掺钯纳米WO3薄膜气致变色窗研究

报道了以钨粉和H2O2为原料,采用溶胶凝胶技术和旋转镀膜方法,制备出掺钯气致变色WO3纳米薄膜;使用两块普通玻璃,其中一块内侧涂膜,做成四边封合中空气致变色窗,通以稀薄H2获得最佳致色响应时间小于10 s,在2 min之内700nm波长处的透过率变化超过60%.研究了热处理温度、催化剂钯掺量、薄膜厚度对薄膜特性的影响.     

水对纳米掺钯WO3薄膜气致变色性能的影响

以W粉为原材料,通过溶胶凝胶法结合提拉镀膜法制备了掺钯的气致变色WO3纳米多孔薄膜,并采用不同温度对该薄膜进行了热处理;最后制作成简易的气致变色窗。分别采用傅立叶红外光谱仪(FT-IR)、原子力显微镜(AFM)表征了薄膜中水的存在和薄膜的表面形貌,采用紫外/可见/近红外分光光度计对薄膜致褪色过程的透射率随时间的变化进行原位动态的测试,分析了不同阶段的水的存在对薄膜气致变色性能的影响。研究结果表明:随着气致变色循环次数的增加,薄膜生成水逐渐增加,破坏了薄膜的表面结构,堵塞了薄膜的孔洞,使薄膜气致变色时间延长,但不影响薄膜的致色深度;环境吸附水对薄膜有毒化作用,既延长了薄膜的气致变色的时间也使气致变色深度降低;而适量的薄膜结构水的存在有利于提高薄膜的气致变色速率。     

SiO2纳米复合稳定WO3薄膜气致变色特性研究

以钨粉为主要原料,采用过氧化法及提拉技术制备WO3薄膜,通过SiO2纳米颗粒复合改性提高了WO3薄膜的气致变色稳定性.测试并研究了SiO2复合掺杂对溶胶颗粒分布、气致变色稳定性等的影响,通过测试薄膜循环中红外振动吸收的演变,深入研究了SiO2纳米复合对WO3薄膜气致变色性能影响的内在机制.研究结果表明,SiO2的掺杂抑制了WO3薄膜内的共角聚合,将薄膜的致/褪色循环次数由20次提高到500次以上,WO3-SiO2复合薄膜的稳定网络结构是提高其气致变色循环稳定性的主要原因.     

WO3纳米薄膜的制备与气致变色特性研究

报道了以钨粉为原料，采用溶胶一凝胶技术和旋转镀膜方法，制备出了气致变色WO3纳米薄膜。采用椭偏仪、X射线衍射仪(XRD)、场发射扫描电子显微镜(FE-SEM)、红外光谱仪以及可见光分光光度计等方法分析了薄膜的特性。研究结果表明热处理使得薄膜致密，折射率增大，厚度减小，薄膜结晶；过氧键消失，WO3微结构发生了变化，共角W-O-W键吸收越来越强，且向高波数方向移动。这些变化归因于热处理导致的WO3颗粒形状、团聚状态的变化以及应变键的产生。WO3纳米薄膜具有很好的气致变色特性，致色与退色态透射率变化超过60％，变色起因于H扩散到WO3薄膜中形成的小极化子吸收。     

WO3薄膜气致变色特性的研究进展

WO3薄膜是一种优良的气致变色材料,对其气致变色特性的研究有助于开发出更具应用潜力的可控变色器件.介绍了WO3气致变色的研究进展,综述了热处理和掺杂改性对气致变色的影响,总结了两种被人们普遍认同的WO3气致变色机理,并且对今后的研究方向提出了一些看法.     

Pt／WO3纳米薄膜的氢敏特性

用溶胶-凝胶法和磁控溅射法相结合制备了催化剂Pt掺杂的WO3纳米薄膜,通过改变氢气的体积分数、催化剂Pt的含量及热处理温度等实验因素,对Pt／WO3薄膜的氢致变色性能进行了测试;并利用X射线光电子能谱仪（XPS）分析了薄膜的氢敏机理。实验结果表明：先用溶胶-凝胶法制得WO3薄膜,然后再用磁控溅射法在该WO3薄膜上溅射掺杂5％的Pt,制得Pt／WO3双层纳米薄膜,经100℃热处理后,可以获得性能稳定且具有良好氢敏特性的优质薄膜;薄膜能检测的氢气浓度低至0．008％;XPS分析表明,W^5＋与W^6＋之间的转换是引起WO3薄膜氢致变色现象的主要原因。     

制备WO3电致变色薄膜的低压反应离子镀工艺研究

在电子束蒸发镀膜的基础上,引入低压反应离子镀工艺制备WO3电致变色薄膜,研究不同氧分压对WO3薄膜电致变色特性的影响,实验结果表明制备时选择工作气体氩气分压为2×10-2 Pa,氧分压为4×10-2 Pa时,薄膜具有最好的电致变色特性和最大的变色范围.进而采用低压反应离子镀工艺成功地实现在塑料基板上制备WO3薄膜,并对其电致变色特性进行了研究.同时对比了采用普通电子束蒸发镀膜制备的WO3薄膜的电致变色特性.     

