on direct exposure to UV lamp is predicted from the spectral sensitivity of the photoinitiator and the viscosity data obtained during curing under 365 nm light. The model calculation shows good agreement with the experimental results.     

二氧化钛光催化降解处理水溶性甲醛的研究

以TiO2为光催化剂,在自制光催化反应器中研究了紫外光源对甲醛废水进行光催化降解的可行性。结果表明,甲醛浓度在40 mg/L,其最佳工艺条件为:反应pH为7,TiO2锐钛矿与金红石晶型比为1∶1,5 g/L的TiO2催化剂投加量,采用λ=350~400 nm紫外灯作为光源。同时,TiO2催化剂有较好的回收利用性能。     

Electrospinning of biopolymer nanofibers encapsulated with functional nanoparticles toward core-shell fluorescence encoding

Photochromism has been an efficient approach to improve authenticity of commercial products. In order to prepare an authentication nanofibrous film with mechanical reliability, it has been crucial to improve the engineering production route of the authentication materials. Herein, we electrospun photoluminescent nanofibrous film with a fiber diameter of 50–200 nm from the environmentally-friendly polylactic acid embedded with nanoparticles of rare-earth activated strontium aluminate (NRESA; 10–15 nm). The created nanocomposite film was colorless in daylight, and became an intense green in ultraviolet light. The strontium aluminate photochromic agent must be applied in the nanoparticle form to ensure film transparency by enhancing its dispersion without aggregation in the electrospun polylactic acid nanofiber bulk. An emission peak was observed at 518 nm after excitation of the pigment-polylactic acid nanofibers at 365 nm. Raising NRESA ratio increased the hydrophobic properties of the pigment-polylactic acid nanofibers without changing their visual or mechanical properties. The transparent films showed high photochromic reversibility without exhaustion under numerous exposure cycles of ultraviolet light and darkness. The nanofibrous mats were elastic and flexible. The current technique is an effective strategy for making a variety of anti-counterfeiting substances.     

柠檬酸诱导合成铯钨青铜及其近红外遮蔽性能

以钨酸钠和碳酸铯为原料,在水热条件下利用柠檬酸有机诱导合成出铯钨青铜（CsxWO3）粉体,并将其分散于聚乙烯醇（PVA）溶液中,在玻璃表面制备CsxWO3薄膜。用X射线衍射仪和能谱仪对CsxWO,粉体的结构和形貌进行了表征,借助紫外一可见分光光度计研究了CsxWO3粉体及薄膜的光吸收性能。结果表明：Cs0.32WO3粉体和薄膜为六方结构,与用同样工艺得到的WO3相比,CsxWO3粉体表现出强烈的近红外吸收性能,粉体吸光度高达1．96,其薄膜表现出良好的近红外遮蔽性能,近红外1100rim处的透光率与町见光区的最高透光率相比,下降了13％～18％;经过紫外光照射后,CsxWO3薄膜表现出良好的光致变色性能,且其近红外遮蔽性能进一步提高,特别是在柠檬酸浓度较高的前驱液中合成的CsxWO3,其薄膜近红外遮蔽性能提高的效果更为明显,近红外区1100nm处的透光率与可见光区的最高透光率相比,下降了26％。     

Rheological studies of ultraviolet curing with an oscillating plate rheometer

The dynamic viscoelastic behavior during UV curing was studied for thin liquid films of epoxy acrylate prepolymer by the use of an oscillating plate rheometer. The dynamic viscosity rapidly increases after a certain period of irradiation, so that the UV curing process has the minimum exposure energy required to start polymerization. The minimum exposure energy markedly increases with increasing sample thickness; this results from the inconsistency of degree of curing in the direction perpendicular to the shearing surface. Since free radicals which initiate polymerization are formed by photochemical decomposition of initiator, the ability to cure a film depends on the light intensity at a given depth of the film. the attenuation of light in the film is primarily responsible for this inconsistency. When UV light is applied through a UV filter, the curing behavior is analyzed by a single exponential decay of light with depth because the curing is induced by absorption of a monochromatic light of 365 nm. On the other hand, when UV light from a UV lamp whose output spectrum is a continuum is directly applied, the curing behavior is explained by a combination of energy absorption at different wavelengths. In both cases, the theoretical curves of dynamic viscosity predicted in relation to spectral sensitivity show a good agreement with the experimental results.     

Fabrication and photoresponse of ZnO nanowires/CuO coaxial heterojunction

The fabrication and properties of n-ZnO nanowires/p-CuO coaxial heterojunction (CH) with a photoresist (PR) blocking layer are reported. In our study, c-plane wurtzite ZnO nanowires were grown by aqueous chemical method, and monoclinic CuO (111) was then coated on the ZnO nanowires by electrochemical deposition to form CH. To improve the device performance, a PR layer was inserted between the ZnO buffer layer and the CuO film to serve as a blocking layer to block the leakage current. Structural investigations of the CH indicate that the sample has good crystalline quality. It was found that our refined structure possesses a better rectifying ratio and smaller reverse leakage current. As there is a large on/off ratio between light on and off and the major light response is centered at around 424 nm, the experimental results suggest that the PR-inserted ZnO/CuO CH can be used as a good narrow-band blue light detector.