Zn-Se/不锈钢薄膜的电沉积及其应用研究

研究了Zn-Se/不锈钢薄膜的电沉积工艺条件及其在染料废水处理中的应用.讨论了电流密度、初始浓度比(c(ZnSO4):c(Na2SeO2))、pH值、柠檬酸钠加入量、电沉积时间、电沉积温度以及超声功率对镀层的影响.经扫描电镜及能谱仪分析测试表明,在电流密度为3.8mA/cm2、初始浓度比为250:1、pH=2.9、柠檬酸钠加入量为14.71g、电沉积时间为7min、电沉积温度为55℃、超声功率为160W条件下制备出的Zn-Se/不锈钢薄膜,其表面结晶致密、均匀,Zn与se的化学计量比为1:1.25.用所制备的薄膜材料作阴极,采用电化学复合技术处理罗丹明B模拟染料废水,可使模拟废水的脱色率接近99%,COD去除率接近90%.     

电沉积纳米ZnO薄膜

在硝酸锌溶液中电沉积ZnO，通过正交试验方法研究槽液浓度、pH值以及电流密度对纳米ZnO薄膜电沉积的作用。用XRD分析了纳米ZnO的组织、结构与成分，SEM获得了纳米ZnO的表面形貌。     

溶胶-凝胶法制备ZnO薄膜及其光催化性能

用溶胶-凝胶法在普通玻璃表面制备了薄膜型ZnO光催化剂,通过XRD、Ab2d、UV-VIS等测试技术对ZnO薄膜进行了表征;以偶氮胭脂红为降解物,考察了薄膜退火温度、镀膜层数、溶液初始质量浓度和反应体系初始pH值对ZnO薄膜光催化性能的影响,并进行了相关机理的探讨．研究表明：溶胶-凝胶法制备的ZnO薄膜呈透明状,薄膜表面均匀分布着球形ZnO晶粒;随着退火温度的升高,ZnO晶粒在17～30mm范围内逐渐增大．光催化实验中ZnO薄膜光催化降解偶氮胭脂红的最佳工艺条件是：退火温度为300℃,镀膜层数为5层,溶液初始pH值为8～9．     

电化学沉积法制备氧化锌薄膜及性能研究

以硝酸锌为原料,CTAB和硝酸钾为电沉积添加剂,以导电石墨板为对电极,采用方波电位沉积的方法在氧化锡铟（ITO）导电玻璃基底上制备出透明的ZnO薄膜,采用X射线衍射、原子力显微镜和光学透过谱等技术对不同沉积条件下薄膜的结晶特性、表面形貌、光学性质等进行了研究,结果表明,应用方波电位法制备氧化锌薄膜的优化条件为：沉积时间6min、Zn（N03）2、浓度0．05mol／L、沉积温度为80℃、退火温度500℃。制备的ZnO薄膜在可见光范围内的平均透光率〉85％,且表面平整度高,晶粒尺寸较小。     

衬底温度对ZnO薄膜生长过程及微观结构的影响研究

以醋酸锌水溶液为前驱体,采用改进的超声喷雾热解法在Si(100)衬底上沉积ZnO薄膜,以X射线衍射(XRD)、扫描电镜(SEM)等手段分析所得ZnO薄膜的晶体结构和微观形貌,着重考察了衬底温度对ZnO薄膜生长过程及微观结构的影响.结果表明,在衬底温度为500℃下所得ZnO薄膜表面均匀光滑,属六方纤锌矿结构,且沿c轴择优生长,晶粒尺寸的为40～50nm;衬底温度对ZnO薄膜生长过程影响显著,随衬底温度的升高,薄膜生长速率存在一极限值,且ZnO薄膜的c轴取向趋势增强,晶粒尺寸得到细化.     

透明致密ZnO薄膜的恒电流沉积及生长过程研究

采用阴极恒电流沉积方法, 以Zn(NO ₃)₂水溶液为电沉积液, 在经电化学预处理后的ITO导电玻璃上生长了具有c轴高度择优取向、均匀致密的透明ZnO薄膜. 采用X射线衍射、扫描电镜和光学透过谱等技术, 对不同沉积时间条件下薄膜的结晶特性、表面和断面结构、光学性质等进行了研究. 结果表明, 沉积时间对ZnO薄膜质量影响明显: 在薄膜生长后期(120min), ZnO薄膜的结晶性和表面平整度明显降低, 晶粒尺寸增大, 可见光透过率下降, 表明高质量ZnO薄膜的电化学沉积有一最佳生长时间; 此外, 薄膜厚度随时间呈线性变化, 表明可通过生长时间实现对ZnO薄膜厚度的精确控制.     

