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1.
利用射频磁控溅射法,室温下通过交替溅射ZnO和Ag,在PET纤维基材上制备ZnO/Ag/ZnO纳米结构多层膜。运用扫描电镜和原子力显微镜对薄膜表面形貌进行分析,用分光光度计测试其透光性能,用四探针电阻测试仪测试其方块电阻。结果表明:纤维基Zno/Ag/ZnO多层膜致密、均匀,对紫外光表现为较强的吸收能力;Ag膜厚度的改变可以调控多层膜的光电性能;ZnO(40nm)/Ag(20nm)/ZnO(40m)多层膜呈现多晶结构,方块电阻为4.4Ω;透光率接近30%。  相似文献   

2.
在低温下制备了粒径小于10nm的ZnO纳米晶,用旋涂法制备ZnO纳米晶薄膜,XRD分析ZnO晶相是纤锌矿结构;SEM与AFM表明,纳米晶薄膜在300%退火后薄膜的厚度明显减小到130nm,表面粗糙度降低到3.27nm,粒径明显增大;紫外-可见吸收和透射比光谱表明,随着退火温度的增加,吸收边发生了红移,吸收肩更明显,薄膜具有高的透射率(75—85%);薄膜方阻随温度增加而增大,300℃以下退火方阻增加很小(小于8.5Ω/sq),400℃以上退火方阻大幅增加(大于21.1Ω/sq),因此,ZnO纳米晶薄膜最优退火温度点为300℃。  相似文献   

3.
采用高温熔融-退火法在钠硼铝硅酸盐(SiO2-B2O3-Na2O-Al2O3-ZnO-AIF3-Na2O)玻璃中生长了PbSe量子点,通过X射线衍射(XRD)、透射电镜(TEM)、光致荧光(PL)谱等研究了玻璃配料中不同ZnO含量对PbSe量子点尺寸和浓度的影响,结果表明,ZnO含量占总玻璃配料质量比约9.4%时,生成的量子点尺寸比较均匀,直径约为6.5nm,且浓度较高,PL谱强度最强,辐射峰位于1790nm,FWHM为296nm。玻璃配料中加入适量的ZnO有助于PbSe量子点的形成,减少Se元素的挥发,使玻璃中的量子点尺寸分布趋于均-化。  相似文献   

4.
首先在低温下制备了粒径小于10nm的ZnO纳米晶,然后采用旋口法制备了ZnO纳米晶薄膜,XRD分析ZnO晶相是纤锌矿结构;SEN与AFM表明,纳米晶薄膜在300℃退火后薄膜的厚度明显地减小到130nm(未退火200nm),粒径明显增大,表面粗糙度减少到3.27nm(未退火4.89nm);紫外-可见吸收和透射比光谱表明,随着退火温度的增加,吸收边发生了红移,吸收肩更明显,薄膜具有高的透射率(75—85%),随着温度增加薄膜方阻增大,300℃以下退火方阻增加很小(小于8.5Ω/sq),400℃以上退火方阻大幅增加(大于21.1n/sq),假定存在最优退火温度点(300℃)。  相似文献   

5.
纳米银粒子在微乳液中的制备及其抗菌性能   总被引:1,自引:0,他引:1       下载免费PDF全文
在以二丁酸二异辛酯磺酸钠为表面活性剂、异辛烷为油相形成的W/O型微乳体系中,以AgNO3为银源、抗坏血酸为还原剂,讨论了AgNO3浓度、抗坏血酸浓度以及水核半径(W)对制备纳米银粒子的影响。利用紫外一可见光谱分析(UV-Vis)、透射电镜(TEM)和纳米粒度仪对制得的纳米银进行表征。结果表明,在AgNO3浓度为0.2mol/L,抗坏血酸浓度为0.2mol/L,W值为10的条件下,得到大小为10nm左右,单分散性好的均匀球状纳米银溶胶。抗菌性能测试表明,当纳米银粒子质量浓度为10μg/mL时,对大肠杆菌的杀菌率达98%以上。  相似文献   

6.
将超声波辐照技术引入到聚合物纳米材料的制备过程中,制备了丙烯酸丁酯(BA)/丙烯酰胺(AM)/纳米SiO2复合材料。粒径及粒径分布测试表明制备的乳胶粒粒径在400nm~500nm之间;反应过程中粒径经历了从小到大,然后又变小的过程;当超声输出功率为450W时,平均粒径最小,粒径分布也最窄;随着体系中丙烯酰胺(AM)含量的提高,粒径变小,粒径分布也变窄。  相似文献   

7.
采用水热法制备了Bi2W06催化剂,并以Fe2O3对Bi2WO6进行改性,合成了新型复合光催化剂№03/Bi2w06。采用XRD、DRS等对合成的催化剂进行了表征。以氙气灯为光源(λ〉420nm),以罗丹明B为目标降解物进行了光降解试验。结果表明,与Bi2W06相比,Fe2O3/Bi2W08的光催化性能有所提高,其中,...  相似文献   

