能量过滤磁控溅射技术制备Cu2O/TiO2复合薄膜及其光催化性能

目的制备具备良好光催化性能的Cu_2O/Ti O_2叠层复合薄膜。方法利用直流磁控溅射技术(DMS)和能量过滤直流磁控溅射技术(EFMS)在玻璃基底上制备Cu_2O/Ti O_2叠层复合薄膜,利用扫描电镜(SEM)、X射线衍射(XRD)、椭偏仪和光催化测试系统表征和分析了薄膜的表面形貌、结构、透射率和光催化性能。结果 DMS技术和EFMS技术制备的Ti O_2和Cu_2O薄膜都有良好的结晶特性,其中Ti O_2为单一的锐钛矿结构。相对于DMS技术制备的Cu_2O薄膜,EFMS样品中的Cu_2O薄膜的衍射峰较弱,而且衍射峰的宽度变宽,衍射曲线比较平滑。薄膜表面较平整,颗粒均匀,较细小,边界明显。DMS和EFMS两种技术制备的薄膜的平均晶粒直径分别为15.4 nm和10.8 nm。透射光谱测试结果表明,EFMS技术制备的复合薄膜平均透射率较大,在350～800 nm范围内,平均透射率为0.388,DMS薄膜的值为0.343。对罗丹明B(Rh B)的光催化降解结果表明,EFMS技术制备的薄膜的降解速率为-0.00411,大于DMS技术制备的薄膜的降解速率-0.00334。结论 EFMS技术制备的Cu_2O/Ti O_2叠层复合薄膜对罗丹明B具有较大的光催化降解速率。     

旋转磁场对海水中铜流动腐蚀的影响(英文)

通过实验室中12d的旋转电磁腐蚀实验,研究海水中铜的流动腐蚀。利用扫描电镜和X射线能量分散分析系统(SEM/EDAX)和X射线衍射仪(XRD)分析铜试样的表面微观结构和相组成,包括空干后腐蚀产物膜中的Cu2O和CuO的组成。结果表明:流动腐蚀过程是坑蚀、扩展、腐蚀产物膜和表面产物溶液,最后是坑蚀。旋转电磁场抑制了铜在海水中的流动腐蚀。     

Optical and Photocatalytic Properties of Cu-Cu2O/TiO2 Two-Layer Nanocomposite Films on Si Substrates

通过磁控溅射法在TiO2薄膜上生长Cu-Cu2O复合层,从而制备新型Cu-Cu2O/TiO2双层纳米复合薄膜。并采用X射线衍射（XRD）,扫描电子显微镜（SEM）,荧光光谱（PL）,X射线光电子能谱（XPS）和紫外可见漫反射光谱（DRS）等方法对膜的结构,形态和光学性能进行了研究。X射线衍射谱表明,Cu-Cu2O混合物层和Cu2O层都没有影响TiO2的结晶相。XPS结果表明,Cu的存在抑制了Cu2O表面在空气中的氧化。SEM分析表明,结晶良好的Cu-Cu2O混合物微小纳米颗粒均匀分散于TiO2表面。由于紫外可见漫反射光谱的Cu-Cu2O/TiO2复合薄膜的吸收边发生红移。PL光谱证实了在Cu的存在下,激发电子和空穴的复合率降低。光催化实验表明,与纯Cu2O/TiO2相比,所制备的Cu-Cu2O/TiO2-8显示出更高的光生载流子效率,其光催化性能也显著提高。此外,还对Cu-Cu2O/TiO2-8光催化活性增强的原因进行了讨论     

均相沉淀模板法制备纳米Y2O3空心球研究

以粒径约150 nm的碳球为模板,通过均相沉淀法制备出Y(OH)3/碳球复合微球,煅烧除去碳球模板,得到粒径约300 nm的纳米Y2O3空心球。通过傅里叶红外光谱(FT-IR)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线衍射(XRD)和热失重分析(TG)以及X射线光电子能谱(XPS)等测试手段表征复合微球和纳米Y2O3空心球的形貌和结构。结果表明:空心球由立方晶系纳米Y2O3构成,粒径约为300 nm,壳厚度约为20 nm。     

