显色工艺对纳米CdSexS1-x微晶玻璃光吸收曲线性能的影响

采用不同的热处理显色工艺对掺杂Se和CdS着色剂的硼硅酸盐玻璃进行热处理,制备出一系列的纳米硒硫化镉颜色玻璃,研究了热处理显色工艺对玻璃光透过性能的影响。结果表明,玻璃的截止吸收波长位置取决于热处理条件;采用低温长时间热处理工艺,使所制备的玻璃具有较高的光透过率和完整的吸收边界。微观结构分析表明,热处理后玻璃中出现的纳米微晶等结构变化是导致玻璃着色、出现光截止吸收的根本原因。     

基于ZnO对Yb~(3+)能量传递的宽带光谱转换微晶玻璃

通过熔融冷却方法制备出无掺杂和Yb~(3+)掺杂的40SiO_2·10Al_2O_3·40ZnO·10K_2CO_3·xYb_2O_3(x=0,0.3)玻璃,之后分别在680、730、780℃下对其进行热处理得到含ZnO纳米晶的微晶玻璃。通过X射线衍射、透射电子显微镜验证了不同温度热处理后ZnO纳米晶在玻璃基质中的析出以及Yb~(3+)掺杂对析晶尺寸和析晶度的影响;通过稳态和时间分辨光谱研究了Yb~(3+)掺杂玻璃及微晶玻璃的发光性能。结果表明:微晶玻璃中.ZnO纳米晶尺寸和析晶度均随热处理温度的升高以及Yb~(3+)掺杂浓度的增加而增大。紫外光激发下Yb~(3+)掺杂玻璃的红外发射是基于Yb~(3+)电荷迁移态(CTS)吸收;395 nm激发下Yb~(3+)掺杂微晶玻璃的红外发射是源于ZnO纳米晶对Yb~(3+)离子的能量传递。ZnO纳米晶的可见发光强度随着热处理温度的提高而随之减弱:而源于Yb~(3+)的~2F_(5/2)→~2F_(7/2)跃迁的红外发射的强度在730℃热处理的微晶玻璃中最强。     

Sm3+掺杂碱锌硼硅酸盐玻璃析晶过程的微观结构研究

采用HTEM,NMR以及红外光谱技术,研究适宜半导体微晶掺杂的Sm3 掺杂碱硼硅酸盐基础玻璃在热处理过程中,玻璃结构的变化特点.研究结果表明,含Sm3 基础玻璃失透的主要原因在于在热作用下玻璃中[SiO4]4-以及[BO4]4-四面体结构首先分解形成了富硅相以及富硼相,稀土Sm3 则富集到富硼相中,并进一步析出了硼酸钐晶体;通过优化玻璃的组成能够改进基础玻璃的热稳定性.     

纳米功能颗粒掺杂玻璃的制备及光学特性

纳米功能颗粒掺杂玻璃具有优异的光学性能，是当前国际光学功能材料研究的热点之一。对纳米功能颗粒(金属和半导体)掺杂玻璃的制备工艺及特点作简单介绍，着重阐述该类复合玻璃的光学特性和应用。结合实验和对文献资料的分析，指出了今后的研究方向和应用前景。     

微晶玻璃的玻璃相

微晶玻璃几乎都含有未结晶玻璃的残余,残余玻璃相的组成和体积分数取决于母体玻璃的组成与热处理制度。 残余玻璃相可能显著地影响到微晶玻璃的一些重要性质。例如,某些与离子穿过微晶玻璃结构的扩散性有关的及与微晶玻璃的粘滞流动有关的性质,都强烈地依赖于玻璃相的化学组成和体积分数。此外,微晶玻璃的机械强度、微裂纹增大方式、化学稳定性以及对可见光的透过度等也受到玻璃相的影响。     

