超声喷雾热解法制备SnS薄膜的物性研究

用超声喷雾热解法制备SnS多晶薄膜,对比了三种不同前驱液配比浓度对SnS薄膜性能的影响。XRD测试表明,当前驱液为硫脲(0.5 mol·L-1)+四氯化锡(0.5 mol·L-1)+去离子水时,SnO2的衍射峰强度比较大;当前驱液为硫脲(0.6 mol·L-1)+四氯化锡(0.5 mol·L-1)+去离子水时,SnS的衍射峰占主要地位,其中也含有一定量的SnO2;当前驱液为硫脲(0.7 mol·L-1)+四氯化锡(0.5 mol·L-1)+去离子水时,退火后的薄膜为单一的SnS薄膜,具有斜方晶系结构。SEM观测发现,薄膜均匀、致密,前驱液中硫脲浓度较大时,颗粒也较大。透过谱测试表明,浓度对薄膜透过率影响较小。结合器件的暗I-V和C-V测试,用三种前驱液配比浓度所制备的器件的结特性差异不大;当前驱液中硫脲浓度较大时,载流子浓度相对较大。     

Cu掺杂SnO_2/TiO_2复合薄膜的制备及性能研究

制备Cu掺杂的纳米Sn O2/Ti O2溶胶,采用旋涂法在载玻片上镀膜,经干燥、煅烧制得Cu掺杂的Sn O2/Ti O2薄膜,通过对比实验探讨掺杂比例、条件、复合形式等对结构和性能的影响。采用XRD、SEM、EDS、UVVis等测试手段对样品进行表征,并以甲基橙为探针考察了其光催化降解性能。XRD测试结果显示薄膜的晶型为锐钛矿型,结晶度较高。SEM谱图显示薄膜表面无明显开裂,粒子分布均匀,粒径约为20 nm。EDS测试结果表明薄膜材料中含有Cu元素,谱形一致。UV-Vis吸收光谱表明Cu掺杂以及Sn O2/Ti O2的复合使得在近紫外区的光吸收比纯Ti O2明显增强。光催化实验表明Cu掺杂后使得Sn O2/Ti O2复合薄膜对甲基橙的光催化降解效率进一步提高,Sn O2/Ti O2复合薄膜的光催化活性在10%Cu掺杂时达到最高。     

超声喷雾方法制备低辐射玻璃

利用超声喷雾方法在玻璃基板上喷涂SnO2：F薄膜，制备了低辐射玻璃(Low-E玻璃)．通过光谱测量，得到其可见光透过率为85％以上，在近红外波段出现高反射．利用四探针测量仪，测量其面电阻在2Ω／cm^2以下．扫描电镜测量结果表明膜的均匀性较好，平均颗粒直径约在50nm．利用等离子体截止波长理论，解释了低辐射玻璃红外反射的物理机制．     

喷雾热解法制备掺Cr的Al2O3薄膜及其抗腐蚀性能

用喷雾热解法制备出厚为２０００Ａ的掺Ｃｒ的Ａｌ２Ｏ３薄膜。ＸＲＤ和ＸＰＳ分析证明其为无定形的Ａｌ２－ｘＣｒｘＯ３（ｘ＝０．０７２），ＳＥＭ和椭圆仪分析结果验证了薄膜的均匀性。该薄膜表现出良好的绝缘性质和抗腐蚀性能。     

掺铁TiO2纳米薄膜的制备及光催化性能研究

采用溶胶-凝胶提拉法制备了掺铁改性TiO2纳米材料镀膜玻璃,研究了掺铁、PEG用量、镀膜层数等因素对TiO2纳米膜透光率和光催化降解性的影响,并对相关机理进行了探讨。研究发现,掺铁能提升TiO2纳米膜的光催化活性,催化降解速率为不掺铁时的1．38倍;溶胶前驱体中PEG用量为0．1g（0．13wt％）时制取的薄膜具有最佳的光催化活性和较好的透光率,低于或超过这个值,催化降解效果都不理想;镀膜层数为2～5层时,均有较高的透光率,光催化活性依次递增,其中综合效果最佳的为2层镀膜。纳米TiO2镀膜玻璃是一种性能优异的新型自净节能环保材料,在高楼建筑、灯具制造、城市照明系统等领域具有潜在的广泛用途。     

H_2气氛退火处理对Nb掺杂TiO_2薄膜光电性能的影响

采用电子束沉积方法,以钛酸锶(SrTiO3)为衬底制备铌(Nb)掺杂TiO2薄膜并研究后续H2气氛退火处理对其薄膜样品光电性能的影响.结果发现H2气氛热退火处理能有效改善Nb掺杂TiO2薄膜的导电率,最佳电阻率达到5.46×10-3Ω·cm,在可见光范围内的透光率为60%—80%.导电性能的改善与H2气氛退火处理后多晶薄膜的晶粒尺寸变大和大量的氧空位形成及H原子掺杂有关.     