Al掺杂TiO2介孔材料的合成、表征和光催化性能

以钛酸四丁酯为钛源、十八水硫酸铝为铝源、三乙醇胺为模板剂,采用研磨-溶胶技术合成了Al掺杂的TiO2介孔材料,并利用XRD、EDS、TEM、BET、UV-vis和IR等手段表征了材料的结构、形貌、比表面积、孔径分布及光学性能.结果表明:Al掺杂能够减小TiO2光催化剂的粒径,提高介孔TiO2的热稳定性;Al掺杂TiO2介孔材料的平均孔径为4.5 nm,比表面积达到110.2 m2/g;相比商用P25和介孔TiO2,Al掺杂介孔TiO2的吸收边发生红移,对初始浓度为20 mg/L的甲基橙进行催化降解1h后,其降解率达到92.5％.     

Cu_2O-Cu复合材料制备工艺的研究

以Cu_2O和炭黑粉末为原料,采用原位还原-无压(热压)烧结工艺制备Cu_2O-Cu复合材料.利用XRD和OM对烧结试样进行研究,并测试其力学性能.研究表明,复合材料由Cu和Cu_2O两相组成,原位还原-无压烧结法的合理烧结时间为5 h,其力学性能高于传统粉末冶金法制备复合材料力学性能,抗压强度464 MPa.原位还原-热压烧结法可以改善试样致密性及细化微观组织,进一步提高力学性能,抗压强度达到702 MPa.     

Primary study of the isothermal phase diagram of the Cu2O-Al2O3-SiO2 ternary system at 1150℃ in air

The isothermal phase diagram of the Cu2O-Al2O3-SiO2 ternary system at 1150℃ was reported for the samples which were prepared from sol-gel method and quenched by water after being heated at 1150℃ for 12 h. Based on the conventional X-ray powder diffraction (XRD) and in situ high-temporature XRD quantitative analysis, in addition to scanning electron microscopy measurement, the phase identification was achieved. Combining the deduction from the component phase diagrams of the binary systems using the phase equilibrium theorem, the primary isothermal phase diagram was plotted over the composition area Cu2O-mullite-SiO2. In this area, the approximate composition areas of two two-phase regions and one three-phase region, (L2 + Cr), (L2 + M), and (L1 + L2 + Tr), were determined. Moreover, the precise composition areas of both of the three-phase regions (L2 + Cr + M) and (L2 + M + A) were determined according to the results of conventional and in situ high-temperature XRD quantitative analysis by Rietveld method.     

纳米Cu_2O/Ag/TiO_2三层复合薄膜的结构及性能

通过磁控溅射方法制备了一种新颖的纳米Cu2O/Ag/Ti O2三层复合薄膜。用X射线衍射(XRD)仪、扫描电子显微镜(SEM)、紫外可见分光光谱仪(Uv-vis)和荧光光谱仪(FLO)对薄膜的晶体结构、表面形貌、光学性能及Ag金属中间层的存在对复合薄膜的影响进行了分析。此外,对薄膜光催化性能的研究表明,插入Ag层的纳米Cu2O/Ag/Ti O2三层复合薄膜显示出远高于Cu2O/Ti O2双层复合薄膜的可见光催化活性。催化性能的提高归因于Ag金属中间层的存在,提高了三层复合薄膜的可见光吸收强度,增加了表面积,促进了激发电子的转移及光生电子和空穴的分离。     