Yb~(3+)/Er~(3+)共掺锗酸盐氧氟微晶玻璃的白光输出

对组成为50GeO_2-20Al_2O_3-15CaF_2-15LiF稀土离子锗酸盐氧氟玻璃在550℃微晶化热处理24h,得到了透明的微晶玻璃。X射线衍射表明:玻璃中析出了CaF_2纳米晶粒,晶粒尺寸在17 nm左右。在980 nm泵浦光的激发下,Yb~(3+)/Er~(3+)双掺微晶玻璃产生了蓝绿红上转换荧光。随着玻璃中Yb~(3+)的掺杂浓度的增加蓝光和红光荧光强度增大,其中5%Yb~(3+)/1%Er~(3+)(摩尔分数,下同)的微晶玻璃样品的上转换发光已经出现白光效果。通过研究一系列高Yb~(3+)/Er~(3+)浓度比的共掺微晶玻璃样品,实现了对上转换红光绿光与蓝光的荧光强度比例的调整,当Yb~(3+)掺杂浓度为12%、Er~(3+)掺杂浓度为0.01%时,微晶玻璃的上转化发光接近白光。     

用原位透射电镜技术观察微晶玻璃结晶过程的研究进展（英文）

总结了利用原位透射电子显微镜(TEM)技术观察纳米颗粒在玻璃介质中结晶过程的研究进展。原位TEM技术可以提供一个实时记录纳米颗粒形核结晶以及长大的动力学平台,该技术为理解和优化微晶玻璃中纳米颗粒生长机理提供了方法,从而为实现优化纳米颗粒结晶性、形貌以及其物理特性提供了直接途径。此外,还总结了微晶玻璃中纳米颗粒的成核机理,详细讨论了温度和电子束(E-beam)对纳米颗粒在玻璃介质中生长动力学过程的影响,并提出了原位TEM技术在微晶玻璃材料中应用的机遇和挑战。     

Tb~(3+)掺杂氟硅酸盐微晶玻璃的制备及性能研究

结合当前对光学材料发展的需求,制备了Tb3+掺杂的氟硅酸盐微晶玻璃,并研究了其晶化工艺和发光性能。通过DSC分析,确定了母体玻璃的析晶温度652℃。通过研究样品不同保温时间下的晶化热处理工艺制备出含CaF2纳米晶的透明微晶玻璃,且保温时间为24 h时获得最佳晶粒尺寸。探讨了365 nm激发下Tb3+掺杂氟硅酸盐微晶玻璃的光谱性能,发现在Tb3+掺杂微晶玻璃样品能发出强烈的绿色荧光(545 nm)。随着热处理时间增加,其荧光发射强度呈现增高的趋势,在热处理24 h时发射光谱强度最强。     

无铅金红玻璃的研究

以钠钙硅酸盐代替铅硅酸盐为基础成分,掺杂金制备了金红玻璃。用分光光度计测量了的透过率曲线。用扫描电镜观察了玻璃表面形貌及金颗粒尺小。结果表明:玻璃的吸收峯为540nm,金颗粒尺寸为40~80 nm,玻璃呈玫瑰红色。这种无铅玻璃减少铅的污桨,降低了成本。     

三阶非线性光学玻璃材料的研究进展

评述了三阶非线性光学玻璃材料的种类、制备方法、基本特性及评价体系、非线性现象的起源、基本原理,几种典型非线性光学材料的潜在应用。简要介绍了该领域国内外的最新研究成果,重点阐述了掺杂CdS,PbS,Au等量子点尺寸、量子点玻璃微结构与光学和非线性光学性质的关系。评述了掺CdS、PbS这两种典型半导体量子点玻璃材料在光波导和激光饱和吸收器等领域的研究进展。指出在掺杂易极化金属,如;Pb,Bi,Nb等纳米团簇,掺杂半导体元素,如:Ge,Si等纳米团簇,掺杂Ⅴ-Ⅵ族半导体化合物,如:In_2Se_3,Bi_2S_3等纳米团簇量子点玻璃中,会有大的量子尺寸效应和非线性光学效应。     

纳米WO_3·NiO·0.33H_2O光催化剂的结构与性能

采用复合表面活性剂作分散剂,用微波辐射法制备了较大比表面积的纳米复合半导体材料WO3·NiO·0.33H2O,利用XRD、TEM、BET和UV-Vis漫反射光谱技术对固体材料的组成结构和光吸收性能进行了表征。结果表明,微波辐射法制备的材料晶粒小,孔隙率大,结晶度高,比表面积大,为66.37m2/g;材料WO3·NiO·0.33H2O光响应波长达600nm,增强了光能利用率及光催化活性。     

