Electrodeposition and characterization of Cu2O thin films using sodium thiosulfate as an additive for photovoltaic solar cells

Cuprous oxide(Cu_2 O) thin films have been grown by electrodeposition technique onto ITO-coated glass substrates from aqueous copper acetate solutions with addition of sodium thiosulfate at 60 ℃. The effects of sodium thiosulfate on the electrochemical deposition of Cu20 films were investigated by cyclic voltammetry and chronoamperometry techniques. Deposited films were obtained at-0.58 V vs. SCE and characterized by X-ray diffraction(XRD), Fourier transform infrared spectroscopy(FTIR), scanning electron microscopy(SEM), and optical, photoelectrochemical and electrical measurements. X-ray diffraction results indicated that the synthesized Cu20 films had a pure cubic phase with a marked preferential orientation peak along(200) plane and with lattice constants a = b = c = 0.425 nm. FTIR results confirmed the presence of Cu_2 O films at peak 634 cm~(-1) SEM images of Cu_2 O films showed a better compactness and spherical-shaped composition. Optical properties of Cu20 films reveal a high optical transmission(80%) and high absorption coefficient(α 10~4 cm~(-1)) in visiblelight region. The optical energy band gap was found to be 2.103 eV. Photoelectrochemical measurements indicated that Cu20 films had n-type semiconductor conduction, which confirmed by Hall Effect measurements.Electrical properties of Cu20 films showed a low electrical resistivity of 61.30 Ω·cm~(-1), carrier concentration of-4.94 × 10~(15)cm~(-3) and mobility of 20.61 cm~2· V~(-1)·s~(-1).The obtained Cu_2 O thin films with suitable properties are promising semiconductor material for fabrication of photovoltaic solar cells.     

Electrodeposition of ternary CuAgSe thin films: Use of the electrochemical quartz crystal microbalance approach for real-time phase quantification

A detailed electrochemical study of the ternary Cu + Ag + Se system on Pt substrate using the techniques of cyclic voltammetry (CV), hydrodynamic voltammetry at Pt-rotated disc electrode (RDE), anodic stripping has identified optimum conditions for the electrodeposition of ternary CuAgSe thin semiconductor films used as active membranes in developing Cu(II)-ion-selective sensors. A combined coulometry-quartz crystal microbalance (EQCM) protocol has been developed which allows real-time phase composition analysis of the target ternary CuAgSe and admixture with either Cu₂Se or Ag₂Se binary selenides. The EQCM data have provided valuable information concerning the mechanistic details of the CuAgSe-electrodeposition. The molar ratio of Cu:Se in the electrolytic bath is shown to be of crucial importance for depositing device quality films. Different mechanisms dominate when this ratio is increased from 1:5 to 1:1, from one-step diffusion-controlled electrochemical process (Cu:Se = 1:5) to a mixed electrochemical and chemical pathway for Ag⁺ assimilation (Cu:Se = 1:1).     

Fabrication of Super Hydrophobic Surfaces on Copper by Solution-immersion

Super hydrophobic copper wafer was prepared by means of solution immersion and surface self-assembly methods. Different immersion conditions were explored for the best hydrophobic surface. Scanning ele...     

铜表面超疏水界面的构建与调控(英文)

Super hydrophobic copper wafer was prepared by means of solution immersion and surface self-assembly methods. Different immersion conditions were explored for the best hydrophobic surface. Scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive spectrometer (EDS) and water contact angle measurements were used to investigate the morphologies, microstructures, chemical compositions and hydrophobicity of the produced films on copper substrates, respectively. Results show that the super hydrophobic surface is composed of micro structure of Cu 7 S 4 . The films present a high water contact angle larger than 150°, a low sliding angle less than 3°, good abrasion resistance and storage stability. The molecular dynamics simulation confirms that N-dodecyl mercaptan molecules link up with Cu 7 S 4 admirably, compared with Cu, which contributes to the stable super hydrophobic surface.     