纳米WO3薄膜

综述了纳米WO3薄膜的制备、表征及其在电致变色、气敏材料、共催化剂等方面的应用和作用原理.     

中频磁控溅射制备氧化钨薄膜及电致变色性能研究

采用中频磁控溅射方法,在氧化铟(ITO)玻璃上采用氧化钨(WO3)陶瓷靶沉积薄膜,研究溅射气压对WO3薄膜结构与光学性能的影响规律,并对其电致变色行为进行了探讨.采用X射线衍射(XRD)和扫描电子显微镜(SEM)分析了WO3薄膜的成分结构和表面形貌,紫外可见分光光度计和电化学工作站对薄膜的光调制性能、电致变色伏安特性、...     

纳米晶WO_3电致变色特性(英文)

采用射频反应溅射制备了纳米晶WO3薄膜.基于Berg理论建立了WO3射频反应溅射模型,并分析工艺参数对滞回曲线的影响,基于研究了抽速、基片温度、馈入功率、靶片间距和溅射靶等离子体溅射面积的影响.提出了一种新的消除滞回曲线的制备纳米晶WO3薄膜的方法和优化的工艺参数.论文制备了性能良好的电致变色纳米晶WO3薄膜.分别用环境扫描电镜(ESEM)、X射线光电子能谱(XPS),X射线衍射(XRD)和分光光度计测试了该薄膜,该薄膜在可见光波段,不变色时的透光率大于95%,变色后为65%.纳米晶WO3薄膜的晶粒尺寸在40纳米左右,其高比表面积和缺陷态为电致变色的例子扩散提供了通道.     

Gasochromic switching of Ta and Pd-doped nanocrystalline TiO2 thin films

In this work TiO2:(Ta, Pd) thin films with gasochromic properties have been described. Thin films were prepared by reactive magnetron sputtering process using mosaic Ti-Ta-Pd target. The amounts of dopants were 2.54 at.% and 12.36 at.% of Ta and Pd, respectively. The results of optical measurements performed at presence of ethanol and additional heating of the sample up to 350 degrees C have shown an abrupt change of transmission level from 80% down to 10% in VIS and in IR range. The gasochromic change was very fast. Moreover, rapid cooling (down to room temperature) in an air ambient results in stable thin film coloration. The reverse effect (bleaching) was obtained after annealing at 500 degrees C in an ambient air.     

Ultrafast coloring-bleaching performance of nanoporous WO3-SiO2 gasochromic films doped with Pd catalyst

The gasochromic performance and durability of WO(3)-based films can be improved by doping SiO(2) particles within WO(3) matrix forming nanoporous supporting network and dispersing Pd catalyst inside films with enhanced catalytic activity. Nanoporous WO(3)-SiO(2) composite films loaded with Pd catalyst were prepared by sol-gel dip-coating process and served as an active chromogenic layer to fabricate a double-glazed gasochromic device. The structure, morphology, optical properties and gasochromic performance of WO(3)-SiO(2) films were fully investigated. The WO(3)-SiO(2) films exhibit excellent gasochromic performance with ultrafast coloring rate of 14.8% per second (%/s) (WO(3): 2.84%/s) and bleaching rate of 44.1%/s (WO(3): 7.18%/s). The transmittance changed between 17.8 and 74.6% during coloring-bleaching cycles, and totally reversibility and stability were achieved.     

Simple fabrication of a Pd-P film on a polymer membrane and its catalytic applications

Composites were prepared by a surface activation by aerosol deposition of Pd nanoparticles (Pd nano seeds) on a poly(tetrafluoroethylene) membrane and subsequent Pd-P film formation by electroless deposition. Activation of the membrane processed by an ambient Pd spark discharge and subsequent fixation of the spark produced Pd nano seeds. Characterizations for electroless Pd-P films indicated that P entered into the crystal lattice of Pd and formed an alloy. The fabricated composites were applied to catalytic applications of formic acid oxidation (FAO) and toluene conversion (TC). The composite catalysts from the simple activation had more stable performances of FAO and TC than those from the conventional Sn-Pd activation, and their better performances might have originated from better purity due to the simple activation that only introduced pure Pd nano seeds.     