硫掺杂纳米Li2FeSiO4/C制备与电化学性能

采用固相反应法制备了 Li2FeSiO4-xSx/C (x=0,0.01,0.02,0.03)纳米正极材料。通过 X 射线 衍射（XRD）、扫描电子显微镜（SEM）、能量色散光谱仪（EDS）、X 射线光电子能谱（XPS）、拉 曼光谱（Raman）、红外吸收光谱（FTIR）及恒流充放电测试研究了材料的微观形貌、晶体结构和 电化学性能。结果表明，Li2FeSiO3.98S0.02/C 形貌呈纳米球状，平均粒径为45.38nm，纳米尺寸的粒径有利于缩短Li+的扩散途径；碳包覆抑制纳米晶粒的生长，可以增强材料的导电性；硫掺杂能扩大材料的隧道间距，加快了Li+的迁移速率。Li2FeSiO3.98S0.02/C 表现出较高的充放电比容量、优异的倍率性能以及循环稳定性，在 0.1C 下首次放电比容量高达 180.1mAhg -1，在 10C 下放电比容量为 85mAhg-1,1C 下循环 100 次后的容量保持率为 91.3%。     

Specific features of the growth of CdSe nanocrystals in fluorophosphate glasses

The choice of the composition of the fluorophosphate vitreous matrix used for optimizing the growth of CdSe nanocrystals with a narrow size distribution is justified. Investigation of the X-ray diffraction parameters has revealed that nanocrystals with sizes varying over a wide range have a hexagonal structure. The evolution of the absorption spectra of fluorophosphate glasses containing CdSe semiconductor nanocrystals is studied. It is shown that the growth mechanism of CdSe nanocrystals differs radically from the nucleation mechanism. The time dependences of the nanocrystal size exhibit an intricate three-stage behavior. The first stage is accompanied by a shift in the absorption spectrum toward the long-wavelength range. After the first stage, the time dependences are characterized by “fast” and “slow” portions. In the fast portion, the exponent of the time dependence of the nanocrystal size increases from 0.4 to 1.0 with an increase in the annealing temperature. The assumption is made that the spinodal decomposition of phases under hyperbolic diffusion occurs in the system under investigation.     

Size-Quantized Nanocrystalline Semiconductor Films

This paper is a review of our work on nanocrystalline semiconductor films which exhibit pronounced size quantization effects in three dimensions, manifested by large blue-shifts in their optical absorption spectra. The films are prepared by either chemical solution deposition (CdSe and PbSe) or by electrodeposition from nonaqueous electrolytes (CdSe and CdS). Except for PbSe, where the nanocrystals are surrounded by a matrix, the films are comprised of aggregated nanocrystals. Crystal size (typically from <4 nm to >6 nm), and therefore absorption spectra, can be controlled by deposition temperature, illumination during deposition (for chemically deposited films), solution composition, and post annealing. The crystal size dependence of chemically-deposited films on experimental parameters (temperature, illumination, reactant concentrations) is discussed. CdSe nanocrystals were epitaxially electrodeposited on single-crystal Au. The nanocrystal distribution (isolated or aggregated) could be controlled by deposition current and temperature. All these films exhibit photoelectrochemical behavior but no corresponding solid state photovoltaic behavior. A model is proposed based on electron/hole separation by kinetic differences in charge injection into an electrolyte rather than by a built-in space charge layer in the semiconductor. The films can behave as both ‘n’ - or ‘p’-type, with respect to direction of photocurrent flow, by changes in the semiconductor surface properties and/or the electrolyte, in agreement with this model.     

水热法制备CdSe和PbSe共负载TiO2纳米带复合材料

采用两步水热合成过程制得了CdSe或/和PbSe负载的TiO2纳米带复合材料。用XRD、SEM、TEM、UV-Vis吸收和FTIR等测试技术对产物进行了一系列表征。结果表明,六方相CdSe粒子或/和立方相PbSe粒子直接负载在四方相锐钛矿型TiO2纳米带表面,其中呈近球形CdSe粒子的粒径主要在100~400 nm,而呈近立方体形PbSe粒子的边长主要在300~1 000 nm。CdSe和PbSe共负载TiO2纳米带复合材料在可见光区域有强的光吸收。由FTIR谱图推断,在复合材料载体TiO2纳米带结构中掺杂有少量Cd2+或/和Pb2+离子。     