氧化锌薄膜的电化学沉积和表征

以铜片为衬底,用硝酸锌水溶液为电解液,采用阴极恒电流还原制备氧化锌薄膜.通过改变电流密度、电解液浓度、温度、离子掺杂等实验条件,系统研究了锌氧化物薄膜材料的电化学沉积过程.用X射线衍射、紫外-可见透射谱、热重-差热等技术对沉积物的结构、组成及光学性质进行了表征,结果表明,电沉积工艺条件显著影响薄膜材料的结构与组成.当电沉积产物中掺杂铜时,薄膜材料的光吸收边从375nm红移到458nm,带隙能从3.3eV降到2.7eV,拓宽了薄膜的吸光范围,这对ZnO薄膜在光学方面的应用具有重要意义.     

工艺参数对Ni-W-P-CeO2-SiO2纳米复合薄膜材料微观组织及性能的影响

通过Ni,W,P和CeO2,SiO2纳米颗粒的脉冲共沉积,在普通碳钢表面制备了Ni-W-P-CeO2-SiO2纳米复合薄膜材料,研究了电解液pH值和电解液温度对纳米复合薄膜材料电沉积过程的影响,采用化学组成、沉积速率、显微硬度和微观组织进行表征.结果表明:增加电解液pH值和电解液温度,纳米复合材料晶粒得到细化,沉积速率和显微硬度增加.当电解液pH值为5.5、电解液温度为60℃时,纳米复合薄膜材料晶粒细小,沉积速率最快,为28.87μm/h,显微硬度最高,为Hv673,若继续增加电解液pH值和电解液温度,沉积速率和显微硬度又开始降低.     

PI衬底上电沉积Cu薄膜的晶面择优取向

采用硫酸盐电沉积法,利用X射线衍射仪(XRD)、扫描电镜(SEM)等手段研究了不同电沉积条件下在PI膜表面制备的Cu薄膜的品而择优取向、平均晶粒尺寸及表面形貌.结果表明,沉积层的晶面择优取向受Cu薄膜厚度和电流密度影响,电流密度较小(0.2 A/dm2)和较大(3.5～5.5 A/dm2)时,电沉积Cu膜分别容易得到(111)和(220)晶面择优取向,较大电流密度有利于晶核的形成,薄膜表面平均颗粒尺寸较小.     

Mn、Co掺杂ZnO薄膜结构及发光特性研究

利用脉冲激光沉积(PLD)方法在Si(100)衬底上制备了ZnO、Zn0.8Mn0.2O、Zn0.8Co0.2O薄膜.薄膜的晶体结构和表面形貌采用X射线衍射仪和原子力显微镜测试.表明薄膜具有明显的c轴择优生长取向,薄膜表面较为平整,颗粒尺寸在纳米量级,薄膜中晶粒的生长模式为"柱状"模式.此外,Mn、Co掺入后,薄膜的X射线衍射峰有小角度偏移,这与 Mn2 、Co2 离子半径有关.PL谱显示Mn、Co掺杂ZnO薄膜的蓝、绿发光峰的位置相对纯的ZnO薄膜没有改变,还出现了紫外发光峰,其中Mn掺杂的蓝、绿光峰的强度减弱,Co掺杂的蓝光峰强度减弱,绿光峰强度增强.这是因为Mn、Co掺入改变了ZnO本征缺陷的浓度,发光峰的强度也随之而改变.     

