交流电在Al2O3模板中沉积金属机理探讨

以铝阳极氧化形成有序的多孔氧化铝为模板,利用交流电在模板孔洞中沉积金属Ag得到纳米Ag粒子/Al2O3组装体系,透射电镜观察证实在氧化铝模板中有金属纳米Ag粒子存在.分析了交流电能在孔洞中沉积金属的原因是由于Al/Al2O3界面的整流特性,测量了Al/Al2O3界面的I－U关系曲线.     

交流电在Al_2O_3模板中沉积金属机理探讨

以铝阳极氧化形成有序的多孔氧化铝为模板,利用交流电在模板孔洞中沉积金属Ag得到纳米Ag粒子/Al2O3组装体系,透射电镜观察证实在氧化铝模板中有金属纳米Ag粒子存在.分析了交流电能在孔洞中沉积金属的原因是由于Al/Al2O3界面的整流特性,测量了Al/Al2O3界面的I－U关系曲线.     

发光材料用纳米Al2O3的研究

研究了异丙醇铝在不同的溶剂相中进行水解反应制备纳米Al2O3的前驱体AlOOH，以聚乙烯醇作为模板剂和热处理条件下，前驱体转相为纳米Al2O3，并自组装成球形纳米Al2O3聚集体，TEM和SEM观察结果表明，纳米Al2O3粒径为20nm左右，球形聚集体从100nm至3um。     

颗粒模板法制备大孔Al2O3材料

采用颗粒模板法制备了大孔氧化铝(Al2O3)材料. 扫描电子显微镜(SEM)结果显示, 大孔Al2O3结构中的大孔呈“囊泡状”且孔道的贯通性较差. Zeta电位测量表明, 共沉积条件下聚苯乙烯(PS)和Al2O3两种胶体颗粒带有相反的电荷, 在静电引力作用下先发生了吸附, 再沉积在一起. 吸附在PS微球表面的Al2O3纳米颗粒形成的吸附层是导致大孔呈“囊泡状”和孔道不贯通的主要原因. 采用聚二烯丙基二甲基氯化铵(PD)溶液对PS胶体微球带电性质进行了改性, PS微球的Zeta电位由−44.36 mV变成了+37.41 mV, 进而消除了沉积过程中二元颗粒间的吸附现象. 扫描电子显微镜显示, 大孔样品中“囊泡状”大孔消失, 同时孔道贯通性得到改善.     

锂离子电池用α-Fe2O3-Ag复合纳米棒负极材料的制备及储锂性能

采用FeOOH纳米棒为前驱体,通过层层自组装法及随后的热处理过程制备出α-Fe2O3-Ag复合纳米棒.采用透射电子显微镜(TEM)、高分辨透射电子显微镜(HRTEM)和电化学性能测试对样品的形貌、结构及电化学性能进行了表征.结果表明,Ag纳米颗粒均匀地分布在α-Fe2O3纳米棒的表面.作为锂离子电池负极材料,α-Fe2O3-Ag复合纳米棒表现出了较好的循环性能和较高的比容量.180个循环后,其比容量高达549.8 mA.h/g.     

以CuC2O4微球为模板可控合成一维CuC2O4/ZnO异质结构

以CuC2O4纳米微球为模板,通过水热法在120 ℃、1 h时成功合成了一维CuC2O4/ZnO异质结构。 采用热重分析（TGA）、场发射扫描电子显微镜（FE-SEM）、能量散射Ｘ射线谱（EDX）、透射电子显微镜(TEM)和Ｘ射线粉末衍射(XRD)等测试技术对产物的结构和形貌进行了表征。 结果表明,所得产物为一维CuC2O4/ZnO纳米棒束,长约1 μｍ,直径约500 nm。 每个棒束由许多纳米棒沿同一方向组装而成。 TEM照片和EDX光谱表明,CuC2O4和ZnO形成了均匀的异质结构。     