酸处理后坡缕石的孔结构变化

在90℃,坡缕石分别用不同浓度的盐酸处理1.5h,对制得样品的物相、比表面积和微孔结构以及微观形貌进行了研究.结果表明:酸处理可以提高坡缕石的比表面积,改变坡缕石晶体的孔结构,随着酸浓度的改变,坡缕石的总比表面积、微孔比表面积和外比表面积都随之发生改变.当酸浓度小于等于3 mol/L时,坡缕石颗粒聚集体逐步被解离,溶蚀作用主要发生在孔道内,晶体结构能保持相对完整;当酸浓度大于3 mol/L时,部分颗粒被溶蚀掉.结果说明H 能进入到坡缕石的晶体孔道中产生作用,使晶体的孔道不断扩大,孔径最大可以达到0.62～0.75nm,但孔径超过0.62～0.75nm后晶粒会被破坏.     

管状微纳米Ag2S晶体的水热法制备方法研究

在低温水热条件下,以不同硫源和银片为反应物,制备出了微纳米级Ag2S晶体,其中以硫粉为硫源、乙醇为溶剂时制备出了少见的拥有中空管状形貌的Ag2S微纳米材料,并用X射线粉末衍射仪（XRD）、扫描电子显微镜（SEM）分别对产物Ag2S晶体的结构和形貌进行了表征和分析。     

微纳米气泡及其在环境工程领域的应用

微纳米气泡因其区别于传统气泡的突出特性,近年来被广泛应用到环境工程领域,并表现出显著的技术优势与广阔的应用前景.文章简要介绍了微米气泡和纳米气泡的特性、制备方法、表征手段及其在环境工程领域的应用现状,并针对性地指出了当前各方面存在的问题,给出了解决对策和方向.最后,对微纳米气泡及其在环境工程领域应用的发展方向和应用前景...     

Effect of Silicone Nano,Nano/Micro and Nano/Macro‐Emulsion Softeners on Color Yield and Physical Characteristics of Dyed Cotton Fabric

The study of silicone nano‐emulsions and softeners to alter physical properties of undyed cotton fabric has recently gained a substantial interest. However, systematic investigation of silicon nano‐emulsion softeners on dyed cotton fabric has not so far been conducted. This paper deals with the application of silicone nano‐, micro‐, and macro‐emulsion softeners, and combinations of nano/micro and nano/macro, on dyed cotton fabric. We report the effect of silicon nano/micro‐ and nano/macro‐emulsion softeners on color yield and physical characteristics of dyed cotton fabric. All bleached fabrics were dyed with CI Reactive Black 5 and then treated with known concentrations of silicone softeners by the pad‐dry method. The silicone nano‐emulsion was combined with micro‐ and macro‐emulsion softeners using blending ratios of nano/micro (1:1) and nano/macro (1:1). Treated fabrics were compared in terms of physical properties such as fabric handling, wrinkle recovery angle, bending length, abrasion resistance and tensile strength. The color changes were evaluated by color yield (K/S) values and total color difference (ΔE_cmc). The results revealed that the silicon nano‐emulsion had better physical properties than micro‐, macro‐ and combination nano/micro‐ and nano/macro‐emulsion softeners. Among all treated samples, nano‐emulsion softeners showed better ΔE_cmc values. Scanning electron microscopy analysis suggests that the fiber morphology of treated fabrics was very smooth and uniform.     

Role of Cu/S ratio and Mg doping on modification of structural and optical characteristics of nano CuS

Nano CuS with different Cu to S ratio and also Mg-doped nano CuS are prepared using a thermolysis procedure under nitrogen flows. The effect of changing copper to sulfur ratio in preparation of CuS under flowing nitrogen and also Mg-doped CuS on the lattice parameters and crystallite size is studied using X-ray diffraction data by applying the Rietveld profile method. Scanning electron microscope mapping is used to verify the distribution of different elements over undoped and doped CuS samples. Fourier transforms infrared spectroscopy spectra confirm that the structure of CuS is not altered by doping or changing of the Cu to S ratio. In order to examine the effect of changes of Cu to S or Mg doping on the absorption behavior of nano CuS, ultraviolet spectroscopy is used. The energy gaps of different samples are determined using Tauc’s relation. The photoluminescence spectroscopy reveals that all samples exhibit violet and blue sub-emissions except a CuS with Cu:S ratio 1:4 which also emits green sub-emission.