泡沫铜表面改性对化学气相沉积高质量泡沫金刚石的影响

目的选择合适的过渡层材料改善三维连通泡沫铜衬底与金刚石之间的结合性,制备出三维连通结构的泡沫金刚石。方法选择三维连通的泡沫铜作为衬底,使用磁控溅射技术在其表面沉积Ti、Cr过渡层,然后通过热丝化学气相沉积技术(HFCVD)在表面改性后的泡沫铜衬底上沉积金刚石涂层。通过扫描电子显微镜(SEM)、能谱分析仪(EDS)、拉曼光谱仪及红外热成像仪等仪器,对样品的表面/截面形貌、成分结构及热扩散性能进行检测与分析。结果经过Ti、Cr过渡层改性后,泡沫铜表面均能沉积出连续致密的高质量金刚石涂层,在相同的CVD沉积参数下,Cr过渡层泡沫金刚石(Cu-Cr/Dia)的晶粒尺寸更大(~5μm),晶粒质量更高,且膜层厚度大于Ti过渡层泡沫金刚石(Cu-Ti/Dia),Cu-Ti/Dia与铜衬底的结合性要优于Cu-Cr/Dia。Cu-Cr/Dia和Cu-Ti/Dia的热扩散性能均优于泡沫铜,其中Cu-Cr/Dia的热扩散能力略高于Cu-Ti/Dia。结论镀覆Ti、Cr过渡层有效增强了金刚石与泡沫铜衬底之间的界面结合,成功制备了三维连通结构的泡沫金刚石。     

Synthesis and characterization of cuprous oxide dendrites: New simplified green hydrothermal route

Cuprous oxide (Cu₂O) dendrites were prepared by simple hydrothermal route at two different temperatures using starch as reducing and stabilizing agent. Scanning Electron Microscopy (SEM) revealed the alterations in morphology with reaction temperature and time. The spherical nanoparticles obtained at lower reaction temperature self-assembled into distinct dendritic nanostructures at high temperature. The mechanism of formation of dendrite over the polysaccharide template has been discussed. Transmission Electron Microscopy (TEM) revealed that the crystalline size of these dendrites in one dimension is about 50 nm. The nanoparticles were characterized by UV-vis and photoluminescence (PL) spectroscopy, X-ray diffraction (XRD), FT-IR and Thermal Gravimetry Analyzer (TGA). Impedance analysis of the nanostructures showed conductivity to be a function of temperature.     

Effect of surface free energy of acetylene black powder on air electrode performance

The effects of acetylene black powder surface free energy on air electrode electrochemical performance and lifetime were studied. The acetylene black was immersed in 30% H2O2 at room temperature and the changes of functional groups and surface free energy were investigated by X-ray Photoelectron Spectroscopy (XPS) and powder contact angle (CA). The air electrode performance was characterized by the potential polarization curves and the lifetime was measured by constant-current discharge. It shows that, its surface free energy is the lowest when the acetylene black is immersed in H2O2 for 240 h. The polarization potential of the air electrode prepared by the pretreated acetylene black is 0.25 V(vs. Hg/HgO), 0.21 V lower than the air electrode with untreated acetylene black when the working current density is 100 mA·cm-1 . And its lifetime is over 800 h at 80 mA·cm-1 . The pretreatment of acetylene black for proper time by H2O2 is favorable for the stability of the tri-phase reaction interface of air electrode and improvement of its performance.     

等离子复合处理制备光催化N掺杂TiO2薄膜（英文）

通过等离子合金化技术在不锈钢表面制备TiN薄膜,然后对TiN薄膜进行热氧化得到N掺杂TiO2薄膜。同时制备 TiO2薄膜作为对比研究。利用X射线衍射(XRD)、X射线光电子能谱(XPS)、扫描电子显微镜(SEM)及紫外-可见分光光度仪(UV-Vis)对得到的薄膜进行表征。XRD测试结果表明:经过450 °C氧化处理的薄膜中存在锐钛矿晶型的TiO2。经热氧化后薄膜表面均匀分布着尺寸接近的微小凸起物。TiO2和N掺杂TiO2的带隙分别为3.25eV和3.08eV。可见光下薄膜催化剂降解亚甲基蓝溶液的实验结果表明:N 掺杂TiO2薄膜比未掺杂TiO2薄膜的光催化效率明显高,可见光照射150min后对亚甲基蓝溶液的最终降解率为20%。     