微乳无机凝胶法制备掺杂纳米薄膜及其光催化性能研究

研究了用微乳无机凝胶法制备掺杂纳米薄膜及其光催化性能。得出了微乳液组分优化配比,在此基础上制备出ME-S2型自洁净玻璃;对制备出来的ME-S2型自洁净玻璃进行了实际废水除污性能试验、超亲水性试验, 测量了X射线衍射图谱。研究发现：ME-S2拥有较佳的光催化活性,镀膜玻片具有一定的自洁净功能,透光率的保持好于普通玻片, 还具有良好的超亲水性。     

铬掺杂氧化锌薄膜的超声喷雾法制备及其光学与磁学性质

用注射超声喷雾法将前驱体由针管直接送入超声喷头内,在石英基板上制备Zn_(1-x)Cr_xO(x=0.0,0.01,0.03,0.05)薄膜。采用X射线衍射仪、扫描电子显微镜、荧光光谱仪、紫外-可见分光光度计、振动样品磁强计(VSM)等对薄膜的结构、光学和磁学性质进行测量。实验结果表明,未掺杂的ZnO薄膜为六角纤锌矿结构,沿着c轴(002)择优取向,而Cr掺杂抑制了薄膜的c轴择优取向性;掺杂后的薄膜平均晶粒尺寸均增大,且当x=3%时,晶粒尺寸最大,达31.4nm。扫描电镜(SEM)下薄膜呈球形颗粒状,并且在x=5%下,薄膜出现了长条状的微观形貌。Cr掺杂使样品的光致发光谱(PL)发生了很大的变化:未掺杂的样品的PL谱在378nm处存在一个紫外发射峰,对应于550nm附近还存在一个由于缺陷态引起的绿光发射峰;掺Cr样品只有在350~550nm的很宽的范围内存在一个发射峰,对其进行高斯拟合后,发现掺Cr量为x=1%,3%,5%下样品均存在V_(Zn)(锌空位)、Zn_i(Zn间隙位)、V_(Zn)~-(带一个电子的锌空位)内部缺陷态,且当x=3%时,V_(Zn)最多。Cr的掺杂使得薄膜的带隙增大,并且x=3%时,禁带宽度最大,达到3.374eV。掺Cr的三个样品均具有室温铁磁性,且x=3%样品的磁化强度最大,其与V_(Zn)(锌空位)最大相对应,验证了Cr~(3+)和V_(Zn)的缺陷复合体是ZnO∶Cr样品具有稳定的铁磁有序的最有利条件的理论预测。     

Zn,Cu共掺杂的TiO_2:SnO_2薄膜的制备及性能研究

用溶胶-凝胶法制得Zn,Cu共掺杂的TiO_2∶SnO_2凝胶,旋转法于玻璃基底镀膜,制备出Zn,Cu共掺杂的TiO_2∶SnO_2薄膜,探讨了掺杂比例、煅烧温度对其结构、形貌和性能的影响。采用XRD、FTIR、FESEM、PL等测试技术对薄膜进行表征,并考察了其对甲基橙的光催化降解性能。结果表明:600℃时,薄膜粒子的结晶度较高,粒径小,分布均匀,表面平整且无明显裂痕;紫外-可见光谱(UV-Vis)表明:该薄膜在可见光区和紫外区都有很强的吸收;光催化性能测试表明:与纯相TiO_2对比,该样品对甲基橙的光催化降解率有较大提高,在最佳掺杂量比为n(Ti)∶n(Sn)∶n(Zn)∶n(Cu)=10∶3∶1∶1时,光催化降解率最高。     

Zr掺杂TiO_2薄膜的光学性能和光催化性能

为了研究TiO2禁带宽度和光吸收系数对其光催化性能的影响,利用电子束沉积方法在玻璃基底上制备了TiO2薄膜及Zr掺杂TiO2薄膜。采用拉曼光谱仪和分光光度计对膜的结构和吸收光谱进行了表征。研究结果表明:当退火温度为773K时,沉积得到的TiO2薄膜为锐钛矿结构薄膜;掺杂使TiO2禁带宽度变窄,吸收波长红移,在350~450nm附近光吸收系数增大,增强了TiO2的光催化活性。     

Mn doped ZnO nanostructured thin films prepared by ultrasonic spray pyrolysis method