8.
利用乙醇辅助水热法制备出ZnO/TiO2和ZnO/SnO2两种纳米复合粒子,采用X射线衍射(XRD)、扫描电子显微镜(SEM)及x射线能谱(EDS)分析方法对其结构进行表征,并通过紫外-可见漫反射光谱(uvvis)分析探讨了其紫外可见吸收性能,研究结果表明,在紫外-可见漫反射吸收光谱图中,ZnO/TiO2和ZnO/SnO2纳米复合粒子的最大吸收峰较纯纳米ZnO蓝移。同时,在可见光波段也有较弱吸收,拓展了其紫外吸收光谱。  相似文献   

9.
机械化学法合成纳米ZnO粉体   总被引:5,自引:0,他引:5  
利用机械化学法合成了单相ZnO粉体,XRD分析结果表明,ZnSO4/NaOH(mol比)在1/2.1-1/3.0之间均可合成ZnO粒子,ZnO产率在ZnS04/Na0H为l/2.5时最大.TEM分析表明,ZnO粒子的粒径在40-80nm范围.对于反应机理,认为是固—固反应中放出的大量的热,使Zn(OH)2直接转化为ZnO粒子.光吸收性能表明,纳米ZnO粉体的紫外吸收性能(200-400nm)较普通ZnO粉体强得多.  相似文献   

10.
HPLC法测定血竭药材中血竭素的含量   总被引:1,自引:0,他引:1  
本文建立了血竭药材中血竭素的测定方法,采用Agilent TC—C18柱,以乙腈-0.05mol/LKH2PO4(0.1%H3PO4水溶液)=40:60;流速:1.0mlMmin;检测浓度:440nm和270nm,回收率为96.25%~100%之间,RSD为1.67%。实验结果表明该方法简便、快速、精密度高。  相似文献   

11.
均匀沉淀法制备碳纳米管/氧化锌复合材料的研究   总被引:2,自引:1,他引:1  
采用均匀沉淀法制备了碳纳米管(CNTs)负栽氧化锌(ZnO)粒子复合材料,并利用扫描电子显微镜(SEM)、X光衍射分析(XRD)以及热失重分析(TGA)手段对复合粒子进行了表征.研究结果表明:锌离子浓度取0.4mol/L至1.0mol/L时,所得复合材料中的氧化锌粒子大小均匀细小,分散性较好,形貌以粒状为主,大小在40nm左右;纳米氧化锌粒子与碳纳米管结合力较强,CNTs/ZnO复合材料在超声作用下能够稳定存在;反应时间越长,氧化锌粒子含量越高,晶粒越大;热解温度越高,热解时间越长,氧化锌晶粒尺寸越大.  相似文献   

12.
ZnO thin films have been deposited by pulsed laser deposition (PLD) and ultrasonic spray pyrolysis (USP) method, respectively. X-ray diffraction and transmission electron microscopy characterizations indicate that ZnO film grown by PLD exhibits better crystallinity than that grown by USP. Photoluminescence spectra show that the near-band edge ultraviolet emission of film grown by PLD is narrower and shifts to higher energy, compared with that of film grown by USP. In the visible range, ZnO film grown by PLD exhibits four local level emission centered at 470 nm, 486 nm, 544 nm, and 613 nm, respectively, while the film grown by USP only presents a weak broad band emission centered at 502 nm. Hall measurement shows higher carrier density and lower hall mobility in ZnO film grown by PLD than that in film grown by USP. The higher density of intrinsic defects as well as higher crystallintiy is considered to account for the difference of photoluminescence in ZnO film grown by PLD with that in film grown by USP.  相似文献   

13.
The photoluminescence (PL) characteristics of ZnO/SiO2 composite particles were investigated. ZnO/SiO2 composite particles were synthesized utilizing the consecutive sol–gel spray drying method by incorporating sodium lauryl sulfate (SLS) as a particle morphology control agent. The effect of SLS concentration and ZnO ratio on precursors was studied further on the composite particle morphology and PL performance. Elevating the SLS concentration exhibited a reduction in the particle diameter and an increase in particle uniformity. The particle diameter without SLS was 6.18 µm and reduced to 2.6 µm with the addition of SLS at 3 critical micelle concentrations (CMC). The decrease in ZnO concentration also reduced the particle diameter of the ZnO/SiO2 composite to 1.74 µm at a ZnO concentration of 25% mol. In addition, the increase in the excitation wavelength from 230 nm to 320 nm indicates a shift in the peak emission intensity at higher wavelengths from 467 nm to 645 nm. The excitation wavelength-dependent photoluminescence phenomenon was exhibited by incorporating silica into the ZnO precursor pre- and post-drying to deliver composite particles. The addition of silica to the composite particles can augment the PL emission intensity without causing a shift in the PL emission peaks when excited at the same wavelength. The 25% mol ZnO composite particles with the addition of SLS 3 CMC had the highest PL emission intensity. The amount of silica nanoparticles sufficient to trap the ZnO nanoparticles in the droplet is an important factor besides the size and uniformity of the particles, which causes the high intensity of PL emission.  相似文献   