Influence of calcination atmosphere on photocatalytic reactivity of K2La2Ti3O10 for water splitting

The layered perovskite type oxide K2La2Ti3O10 powders were prepared under air, Ar and H2 calcination atmospheres by sol-gel method and characterized by X-ray diffractometry, UV-Vis diffuse reflectance and X-ray photoelectron spectroscopy. The influence of the calcination atmosphere on the photocatalytic reactivity of K2La2Ti3O10 for hydrogen production was investigated. The photocatalytic reactivity of K2La2Ti3O10 prepared under air, Ar and H2 atmospheres was compared with that prepared under ultraviolet and visible light radiation using Г as electronic donor. The results show that K2La2Ti3O10 prepared under Ar and H2 atmospheres has higher photocatalytic activity for hydrogen production than that prepared under air atmosphere. The hydrogen production rates under ultraviolet irradiation are 127.5, 81.3 and 57.0 μmol/（L·h） and those under visible light irradiation are 40.2, 30.2 and 16.5 μmol/（L2h） respectively when K2La2Ti3O10 is prepared under Ar, H2 and air atmospheres.     

通过水溶液还原法用抗坏血酸制备纳米铜颗粒(英文)

通过水溶液还原法用抗坏血酸还原Cu2+制备纳米铜颗粒,并研究溶液pH和Cu2O平均粒径对纳米铜颗粒制备的影响。在溶液pH值为3、5和7时,可制得铜颗粒,并且在pH=7时制得的铜颗粒粒径最小。在溶液pH为9和11时无法制得铜颗粒。Cu2O的平均粒径能影响铜粉的粒径。Cu2O的平均粒径越大,得到的铜颗粒越大。通过对反应过程中不同时间点收集的样品进行XRD分析,可探索出反应的进程。在反应过程中,Cu(OH)2首先作为前驱体出现,然后被还原为Cu2O,最后被还原为铜颗粒。     

Synthesis of Cr-Al2O3 Cermet Selective Surfaces Coated by SnO2 Thin Film by Air Plasma Spraying

High efficient Cr-Al2O3 cermet selective surfaces coated by sol-gel SnO2 thin film for high-temperature application were synthesized by air plasma spraying(APS),followed further heat and polish treatment.The phase composition and micro morphology of coating samples were characterized by X-ray diffractions(XRD),scanning electron microscope(SEM)and roughmeter respectively.The solar absorptance(α)and thermal emittance(ε)were determined by optical spectrum instrument.The results show that Cr-Al2O3 cermet coating has a high absorptivity nearly 0.90.But unfortunately,the emissivity of these coatings is nearly 0.50 because of the big thickness and coarse surface prepared by APS technique.However,once coated SnO2 thin film,the composite coatings exhibit excellent selective absorbing property of α=0.89 and ε=0.12.Thus,SnO2 thin film plays a significant role in decreasing the emissivity of coatings as antireflection layer.And furthermore,the optical performance shows that more metal content and smooth surface are favorable for the selective absorbing property.Moreover,the coatings have excellent bond strength with stainless steel substrate and thermal shock resistance at high temperature.     