Mn-doped ZnO thin films with different percentage of Mn content (0, 1, 3 and 5 at.%) and substrate temperature of 350 °C, were deposited by a simple ultrasonic spray pyrolysis method under atmospheric pressure. We have studied the structural and optical properties by using X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR) and ultra-violet visible near infrared (UV–Vis-NIR) spectroscopy. The lattice parameters calculated for the Mn-doped ZnO from XRD pattern were found to be slightly larger than those of the undoped ZnO, which indicate substitution of Mn in ZnO lattice. Compared with the Raman spectra for ZnO pure films, the Mn-doping effect on the spectra is revealed by the presence of additional peak around 524 cm⁻¹ due to Mn incorporation. With increasing Mn doping the optical band gap increases indicating the Burstein–Moss effect.     

Electrochromic and photoluminescence properties of cobalt oxide thin films prepared by spray pyrolysis

Cobalt oxide thin films were prepared by a facile spray pyrolysis technique, using a perfume atomizer with an aqueous solution of hydrated cobalt chloride salt with a molar concentration of 0.025?M as a source of cobalt. The films were deposited onto glass substrates at temperature of 350?°C. The structural, morphological, and electrochromic properties of the obtained films were studied. It was found from X-ray diffraction analysis that the films were polycrystalline in nature with spinel-type cubic structure and preferred orientation along [111] direction. The Scanning Electron Microscopy images revealed a porous structure with the average grain size around 200?nm. The cyclic voltammetry measurements revealed that Cobalt oxide thin film is an anodically coloring electrochromic material with a transmittance variation in the visible range of 31%, and a fast response time (about 2?seconds) and a good cycling stability. These electrochromic performances make cobalt oxide thin film an attractive material for using as an anodic electrochromic material in smart windows devices. The photoluminescence spectra exhibited a strong emission in the visible region confirming the good crystallinity properties of Co₃O₄ thin films.     

Effect of indium doping in CdO thin films prepared by spray pyrolysis technique

Preparation of transparent and conducting indium doped CdO thin films by spray pyrolysis on glass substrate is reported for various concentration of indium (2-8 wt%) in the spray solution. The electrical, optical and structural properties of indium doped CdO films were investigated using different techniques such as Hall measurement, optical transmission, X-ray diffraction and scanning electron microscope. X-ray analysis shows that the undoped CdO films are preferentially orientated along (2 0 0) crystallographic direction. Increase of indium doping concentration increases the films packing density and reorient the crystallites along (1 1 1) plane. A minimum resistivity of 4.843×10⁻⁴ Ω cm and carrier concentration of 3.73×10²⁰ cm⁻³ with high transmittance in the range 300-1100 nm were achieved for 6 wt% indium doping. The band gap value increases with doping concentration and reaches a maximum of 2.72 eV for 6 wt% indium doping from 2.36 eV of that of undoped film. The minimum resistivity achieved in the present study is found to be the lowest among the reported values for In-doped CdO films prepared by spray pyrolysis method.     

Preparation and characterization of transparent NiO thin films deposited by spray pyrolysis technique

Nickel oxide thin films were successfully fabricated with various deposition time (t_d = 5, 10, and 15 min) on glass substrates using spray pyrolysis technique. The deposited films undergo thermal treatment at 350 °C for various annealing time (t_a = 0, 15, 30 and 60 min). In this study, the effect of t_d and t_a on film thickness was observed and their influence on structural, morphological and optical properties were investigated. The films deposited with t_d = 5 min showed amorphous structure while the films grown at higher deposition time became partially crystallized with preferred growth along (1 1 1) direction. Heat treatment carried out in air allowed us to tune the polycrystalline structure and the diffraction intensity at preferred peak increases with the increase in t_a which is a consequence of better crystallinity. This was reflected in the AFM micrographs of the films which suggested that the thermal annealing (or increasing t_a) facilitates the process of grain-growth, and improves the crystalline microstructure. The optical transmission of the films was found to vary with t_d and t_a and thus film thickness. The thinner films show higher transparency in the UV–vis spectral region. The optical band gap was blue-shifted from 3.35 eV to 3.51 eV depending on t_a. The effect of t_a on the various optical constants of the NiO films has also been discussed.     

Physical properties of Pb doped ZnS thin films prepared by ultrasonic spray technique

In the present work, high quality Pb doped ZnS thin films were deposited on glass substrates at 450°C using spray ultrasonic technique. The dependence of the structural, morphological and optical properties of the films on the lead (Pb) doping amount was investigated by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), UV–vis–NIR spectrophotometry, and four-point method. The improvement of the obtained Pb:ZnS thin films properties were discussed as a function of Pb concentration (0.5 to 2 at.%). The average crystallite size of Pb:ZnS was found in the range of 25–37 nm. The scanning electron microscopy (SEM) reveals that the films are continuous, homogeneous and dense. The UV–vis–NIR spectroscopy characterizations demonstrated that all the films exhibit good transmittance (60–70%) in the visible region and their optical band gap energy ($E_{\mathrm{g}}$) changes from 3.92 to 3.6 eV. The films electrical resistivity showed an apparent dependence on Pb content.     