Bio-synthesized palladium nanoparticles using alginate for catalytic degradation of azo-dyes

Palladium nanoparticles(PdNPs) were synthesized in a green way using sodium alginate functioning as both reductant and stabilizer. The formation of as-synthesized Pd NPs was supervised by Ultraviolet–visible(UV–Vis)spectroscopy and confirmed by the surface plasmon resonance(SPR) band. The effect of several synthesis factors such as precursor ratio, solution p H, reaction time, and temperature were investigated by the factorial design of experiments in order to optimize the experimental conditions. The optimal synthesis parameters were achieved by heating 1.0 ml of 1.0% sodium alginate(SA), 3.0 ml of 10~(-2) mol·L~(-1) H_2PdCl_4 at 80 °C for a period of 30 min in a neutral reaction medium(pH = 6). High-resolution transmission electron microscope(HRTEM), energy dispersive X-ray(EDX) spectroscopy, selected area electron diffraction(SAED) pattern, X-ray powder diffraction(XRD),and dynamic light scattering(DLS) were used to confirm the uniform spherical shapes and high crystallinity of Pd NPs with average particle size of(2.12 ± 1.42) nm. The SEM images show the distribution of Pd NPs presented among the SA. FTIR spectra indicate that SA is a good capping agent to stabilize Pd NPs for a long time. The catalytic degradation of model azo-dyes such as mono-azo(Cibacron Yellow FN–2R) and di-azo(Cibacron Deep Red S–B) were confirmed the catalytic activity of Pd NPs. The Pd NPs can accelerate the degradation rate by more than 80 and 10 times respectively as confirmed by kinetics constant(k) values.     

有序介孔CuCoZr催化剂的制备及其催化合成气制乙醇及高级醇性能

改性费托合成催化剂(尤其是CuCo催化剂)在合成气制乙醇及高级醇反应中具有高的催化活性和总醇选择性,被认为是潜在的工业催化剂。采用蒸发诱导自组装(EISA)法和共沉淀(CP)法制备了一系列CuCoZr催化剂,考察了制备方法及EISA法制备的催化剂Cu/Co原子比对合成气制乙醇及高级醇性能的影响。采用N₂物理吸附-脱附、小角X射线衍射(XRD)、原位XRD、透射电镜(TEM)、H₂-程序升温还原(TPR)、CO-程序升温脱附(TPD)和原位红外漫反射光谱(DRIFT)对催化剂进行表征,分析了合成气在Cu/Co原子比为3∶1的Cu₃Co₁Zr催化剂表面的反应路径。结果表明,EISA法制备的Cu Co Zr催化剂为有序介孔结构,比表面积随Cu/Co原子比的增加先增大后减小,其中Cu₃Co₁Zr催化剂比表面积和CO吸附量均为最大,分别为143m²/g和0.33mmol/g,催化剂的Cu晶粒尺寸仅为9.1nm。在催化合成气制醇的反应中CO转化率...     

Cu2O/TiO2催化甲醛乙炔化反应的载体效应

以不同温度焙烧的TiO₂为载体,CuCl₂·2H₂O为铜源,NaOH为沉淀剂,L-抗坏血酸钠为还原剂,采用液相还原-沉积沉淀法制备了Cu₂O/TiO₂,借助X射线粉末衍射（XRD）、H₂程序升温还原（H₂-TPR）、N₂-物理吸附、透射电镜（TEM）、X射线光电子能谱（XPS）等手段,研究了TiO₂载体焙烧温度对Cu₂O/TiO₂甲醛乙炔化反应性能的影响。结果表明,低温焙烧得到的TiO₂载体以锐钛矿相存在,与Cu₂O物种间具有弱的相互作用,使得Cu₂O被过度还原为金属Cu,催化活性较低。随着载体焙烧温度的升高,TiO₂中出现金红石相,Cu₂O与载体间相互作用增强,Cu₂O高效转变为乙炔亚铜活性物种,使催化剂表现出最佳的催化性能。     

铜基石墨烯复合催化剂的合成与表征

采用原位水热法制备了Cu/r GO催化剂并引入对苯二甲酸(TPA)对Cu基石墨烯复合材料进行改性研究,探究了不同溶剂、水热时间、沉淀p H对引入TPA的Cu/r GO催化剂材料微观结构特性的影响。通过XRD、FT-IR、XPS和SEM表征技术分析了催化剂的形貌结构及物化性质。考察了催化剂用于二乙醇胺脱氢的催化性能。在V(乙醇)∶V(水)=1∶1为溶剂,沉淀p H为13.0,160℃水热10 h,制备的催化剂性能最好,亚氨基二乙酸收率为86.55%,与没有添加TPA的Cu/r GO催化剂相比收率提高20%。TPA的加入,增强了GO片层间的相互作用,增加了GO片层间的有机官能团,稳定Cu2O并使其结晶度较好,增加催化剂活性位点,以提高反应速率。且粒径约为10 nm左右的Cu纳米粒子均匀分布在褶皱状片层结构的r GO表面,提高催化剂抗烧结性能。     