Fe3O4@SiO2@mTiO2-Au复合材料的制备及其催化性能研究

以磁性Fe3O4为核,在其表面负载SiO2,并用介孔TiO2 (mTiO2)进行包覆,用3-氨丙基三甲氧基硅烷对其改性,将纳米金颗粒均匀负载在介孔TiO2表面,制备出核壳型纳米Fe3O4@SiO2 @mTiO2 -Au复合材料。用透射电镜(TEM)、振动样品磁强计(VSM)、X射线光电子能谱分析(XPS)和X射线衍射分析(XRD)等对样品进行表征,确认了核壳结构的存在,尺寸约3 nm的纳米金负载在表面。催化活性测试结果表明,该材料对对硝基苯酚在25 min内降解率达83%,对铁氰酸钾在30 min内降解率达84%。     

Cu-17Ni-3Al-X合金在中性盐雾中的腐蚀行为

采用中性盐雾加速试验、扫描电镜、X射线衍射仪、光电子能谱仪等研究了Cu-17Ni-3Al-X合金在中性盐雾中的腐蚀行为。结果表明:在中性盐雾腐蚀过程中,该合金具有良好的耐盐雾腐蚀性能,合金的腐蚀速率随腐蚀时间的延长而迅速降低,腐蚀480 h后平均腐蚀速率仅为0.010 mm/a。这是因为腐蚀后合金表面生成一层致密的Cu2O膜,随着腐蚀的进行,Cu2O膜增厚,同时外层的Cu2O膜被进一步氧化生成疏松的Cu2(OH)3Cl颗粒。合金在中性盐雾中腐蚀后,主要是α(Cu)固溶体被腐蚀,合金中的第二相仍残留在晶界处。     

Cu/Y2O3掺杂MgB2的组织控制及动力学分析

观察并研究了不同Y2O3含量的Cu/Y2O3共掺杂MgB2的体系,样品通过传统的固相烧结法制备。结合扫描电镜和X射线衍射技术的分析发现,只有在5%Y2O3掺杂的样品中获得了层状组织。选择5%Y2O3含量的体系结合热分析曲线对固相反应阶段进行了动力学分析,得出最概然机理函数为Avrami-Erofeev,n=2,表达式为2[-ln(1-α)]1/2。其意义是随机形核和随后的瞬时生长。最后对动力学参数进行了计算,结果表明反应的活化能和指前因子均先趋于稳定后减小。     

溶胶-凝胶法应用于Cu粉抗氧化工艺研究

应用钛酸丁酯水解形成二氧化钛溶胶对铜粉表面进行包覆处理，样品的耐腐蚀性通过在5％硫酸溶液中浸泡，然后测定溶液在760nm处的透光率来表征，据此研究了不同加水量、加酸量以及溶胶用量对包覆处理效果的影响。结果表明，钛酸丁酯与水的摩尔比为1：2，H^＋浓度为0．32mol／L，溶胶用量在4％～6％范围内，包覆样品浸泡4h后溶液的透光率为80％以上，而原始样品为15％。应用SEM、EDS、XPS以及XRD对包覆样品进行表征。XPS结果表明，样品表面主要有C、Ti、Sn、O、Cu等元素，其中Ti、Sn元素分别为四价和二价。对空气中放置60天后的包覆样品以及原始粉体的X射线衍射（XRD）检测表明，原始粉体表面有Cu2O存在，而包覆处理Cu粉的图谱中仅出现Cu的特征峰。     

Cu2O/TiO2/Pt复合薄膜的制备及其性能

为了降解环境污染物,通过磁控溅射的方法在玻璃基底上溅射沉积Cu2O/TiO2/Pt复合薄膜。采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、紫外可见分光光谱仪(UV-vis)和光致发光光谱仪(PL)对复合薄膜的表面形貌和光学性能进行分析。通过可见光下对甲基橙溶液的光催化降解试验研究了薄膜的光催化活性。结果表明:Cu2O/TiO2/Pt复合薄膜共有3层,从下到上依次为Pt层、锐钛矿型TiO2层和Cu2O层。薄膜表面平整致密,由形状规则的球形颗粒组成。Cu2O/TiO2/Pt复合薄膜的光催化活性高于Cu2O/TiO2复合薄膜的和纯TiO2薄膜的光催化活性。光催化活性的提高是由于Pt层的存在进一步抑制了光生电子与空穴的复合,延长了光生载流子的寿命,提高了量子产率,进而有效地改善了薄膜的光催化活性。