球形和花形ZnO纳米结构的可控制备及其光催化机理

报道了一种简单的制备球形和花形ZnO纳米结构的无模板水热法。在Zn(NO_3)_2·6H_2O与NH_3·H_2O的体系中,通过改变乙二醇和水的体积比,140℃水热反应2 h分别制备出球形和花形ZnO纳米结构。采用SEM、XRD、UV-Vis DRS和PL对其进行了表征和分析,结果表明球形ZnO纳米结构的直径为500 nm~1μm,它是由纳米颗粒自组装而成;花形ZnO纳米结构是由长度为300~700 nm,直径为100~300 nm的纳米棒组装而成。研究了乙二醇在球形和花形ZnO纳米结构形成过程中的作用并提出了可能的生长机理。室温下分别以球形和花形ZnO纳米结构为光催化剂,以偶氮染料甲基橙MO作为光催化研究对象,紫外光照2 h,对MO的降解率分别为83%和55%。以叔丁醇(t-Butanol)、乙二胺四乙酸二钠(EDTA-2Na)为自由基和空穴的捕获剂,推测其催化机理主要为空穴氧化和自由基协同氧化历程。     

超临界抗溶剂法制备纳米氧化铝颗粒

以CO2为抗溶剂介质,无水乙醇为溶剂,采用超临界抗溶剂法制备了Al2O3前驱体硝酸铝纳米颗粒,考察了温度和溶液浓度等因素对制备过程的影响,并通过焙烧前驱体硝酸铝制得了纳米Al2O3球形颗粒.采用热重-质谱、X射线衍射、透射电镜和场发射透射电镜对所制备的硝酸铝和Al2O3纳米颗粒进行了表征,并用H2程序升温还原技术初步考察了纳米Al2O3负载Ni催化剂的还原性能,发现纳米Al2O3比一般Al2O3载体对活性组分Ni具有更好的分散性能.     

水热法制备ZnO二维周期有序孔结构薄膜

在由溶胶-凝胶法制备的纳米ZnO薄膜衬底上,以Zn(NO3)2.6H2O和六亚甲基四胺(HMT)等摩尔浓度配制成前驱体溶液,在单层聚苯乙烯(PS)微球模板辅助下,采用水热法制备了具有规则多孔结构的ZnO薄膜。探讨了PS微球作为模板对ZnO纳米棒生长的限制作用以及柠檬酸钠在水热制备方法中对晶体生长的影响。利用扫描电子显微镜(SEM)和X射线衍射(XRD)表征了水热反应后所得二维有序ZnO膜表面形貌和取向性,测量了ZnO薄膜的光致发光(PL)光谱并研究其相应机理。     

ZnO纳米管有序阵列与Cu_2O纳米晶核壳结构的光电化学性能及全固态纳米结构太阳电池研究

采用电化学方法在铟锡氧化物(ITO)导电玻璃基底上制备了高度有序的ZnO纳米管阵列,然后在ZnO纳米管阵列上电化学沉积Cu2O纳米晶颗粒,获得了一维有序Cu2O/ZnO核壳式纳米阵列结构,通过控制Cu2O纳米晶的沉积电量得到不同厚度的Cu2O壳层,并对该核壳式纳米阵列的形貌和结构进行了分析.以Cu2O/ZnO一维核壳式纳米阵列结构为光电极组装全固态纳米结构太阳电池,研究了Cu2O壳层厚度对光电极光吸收性能、光电性能以及组装电池光伏性能的影响,优化了电池中对电极材料的喷金厚度.结果表明,以Cu2O沉积电量为1.5 C的Cu2O/ZnO为光活性层,以4 mA电流下真空镀金20~25 min的铜基底为对电极组装的简易太阳电池最高可获得0.013%的光电转换效率.     

Co、Ni及其合金纳米线阵列的制备及磁性研究

采用交流电化学沉积法,在多孔阳极氧化铝(AAO）模板孔洞中成功组装了铁磁性金属Co、Ni、CoNi合金纳米线阵列并采用扫描电子显微镜(SEM）、X射线衍射(XRD）等对样品进行表征。结果表明,Co、Ni及CoNi合金阵列体系中纳米线均匀有序,形状各向异性较大(长径比达30以上）,有显著的结晶择优取向。对Co、Ni、CoNi合金纳米线阵列体系进行磁性分析,振动样品磁强计(VSM）测试结果显示,纳米线有明显的磁各向异性,适合用作垂直磁记录介质。纳米线阵列退火后沿纳米线方向矫顽力和矩形比减小,样品的垂直磁各向异     

ZnO纳米线阵列的电沉积法制备及表征(英文)

利用直流电沉积方法在多孔氧化铝模板的孔洞中生成锌纳米线,在氧气氛围中,于800°C下氧化2h,将氧化铝中的锌氧化成氧化锌.本研究利用氧气氛围进行锌的氧化,大大提高了传统方法的氧化锌纳米线的制备效率.用场发射扫描电子显微镜(FE-SEM)、透射电子显微镜(TEM)和X射线衍射仪(XRD)对其形貌及成分进行表征和分析,结果表明,氧化铝模板的有序孔洞中填充了大尺寸、均匀连续的多晶态氧化锌纳米线.纳米线具有约1000:1的高纵横比,其长度等于氧化铝模板的厚度,直径约为80nm.光致发光(PL)光谱表明,氧化锌纳米线在504nm处有由于氧空位引起的较强蓝绿光发射.这为进一步研究ZnO/AAO组装体发学性质和开发新型功能器件提供了基础.     