Effect of indium incorporation on properties of SnS thin films prepared by spray pyrolysis

Tin sulphide (SnS) thin films were deposited on glass substrate at different substrate temperature (T_s = 325 °C, 350 °C and 375 °C) by pyrolytic decomposition using stannous chloride and thiourea as precursor solutions. Also, indium-doped SnS thin films were prepared by using InCl₃ as dopant source. The dopant concentration [In/Sn] was varied from 2 at% to 6 at%. The XRD analysis revealed that the films were polycrystalline in nature having orthorhombic crystal structure with a preferred grain orientation along (1 1 1) plane. Due to In doping, the orientation of the grains in the (1 1 1) plane was found to be deteriorated. Atomic force microscopy (AFM) measurements revealed that the surface roughness of the films decreased due to indium doping. The optical properties were investigated by measuring the transmittance characteristics which were used to find the optical band gap energy, refractive index and extinction coefficient. The energy band gap value was decreased from 1.60 to 1.43 eV with increasing In concentration. The photoluminescence (PL) measurements of thin films showed strong emission band centered at 760 nm. Using Hall Effect measurements electrical resistivity, carrier concentration and Hall mobility have been determined.     

Quenching of photoconductivity in Fe doped CdS thin films prepared by spray pyrolysis technique

Fe doped CdS films are prepared using spray pyrolysis technique. All the samples are found to be of single phase and crystallized in hexagonal lattice. The X-ray diffraction peaks position of Cd_1−xFe_xS shifts to higher angle with increasing Fe concentration indicating decrease in cell volume. The temperature dependence of resistivity follows Arrhenius behavior having lower activation energy with increasing Fe concentration in dark while there is a little variation in light. Pure CdS films are having large photoconductivity. Upon Fe incorporation, this photoconductivity gradually decreases and for concentration more than 20%, it is almost vanished. Note worthy observation is the changes seen in morphology with AFM, viz. nanorod features seen in CdS is changed to continuous nanorod like structures depicting signatures of Ostwald ripening.     

Characteristics of CuInS2 thin films synthesizes by chemical spray pyrolysis

Optical and Quantum Electronics - In this paper, a variable-coefficient generalized nonlinear Schrödinger equation, which can be used to describe the nonlinear phenomena in the optical fiber,...     

Physico-chemical, optical and electrochemical properties of iron oxide thin films prepared by spray pyrolysis

Iron oxide thin films were prepared by spray pyrolysis technique onto glass substrates from iron chloride solution. They were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and (UV-vis) spectroscopy. The films deposited at T_s ≤ 450 °C were amorphous; while those produced at T_sub = 500 °C were polycrystalline α-Fe₂O₃ with a preferential orientation along the (1 0 4) direction. By observing scanning electron microscopy (SEM), it was seen that iron oxide films were relatively homogeneous uniform and had a good adherence to the glass substrates. The grain size was found (by RX) between 19 and 25 nm. The composition of these films was examined by X-ray photoelectron spectroscopy and electron probe microanalysis (EPMA). These films exhibited also a transmittance value about 80% in the visible and infrared range. The cyclic voltammetry study showed that the films of Fe₂O₃ deposited on ITO pre-coated glass substrates were capable of charge insertion/extraction when immersed in an electrolyte of propylene carbonate (PC) with 0.5 M LiCLO₄.     

Preparation and characterization of thin films of ZnO:Al by nebulized spray pyrolysis

Pure and Al-doped nanocrystalline ZnO films have been deposited on Si(100) substrate by nebulized spray pyrolysis. UV–NIR reflections, microstructure and electrical properties were investigated in some detail. The effects of Al doping and annealing at higher temperatures (1073 K) on these properties were investigated. The orientation and the microstructure were revealed by X-ray diffraction patterns and scanning electron microscopy (SEM). The resistivity of the films was inversely proportional to the intensity of the (002) peak. Also, as grain sizes increased, their mobility decreased; therefore, the resistivity value of the films became lower. The values of the non-linear I–V coefficient, , lay in the range 2–4 for all the samples. A great increase in the NIR reflectance (25 to 45%) was observed upon 0.3% Al doping. PACS 78.65; 78.50; 81.50; 78.2.-e