Preparation of ZnO nanoparticles using electrodeposition and co-precipitation techniques for dye-sensitized solar cells applications

Zinc oxide thin films have been successfully prepared by co-precipitation and electrodeposition methods onto Fluorinated tin oxide substrate using zinc nitrate aqueous solutions at various bath temperatures (25–75 °C). The deposition of electrodeposition method was conducted using both using linear sweep voltammetry and Chronoamperometric techniques. The effects of solution composition, agitation and bath temperature on the electrochemical measurements and ZnO film characteristics were fully analyzed. The findings reveal that temperature and nitrate ion concentration have a strong promoting effect on ZnO film formation. Moreover, the obtained powders were investigated by X-ray diffraction, Field emission scanning electron microscopy and UV–Vis Spectroscopy. Structural characterization by X-ray diffraction indicates the formation of ZnO phase and the deposited film exhibits the Zincite structure with crystallite size around 51 nm. The photovoltaic performance of dye-sensitized solar cells based on both ZnO prepared by co-precipitation and electrodeposition methods was investigated. A power conversion efficiency (η) of 3.5 % was achieved for the DSSC with co-precipitation ZnO, which is higher than that of the cell with electrodeposition ZnO (2.5 %). Explanations are substantiated by incident photon to electron conversion efficiency curves.     

Preparation and characterization of bowl-like porous ZnO film by electrodeposition using two-dimensional photonic crystal template

A rapid and low-cost method combining electrodeposition with two-dimensional (2D) photonic crystal template technique to prepare large scale bowl-like porous ZnO films is described. The 2D photonic crystal templates were fabricated by self-assembly of monodispersed polystyrene (PS) microspheres on indium-tin-oxide coated glass substrates using spinning coating method. The interstitial spaces among the spheres of the templates were filled with ZnO via electrodeposition from an aqueous solution containing 0.02 M zinc nitrate as electrolyte under a constant potential of ?1.0 V at 65 °C for 10 min. After removal of the PS photonic crystal template, bowl-like porous ZnO film was obtained. The entire process can be accomplished within 30 min. Scanning electron microscopic images showed good homogeneity in morphology, X-ray diffraction spectra demonstrated the wurtzite structure of the obtained ZnO film, and transmission electron microscopy indicated the single-crystallinity of the ZnO. Ultraviolet–visible (UV–vis) spectrophotometer was used to detect the absorption in UV–vis region of the PS template, opal ZnO-PS composite and inverse opal ZnO respectively. Two strong emission bands at 400 and 550 nm were displayed in photoluminescence spectrum.     

NaCl-MnO2联合改性沸石对水中Zn2+的动态吸附

研究了NaCl-MnO₂改性沸石填料柱对水中Zn²⁺的动态吸附性能。探讨了填料厚度、Zn²⁺的初始质量浓度和流速对穿透曲线的影响。结果表明,NaCl-MnO₂改性沸石能有效去除水中的Zn²,填料层增厚,穿透曲线上的穿透点向右移动,穿透时间延长;而流速、Zn²⁺的初始浓度增大,穿透曲线上的穿透点向左移动,穿透时间缩短;用Thomas模型描述Zn²⁺初始质量浓度为50mg/L、滤速为4mL/min时改性沸石对Zn²⁺的吸附动力学,相关系数为0.9994,平衡吸附容量为12.04mg/g。     

Seed layer-free electrodeposition of well-aligned ZnO submicron rod arrays via a simple aqueous electrolyte

A potentiostatic electrodeposition technique was used to directly fabricate large-scale, well-aligned, and single-crystalline submicron ZnO rod arrays on tin doped indium oxide glass substrate without a pre-prepared seed layer of ZnO from an aqueous solution only containing zinc nitrate. The effects of electrochemical parameters, such as electrodeposition potential, electrodeposition duration, solution temperature, and precursor concentration, on the orientation, morphology, aspect ratio, and growth rate of ZnO rod arrays were systematically investigated. Results show that submicron ZnO rod arrays with (0 0 0 2) preferred orientation and perfect crystallization were obtained when electrodeposition potential was in the range from −0.6 to −1.1 V and solution temperature was controlled above 60 °C. Both high solution temperature and low precursor concentration resulted in the decrease in rod diameters. Photoluminescence measures showed that small diameter and nanotips of ZnO rod arrays should be responsible for strong and sharp ultraviolet emission in the room temperature photoluminescence spectra.     