14.
Optical characterization of ZnO thin films deposited by Sol-gel method   总被引:1,自引:0,他引:1  
In this paper, ZnO thin film is deposited on Pt/TiO2/SiO2/Si substrate using the sol-gel method and the effect of annealing temperature on the structural morphology and optical properties of ZnO thin films is investigated. The ZnO thin films are crystallized by the heat treatment at over 400°C. The ZnO thin film annealed at 600°C exhibits the greatest c-axis orientation and the Full-Width-Half-Maximum (FWHM) of X-ray peak is 0.4360°. A dense ZnO thin film is deposited by the growth of uniform grains with the increase of annealing temperature but when the annealing temperature increases to 700°C, the surface morphology of ZnO thin film becomes worse by the aggregation of ZnO particles. In the results of surface morphology of ZnO thin film using atomic force microscope (AFM), the surface roughness of ZnO thin film annealed at 600°C is smallest, that is, approximately 1.048 nm. For the PL characteristics of ZnO thin film, it is observed that ZnO thin film annealed at 600°C exhibits the greatest UV (ultraviolet) exciton emission at approximately 378 nm, and the smallest visible emission at approximately 510 nm among ZnO thin films annealed at various temperatures. It is deduced that ZnO thin film annealed at 600°C is formed most stoichiometrically, since the visible emission at approximately 510 nm comes from either oxygen vacancies or impurities.  相似文献   

15.
《Materials Research Bulletin》2006,41(11):2123-2129
The zinc oxide thin films on aluminum foil have been successfully prepared by sol–gel method with methyl glycol as solvent. The film was characterized by means of XRD, TG, UV–vis, SEM and AFM, which show that the ZnO/Al film is formed by a layer of ZnO nano-sized particles with average diameter of 52.2 nm. Under the initial concentration of 20 mg/L phenol solution (500 mL) and visible light irradiation time of 3 h, more than 40% of the initial phenol was totally mineralized using two pieces of ZnO/Al thin film as photocatalyst with an efficient irradiation area of 400 cm2. It is a promising visible light responded photocatalyst for the activation of O2 at room temperature to degrade organic pollutants.  相似文献   

16.
In this paper, we report a new and simple method to prepare different concentrations in molarities Eu-doped ZnO films on the ITO glass substrates by ultrasonic spray pyrolysis. The morphologies, crystal structures and optical properties were investigated by using scanning electro microscopy (SEM), X-ray diffraction (XRD) and photoluminescence (PL). The SEM images show that the morphologies of Eu doping concentrations 3 and 9 at.% of ZnO films are lamellae. When the Eu doping concentration in molarities is 6 at.%, the morphology of films are graininess and dense, particle diameter is about 200–250 nm. The XRD results indicate that when the Eu doping concentration is 6 at.%, the structure of Eu-doped ZnO films have better hexagonal polycrystalline structure, and characteristic diffraction peak of Eu2O3 was appeared at 2θ = 50.47°. The PL spectra of different concentrations Eu-doped ZnO films show that for the Eu doping concentration 6 at.%, ZnO film has a stronger red emission at 613 nm with excitation wavelength at 280 nm.  相似文献   

17.
Ordered ZnO porous thin films were fabricated by cooperative assembly method using polystyrene sphere (PS) and ultrafine ZnO particles, in which ultrafine ZnO particles were directly assembled in the voids of PS while the template was being assembled by capillary forces. The influence of experimental parameters, such as evaporation temperature, ZnO concentration and the concentration ratio of PS/ZnO on morphology of the porous structure was mainly studied. The results showed that an ordered porous structure could be obtained by this method. X-ray diffraction (XRD) spectra indicated the porous ZnO thin film was wurtzite structure. The transmissivity decreased with the decrease of wavelength, but still kept above 80% beyond the wavelength of 550 nm. Optical band gap of the ZnO thin film was 3.13 eV.  相似文献   

18.
Hai-li Yu 《Materials Letters》2008,62(27):4263-4265
Decorated nano ZnO/PS organic sol was successively produced by pulsed laser ablation at the interface of ZnO ZnO target submerged in the flowing liquid of butyl acetate solution of PS which contained salicylic acid, then decorated nano ZnO/PS hybrid thin film was obtained. It is found that decorated nano ZnO/PS hybrid thin film radiates intense blue light under ultraviolet radiation and has a broad emission band centered at 448 nm in the emission fluorescence spectrum. TEM shows that the size of the nano ZnO particles distributes between 10 nm and 15 nm. TG-DSC reveals that the heat resistance of decorated nano ZnO/PS hybrid thin film increases.  相似文献   

19.
Kun Han 《Materials Letters》2007,61(2):363-368
Three kinds of different ZnO colloid particles (flowerlike particles, nanoribbons and microspheres) and one kind of ZnO film have been coated with silica via a simple sol-gel method in the Stöber system and ZnO/silica core-shell microparticles or films have been obtained. The thickness of silica shell can be controlled by adjusting the concentration of TEOS added into the system. If the ZnO core is etched off by HCl, corresponding, hollow silica particles or film will be generated.  相似文献   

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