pn型Cu2O/CdS纳米线的制备及性能

采用电沉积法,在AAO模板中成功制备出pn型Cu₂O/CdS纳米线阵列。利用扫描电子显微镜（SEM）、透射电子显微镜（TEM）和X射线衍射分析（XRD）对样品的形貌和结构进行表征,利用光照开路电位测试和光吸收光谱测试对Cu₂O/CdS纳米线的性能进行了研究。纳米线的直径约100 nm,与AAO模板孔径相同,XRD结果表明Cu₂O/CdS纳米线由立方晶系的Cu₂O和立方晶系与六方晶系混合晶系的CdS组成。Cu₂O/CdS纳米线的光响应性能增强。在Xe灯照射下Cu₂O/CdS纳米线表现出良好的光催化性能,光照7 h后,Cu₂O/CdS纳米线对罗丹明B的降解效率达到66.02%。     

CuNi纳米晶的可控合成及Pt/CuNi催化剂催化肉桂醛加氢性能

采用水热法制备了CuNi二元金属纳米晶。以水合肼为还原剂,探究水热合成温度、表面活性剂[乙二胺（EDA）、聚乙烯吡咯烷酮（PVP）、十六烷基三甲基溴化铵（CTAB）]对CuNi纳米晶形貌的影响。随水热合成温度的升高（60℃、90℃、120℃、150℃）,Cu²⁺、Ni²⁺的还原速率加快,有利于形成Cu@Ni核壳结构。以EDA为表面活性剂时,制备的CuNi二元金属纳米晶在120℃和150℃时分别呈现花状和海胆状。此外,以CuNi纳米晶为催化剂载体,采用化学置换法负载贵金属Pt合成了Pt/CuNi三元金属催化剂。X射线粉末衍射（XRD）、扫描电子显微镜（SEM）、扫描电镜X射线能谱（SEM-EDS）、X射线光电子能谱（XPS）、高角度环形暗场扫描透射（HAADF-STEM）和元素面扫（STEM-EDS）表征结果表明,Pt/CuNi催化剂纳米结构为小岛状的Pt纳米团簇负载于CuNi纳米晶。其中,Pt/CuNi-120-EDA（120为水热合成温度,EDA为制备CuNi纳米晶时添加的表面活性剂）催化剂表面具有较丰富的缺陷位和活性位点,使其在肉桂醛加氢反应中表现出最佳的催化性能（80℃下对苯丙醇的产率达100%）。     

Fe2O3/改性沸石催化剂的制备及其催化臭氧氧化对氯苯酚

为了提高非均相催化臭氧氧化体系处理难降解有机废水的效率,分别以十六烷基三甲基溴化铵（CTMAB）改性的天然沸石和Fe(NO₃)₃·9H₂O溶液作为载体和活性组分前体,采用浸渍法制备Fe₂O₃/改性天然沸石催化剂（MNZ）,利用能谱仪（EDS）、扫描电镜（SEM）、傅里叶变换红外光谱仪（FTIR）、X射线衍射仪（XRD）、X射线光电子能谱仪（XPS）、N₂-吸附/脱附等方法分析催化剂的结构和组成,研究其催化臭氧氧化对氯苯酚的效果和催化机制。结果表明：Fe₂O₃/MNZ催化剂保持了天然沸石的表面结构。Fe₂O₃均匀负载在沸石表面,属于典型的分子筛结构,比表面积、孔容和孔径分别为12.776m²/g、0.042cm³/g和3.932nm。在对氯苯酚初始浓度为100mg/L、臭氧浓度为2.6mg/L、温度为25℃、pH为7.0±0.2的条件下,对氯苯酚和化学需氧量（COD）去除率分别为87.26%和48.83%。天然沸石与Fe₂O₃共同促进臭氧分解生成强氧化能力的羟基自由基（·OH）,提高了对氯苯酚的去除率,反应体系遵循羟基自由基作用机理。     

Underlying mechanism of the hydrothermal instability of Cu3(BTC)2 metal-organic framework

Water induced decomposition of Cu₃(BTC)₂ (BTC= benzene-1,3,5-tricarboxylate) metal-organic framework (MOF) was studied using dynamic water vapour adsorption. Small-angle X-ray scattering, Fourier transform infrared spectroscopy and differential scanning calorimetry analyses revealed that the underlying mechanism of Cu₃(BTC)₂ MOF decomposition under humid streams is the interpenetration of water molecules into Cu-BTC coordination to displace organic linkers (BTC) from Cu centres.     