Preparation of three-dimensional ordered macroporous Cu2O film through photonic crystal template-assisted electrodeposition method

Three-dimensional ordered macroporous (3DOM) Cu₂O film was prepared on indium-tin-oxide (ITO) glass using photonic crystal template-assisted electrodeposition approach. The technological process involved the following steps: preparation of three-dimensional (3D) photonic crystal template, potentiostatic electrodeposition of Cu₂O into the template, and template removal. 210 nm polystyrene (PS) spheres were used to prepare the 3D photonic crystal template by means of a vertical deposition technique on ITO glass. A two-electrode cell was used for electrodeposition, in which the anode was graphite and the cathode was PS-coated ITO glass. The electrodeposition solution consisted of 0.1 M sodium acetate and 0.02 M copper acetate and was acidified at pH 5.7. Via electrodeposition, the interstitial space of the packed PS photonic crystal template was filled with Cu₂O. After removal of the PS photonic crystal template by immersing in tetrahydrofuran solution, 3DOM Cu₂O film with a homogeneous area of 20 × 10 mm² was obtained. The film was characterized by field emission scanning electron microscopic (FE-SEM) and X-ray diffraction. The results indicated that the as-prepared Cu₂O film was of high purity, good homogeneity, and a well-ordered macroporous structure.     

Enhanced visible light response of ZnO porous thin film by post-annealing treatment

ZnO thin films were synthesized by a facile electrodeposition method in the aqueous solution. Porous ZnO thin films with wurtzite structure could be achieved by mean of annealing treatment. The growth mechanism of the porous ZnO thin film was discussed. The intensity of the E ₂ mode in the ZnO thin film, which represents crystalline quality of the thin film increases with the increasing of annealing temperature. Optical properties indicate that annealing temperature has strong effect on the optical band gap value and defect concentrations. Both the green and yellow emissions corresponding to respective oxygen vacancies and oxygen interstitials can be identified. The results show that ZnO annealed at 400 °C exhibits a significant photocurrent density enhancement which is about 18 times larger than that of the as-deposited ZnO thin films. The mechanism of the enhanced photoresponse for the ZnO thin film has been discussed in detail.     

原位生成法制备单分散的纳米氧化锌分散液

用ZnCl2作原料,PVP作分散剂,在160℃下采用原位生成法制得单分散、具有良好晶体结构和规则外形的ZnO纳米单晶分散液,用透射电子显微镜、X射线衍射、紫外/可见分光光度计等测试手段对其进行了表征.讨论了工艺条件对纳米ZnO尺寸和形貌的影响,并对其生长机理做了初步探讨.     

Structural analysis of vertically-aligned single crystalline ZnO nanorods grown on different seed layers with chemical solution deposition

We report the structural properties of the vertically-oriented ZnO nanorods fabricated on various ZnO seed layers with chemical solution deposition (CSD) technique. The ZnO nanorods were prepared using an aqueous solution with Zinc nitrate (Zn(NO3)2 x 6H2O, Aldrich) and hexamethylenetetramine (HMT, Aldrich) in a convection oven. A-plane sapphire substrates with a deposited ZnO thin film were placed upside down in a quartz holder to avoid any micro-crystalline contamination. Especially, our hydro-thermal syntheses are automatically processed on precision pump drive systems (Masterflex) to accurately control the pH of the aqueous solution. The [002] crystal orientation of the ZnO seed layer was observed by the X-ray diffraction pattern. Structural features of ZnO nanorods were systematically analyzed by scanning electron microscopy and tunneling electron microscopy, together with selective area electron diffraction patterns. Experimental observations clearly demonstrated the dependence of the growth direction of the ZnO nanorods on the crystal structures of the ZnO seed layers.     

Growth of highly oriented ZnO films by the two-step electrodeposition technique

Compact and transparent ZnO films were deposited on the ITO/glass substrates from zinc nitrate aqueous solution by the two-step electrodeposition technique. While the first potentiostatic step was used to produce ZnO seed layer, the ZnO film growth has been done galvanostatically. Effects of the potentiostatic parameters on the crystal structure, morphology and optical properties of ZnO films were investigated. Results show that ZnO films with highly c-axis preferred orientation can been obtained when the potentiostatic deposition at −1.2 V for 15 s has been applied. Such an observation might be attributed to the etching process of ITO substrate in the diluted HCl solution. The film exhibits smooth and compact morphology, high transmittance in the visible band (>80%) and sharp absorption edge (at ∼370 nm). The analysis on the growth mechanism indicates that the short potentiostatic process prior to the film growth can produce ZnO seed layer and substitute the initial nucleation process in the conventional one-step galvanostatic deposition, thus increasing the nucleation density and preventing the formation of loose structures.