光可控气致变色节能窗的应用研究

报道了以钨粉、双氧水和TEOS为原料,采用溶胶-凝胶结合浸渍提拉镀膜技术,制备了SiO2复合WO3气致变色薄膜。通过扫描间,透射电子显微镜,紫外可见分光光度计表征了SiO2复合对WO3结构、形貌及稳定性能的影响。并对实际大小的窗体(1.2m×0.8 m)进行了变色性能测试,结果表明样品具有较快的响应灵敏度,能在数分钟内完成透明和深蓝色转换。在三年的不间断测试中并没有明显的性能衰减,仍有较理想的变色效果。     

SERS Active Surface in Two Steps,Patterning and Metallization

Robust and reproducible metallized nano/microstructured surfaces of polymeric surfaces have been successfully prepared by direct laser interference patterning (DLIP) of commercial polymeric films followed by sputtering of metallic thin films. The SERS spectra for 2‐thioaniline adsorbed on a structured polycarbonate surfaces covered with a gold or platinum film showed a ca. three order of magnitude enhancement over a flat surface with the same metal film. The method here reported is suitable for mass production of substrates for SERS since large areas (several cm²) can be structured in ca. 1–5 s.     

纳米食品保鲜膜研究进展

目的 综述纳米材料及其制备纳米保鲜膜,以及其在食品保鲜中研究和应用现状。方法 介绍常用纳米包装保鲜膜中常用的纳米材料,包括ZnO纳米粒子、TiO₂纳米粒子、SiO₂纳米粒子、介孔SiO₂纳米粒子、Ag纳米粒子,以及纳米保鲜膜制备方法。结果 在传统膜或保鲜膜中添加纳米粒子,可以有效改善膜的力学性能、阻隔性能及抑菌性能,可有效延长食品货架期和贮藏保鲜期。结论 与传统膜相比,纳米膜在食品包装保鲜具有优异特性,具有巨大应用潜力。然而,如何改善光催化等纳米薄膜应用的局限性需要进一步研究。     

纳米TiO2薄膜光催化剂的制备及性能研究

以钛酸四丁酯作为前驱体,用溶胶一凝胶法,在玻璃载体上煅烧制备了纳米TiO2薄膜光催化剂,利用扫描电子显微镜（SEM）、X射线衍射（XRD）等表征技术研究了TiO2薄膜的形貌和特性,其光催化性能用4支20W紫外石英杀菌灯照射TiO2薄膜分解亚甲基兰染料溶液表征,结果表明,该催化剂具有锐钛班红石混合晶相和纳米花状结构,纳米TiO2薄膜的光催化能力随着镀膜层数的增加而增加。     

Characterization of Ni–Pd alloy as anode for methanol oxidative fuel cell

Electrochemical deposition of Ni–Pd alloy films of various compositions from bath solution containing ethylenediamine (EDA) was carried out to use as anode material for methanol oxidative fuel cell in H₂SO₄ medium. Electronic absorption spectrum of bath solution containing Ni²⁺, Pd²⁺ ions and EDA indicated the formation of a four coordinate square planar metal–ligand complex of both the metal ions. X-ray diffraction (XRD) patterns of the deposited alloy films show an increase in Pd–Ni alloy lattice parameter with increase in Pd content, and indicate the substitution of Pd in the lattice. A nano/ultrafine kind of crystal growth was observed in the alloy film deposited at low current density (2.5 mA cm⁻²). X-ray photoelectron spectroscopic (XPS) studies on the successively sputtered films showed the presence of Ni and Pd in pure metallic states and the surface concentration ratio of Ni to Pd is less than bulk indicating the segregation of Pd on the surface. Electro-catalytic oxidation of methanol in H₂SO₄ medium is found to be promoted on Ni–Pd electrodeposits. The anodic peak current characteristics to oxidation reaction on Ni–Pd was found typically high when compared to pure nickel and the relative increase in surface area by alloying the Ni by Pd was found to be as much as 300 times.     

SiO2/CaCO3纳米复合粒子填充改性聚丙烯

通过简单的工艺条件和步骤制备S iO2包覆C aCO3的核壳结构纳米复合粒子,采用硅烷偶联剂对其和纳米S iO2实心粒子进行表面改性处理,并用处理后的两种粒子分别对聚丙烯进行填充改性,然后比较其对复合材料力学性能的影响。结果表明,利用纳米S iO2/C aCO3复合粒子填充改性聚丙烯,可同时达到增强、增韧的目的,而且对材料力学性能的改性效果与纳米S iO2实心粒子的改性效果相近。