Synthesis of spinel ferrite and its role in the removal of free fatty acids from deteriorated vegetable oil

Deterioration and loss of quality of vegetable oil is a big challenge in the food industry. This study investigated the synthesis of nickel ferrite (NiFe₂O₄) via co-precipitation method and its use for the removal of free fatty acids (FFAs) in deteriorated vegetable oil. NiFe₂O₄ was characterized using Fourier transformed infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric (TG) analysis, Brunauer–Emmett–Teller (BET) surface area, transmission electron microscopy (TEM), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). Synthesis of NiFe₂O₄ was confirmed by characterization, which revealed a BET surface area of 16.30 m²·g^-1 and crystallite size of 29 nm. NiFe₂O₄ exhibited an adsorption capacity of 145.20 L·kg^-1 towards FFAs with an 80.69% removal in a process, which obeys Langmuir isotherm and can be described by the pseudo-second-order kinetic model. The process has enthalpy (ΔH) of 11.251 kJ·mol^-1 and entropy (ΔS) of 0.038 kJ·mol^-1·K^-1 with negative free energy change (ΔG), which suggests the process to be spontaneous and endothermic. The quantum chemical computation analysis via density functional theory further revealed the sorption mechanism of FFAs by NiFe₂O₄ occurred via donor–acceptor interaction, which may be described by the lowest unoccupied molecular orbital (LUMO) and the highest occupied molecular orbital (HOMO). The study showed NiFe₂O₄ to be a potential means that can remove FFAs from deteriorated vegetable oil.     

炭化活化条件对Cu/AC表面Cu价态及其催化降解苯酚的影响

采用前体浸渍法研制了生物质基载铜活性炭催化剂（Cu/AC）,利用N₂-吸附脱附、X射线光电子能谱等技术对Cu/AC性质进行了表征,在固定床反应器中研究了不同炭化活化条件所得Cu/AC催化湿式氧化降解苯酚性能。结果表明：Cu/AC表面Cu物种以Cu²⁺和（Cu⁺+Cu⁰）共存。随着制备Cu/AC炭化温度的升高,炭化过程中产生更多的挥发分,促进Cu²⁺还原为Cu⁺和Cu⁰,（Cu⁺+Cu⁰）含量增大,Cu/AC降解苯酚催化活性逐渐升高;随着炭化时间延长,（Cu⁺+Cu⁰）含量下降,Cu₂O、CuO较好地并入载体使晶格氧含量增加,催化活性先升高后下降;随着活化温度升高和活化时间延长,Cu/AC比表面积达到1096.1m²/g并有大量微孔生成,大量含氧官能团分解将炭化过程中还原生成的（Cu⁺+Cu⁰）氧化为Cu²⁺,晶格氧含量增加,催化活性随着活化温度的升高而升高,随着活化时间的延长先升高后下降。催化湿式氧化降解苯酚过程中,Cu/AC具有良好的稳定性和低的Cu离子浸出浓度。Cu/AC的最优制备条件为炭化温度800℃,炭化时间2h,活化温度880℃,活化时间为2h,所得Cu/AC在反应8.5h时实现98.5%的苯酚转化率和91.1%的COD转化率。     

Oxidic precursors of molybdena supported on nickel and magnesium aluminate hydrotreating catalysts

The oxidic precursors of molybdena-based hydrotreating catalysts have been prepared using nickel and magnesium aluminates and characterized by laser Raman spectroscopy (LRS) and X-ray photoelectron spectroscopy (XPS). Three series of supports (80, 120 and 140 m².g⁻¹) have been investigated. Their aluminate spinel structure was confirmed both by X-ray diffraction (XRD) and LRS. Nickel oxide and magnesia have also been detected on the low surface area systems. In both series, a surface deficit of the foreign cation has been observed relative to the Al³⁺ of the aluminate phase. This deficit was more pronounced for Ni²⁺. Deposition of molybdate species does not modify the surface composition of these supports and a monolayer-like coverage up to 4.5 to 5 Mo at.nm⁻² was obtained. Nickel added by impregnation was shown to interact with the supported oxomolybdate species, whereas the nickel of the support does not. These investigated supports closely resemble γ --- Al₂O₃ in the preparation of hydrotreating catalysts.     