Synthesis and characterization of fluorescent N-CDs/ZnONPs nanocomposite for latent fingerprint detection by using powder brushing method

This study reports the first new approach of using nitrogen functionalized carbon dots coated on zinc oxide nanoparticles (N-CDs/ZnONPs) as a novel nanocomposite for latent fingerprint detection using the powder brushing method. N-CDs/ZnONPs nanocomposite was prepared using melamine, potato peel waste and zinc acetate dehydrate as precursors. This nanocomposite was characterized by Fourier-transform infrared spectroscopy, UV–Visible spectroscopy, Fluorescence spectroscopy, X-ray diffraction, Raman spectroscopy, Zeta nanosizer, Scanning Electron Microscope, Energy-Dispersive X-ray Spectrometry and Transmission Electron Microscopy. The size of N-CDs was around at 50–20 nm and ZnONPs was around at 40–50 nm. The quantum yield of N-CDs increased the fluorescence intensity of the fluorophore by 5.54%. The N-CDs were coated on surface of ZnONPs to increase the quantum yield and increase the blue emission after formation of N-CDs/ZnONPs by 5.12%.The N-CDs/ZnONPs nanocomposite demonstrated extraordinary sensitivity and selectivity for Latent Fingerprint (LPF) detection on the distinctive non-porous substrates which included aluminum foil, aluminum sheets, an aluminum rod, an iron disc, a compact disc, a black mat, white marble and magazine paper. This nanocomposite acts as a labeling agent and it helped to detect LFP with clear readability ridges and high contrast fingerprint images under UV light irradiation. N-CDs/ZnONPs nanocomposite additionally demonstrated superior ability to reveal readability ridges and clarity and high contrast LFP images with 415 nm and 450 nm light sources and a yellow filter by using a Living Image Microscope. This nanocomposite exhibited advantages such as improved efficiency, a non-toxic nature, good optical properties and good results in the LFP detection of the freshly applied fingerprints. N-CDs/ZnONPs nanocomposite is, therefore, a good alternative material for detection of latent fingerprints in crime investigations.     

Preparation and optical properties of ThO(2) and Eu-doped ThO(2) nanotubes by the sol-gel method combined with porous anodic aluminum oxide template

In this paper, we report the synthesis of thorium oxide and Eu-doped thorium oxide nanotubes for the first time using the sol-gel method in porous anodic aluminum oxide template. Transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were applied to characterize the morphology and structure of the as-prepared nanotubes. It has been demonstrated that Eu(3+) ions were homogeneously doped into the ThO(2) crystal lattice. The optical properties resulting from Eu-doped products were investigated by means of photoluminescence spectroscopy. Strong visible light emissions were observed at low doping concentration, and the luminescent intensity decreased at high doping concentration. The luminescent centers were concluded to be the Eu(3+) ions in the cubic (O(h)) sites rather than the C(3v) sites, which accounted well for the decrease of luminescent intensity at high doping concentration.     

有序CdS纳米线阵列的制备和光学特性

应用直流电沉积法在多孔氧化铝模板中制备了高度有序的CdS纳米线阵列,并由XRD、Raman、SEM、TEM和HRTEM等进行物理化学表征.结果表明,沉积在多孔氧化铝模板中的CdS呈六角结构,c轴沿孔长度方向定向生长.紫外吸收光谱研究表明,随着纳米线尺寸的减小,纳米线阵列的吸收边向短波长方向移动,荧光光谱测量显示,CdS纳米线阵列的荧光强度高于氧化铝模板,而且在可见光区的荧光特性与激发波长无关.     