微反应器共沉淀反应制备铜锰催化剂

在Caterpillar微反应器中采用共沉淀法制备了不同铜锰比的共沉淀物,直接焙烧得到铜锰复合氧化物催化剂。采用X射线衍射(XRD)、热重分析(TG)、拉曼光谱(Raman)和X射线光电子能谱(XPS)对沉淀物和催化剂进行了物相和结构分析。结果显示,随着Cu含量的增加,催化剂中Mn³⁺所占比例逐渐下降,表面晶格氧含量呈现先上升后下降的趋势,催化甲苯降解的活性呈现先上升后下降的规律。微反应器中的流动反应特性使得催化剂中的Cu、Mn保持良好分散性,有利于提高催化剂中Mn³⁺含量,此时表面晶格氧成为催化活性的制约因素。     

New route for synthesizing Mn-silicalite-1

Mn-silicalite-1 (Mn_5.2Si_90.8O₁₉₂) was synthesized from Mn²⁺ ion-exchanged magadiite. The characteristics of Mn-silicalite-1 were investigated using electron spin resonance, synchrotron X-ray powder diffraction, IR spectroscopy and chemical analysis. The measurements indicate that Mn²⁺ ions replace Si in the silicalite-1 framework. The orthorhombic framework structure of calcined Mn-silicalite-1 has been determined. The space group is Pnma, with a=20.1017(3) Å, b=19.8826(4) Å, c=13.3758(3) Å.     

Shape selectivity of trace by-products for supercritical water oxidation of 2-chlorophenol effected by CuO/ZSM-48

Shape selectivity of trace by-products in supercritical water oxidation (SCWO) of 2-chlorophenol (2CP) catalyzed by CuO/ZSM-48 has been investigated. Experimentally, destruction efficiency of 2CP in the SCWO process is effectively enhanced by CuO/zeolite catalysts. In the two-dimensional (2D) channels of ZSM-48, formation of undesired by-products such as polycyclic aromatic hydrocarbons (PAHs) and higher chlorinated phenols (via the Cl-reinsertion) is extremely suppressed in the SCWO of 2CP compared to those observed for zeolites ZSM-5 and Y with three-dimensional (3D) channel structure and larger pore sizes, respectively. The main oxidation active species on CuO/ZSM-48 surfaces were CuO and Cu₂O determined by X-ray photoelectron spectroscopy (XPS). Ratios of the surface species CuO/Cu₂O are between 13.4 and 14.1 in the SCWO process. However, the existence of the Cu–O and Cu–Cu species with a Cu–O/Cu–Cu ratio of 3.5 in the copper catalyst is also observed by extended X-ray absorption fine structure (EXAFS) spectroscopy. Furthermore, since the absence of Cu–Cl species in the XPS and EXAFS spectra, one would suggest that copper in the channels of ZSM-48 is unlikely involved in the abstraction of Cl species from 2CP in the SCWO process.     

Thermal Decomposition of Europium Hydroxide

The thermal decomposition of europium hydroxide in an air atmosphere was investigated by means of weight-loss measurements, infrared spectroscopy, X-ray diffraction analysis, and electron microscopy. These studies showed that EU(OH)° decomposed at temperatures between 225° and 300°C into EuOOH, which was stable up to about 425°C. Between 435° and 465°C this compound decomposed into cubic Eu₂O₃, which was stable until its inversion to the high-temperature monoclinic form. X-ray diffraction data were collected for Eu(OH)₃ and EuOOH and showed that the trihydroxide has a hexagonal crystal structure and the oxyhydroxide is possibly orthorhombic. The Eu(OH)₂, EuOOH, and cubic EunOa powders contained particles up to several microns in size consisting of agglomerates of crystallites in the size range 200 to 400 A. The single monoclinic Eu₂O₃ sample studied contained crystallites whose average size was greater than 2000 A.     

水热法制备氧化钴/泡沫镍材料及电容性能分析

利用简单的水热法制备出不同反应液浓度、不同反应时间以及不同反应温度氧化钴/泡沫镍（CoO/NF）电极，旨在改善氧化钴材料的比电容及稳定性。通过XRD、SEM、TEM、EDS Mapping和BET对其结构和形貌进行了表征，同时在1mol/L氢氧化钾（KOH）电解液中采用循环伏安曲线（CV）、充放电曲线（CP）、循环性能测试、大电流充放电测试以及交流阻抗（EIS）测试研究了其电化学性能。表征结果显示氧化钴均匀地分布在泡沫镍载体表面，且片状结构CoO-8h/NF具有较大的比表面积和多孔特性。在三电极体系中，电化学测试结果显示CoO-8h/NF在1mA/cm²电流密度下表现出最好的电容性能，比电容可以达到930mF/cm²。在10mA/cm²电流密度下对CoO-8h/NF电极进行10000次恒电流充放电测试，循环测试后电极的比电容几乎没有衰减，具有较好的稳定性，是超级电容器比较理想的正极材料。