Double template electrochemical deposition and characterization of NiCo and NiCu alloys nanoparticles and nanofilms

The principle of double template deposition technique was developed to prepare NiCo and NiCu alloy nanomaterials. Ordered particles of about 800 nm high were obtained by reduction of ions from aqueous solution into the pores of anodic aluminum oxide (AAO) membrane with intact barrier layer. The size of the nanoparticles was significantly reduced by combination of AAO and the hexagonal phase of a lyotropic liquid crystal. The scanning tunneling microscopy (STM) micrograph of the material prepared in the presence of liquid crystal reveals the hexagonal array of cylindrical pores. The corrosion potential of the alloy nanofilm shifted to more negative values when the sizes of the particles decrease. The anodic linear sweep voltammetry shows, in each case, various current peaks characteristic of the dissolution of chemical elements in the film.     

Pd/CZ三效催化剂中钯的团聚现象研究

通过浸渍法制备了一系列负载0.5%（重量百分比）Pd的氧化铈-氧化锆（NDK-84,由日本新日本电工株式会社提供）催化剂材料,并通过全面的表征手段,包括扫描电子显微镜（SEM）、透射电子显微镜（TEM）、高分辨透射电子显微镜（HR-TEM）、元素分布、X-射线衍射（XRD）,氮气吸脱附测试与比表面积和孔径分布分析（BET）、X射线光电子能谱（XPS）等,研究了不同Pd前驱体和不同热老化处理条件、H₂还原条件对Pd在铈锆固溶体上的分散、生长与烧结行为的影响,并评估了它们的三效催化活性.结果表明,热老化处理过程与还原过程显著影响了Pd在氧化物载体表面上的分散,因此导致不同的催化活性.     

基于超氧化物歧化酶/氧化锌的超氧离子传感器

利用物理气相沉积法制备了纳米氧化锌(Nano-ZnO) 膜, 通过扫描电子显微镜(SEM)、紫外-可见分光光度法(UV-Vis)、X 射线衍射(XRD)及电化学等方法测定了其物理化学性质. 实验结果表明, 该Nano-ZnO 膜是具有多晶六边形纤维锌矿结构的多孔纳米膜, 微粒直径在 50～100 nm, 室温禁带宽度3.37 eV. 采用浸渍法将超氧化物歧化酶(SOD)直接修饰于 Nano-ZnO 膜上, 制备了SOD 修饰电极(SOD/ZnO). 通过交流阻抗法(EIS)及循环伏安法(CV)证明了SOD能稳定地吸附在多孔ZnO膜上, 并实现了直接电子传递; 紫外-可见及红外光谱研究证明吸附在ZnO膜上的蛋白质保持了良好的生物催化活性, 并成功地构建了第三代超氧离子(O2-)生物传感器. 这种生物传感器有较宽的线性范围(氧化电流: 0.24~180×10-6 mol/L, 还原电流: 0.12~250×10-6 mol/L)、较低的检测限(氧化电流: 2×10-7 mol/L, 还原电流: 1×10-7 mol/L)、较快的响应时间(4 s)以及较好的稳定性.     

Selective dissolution of the silver component in colloidal Au and Ag multilayers: a facile way to prepare nanoporous gold film materials

Colloidal Au/Ag multilayer films were prepared by alternate assembly of Au nanoparticles with a size of 5 +/- 1.2 nm and Ag nanoparticles with a size of 10 +/- 2.4 nm by using 1,5-pentanedithiol as cross-linker. Nanoporous gold films with a ligament size of 26.7 +/- 4.6 nm were then prepared by selective dissolution of sacrificial templates of silver particles in colloidal Au/Ag multilayers. The complete dissolution of Ag particles in colloidal Au/Ag multilayers in a mixture solution of 3.0 mM HAuCl(4) and 3 M NaCl took place at room temperature without damage of the colloidal Au film. This method to prepare nanoporous gold films was further extended to the preparation of nanoporous gold nanotubes by depositing colloidal Au/Ag film on the inner wall of anodic aluminum oxides (AAO) followed by dissolution of colloidal Ag and removal of AAO templates.     

Nature of paramagnetic centers in anodic aluminum oxide formed in a solution of tartaric acid

Films of anodic aluminum oxide, prepared in an aqueous solution of 0.4 M tartaric acid, are studied by means of electron paramagnetic resonance (EPR) before and after heating at 200–700°C. The presence of a carbon radical is established in the films (g factor, 2.0027 ± 0.0002). The nature and conditions of its formation during the electrochemical oxidation of aluminum and the heat-treating of anodic aluminum oxide films are discussed.