钕掺杂ZnO薄膜的制备及抗凝血性能研究

采用射频磁控溅射方法在硅(100)衬底上制备了不同含量元素钕(Nd)掺杂的氧化锌薄膜.XRD分析表明,所有ZnO薄膜都具有c轴择优取向.随着Nd掺杂量的增加,(002)衍射峰的强度减弱,颗粒的尺寸变小.紫外-可见光谱分析表明,所有薄膜在可见光区的透过率超过85%,随着Nd掺杂量的增加,光学带隙从3.30 eV增加到3.40 eV.用XPS对薄膜的表面化学态进行表征,Nd元素在ZnO薄膜表面以Nd3+离子态存在.用接触角测试薄膜表面的浸润性,并计算其表面能.用血小板粘附实验研究不同含量Nd掺杂ZnO薄膜的血液相容性,其结果表明稀土钕掺杂后血小板的粘附数量和形变都较少,稀土掺杂和疏水性的提高是改善氧化锌薄膜抗凝血性能的主要原因.     

真空烧结Nd:YAG透明陶瓷的研究

以高纯Al2O3、Y2O3和Nd2O3粉体为原料,少量MgO和SiO2为添加剂,采用真空烧结方法制备了不同掺杂浓度的NdYAG(Y3Al5O12)透明陶瓷,并且对烧成的NdYAG陶瓷的显微结构和光学性能进行了研究.结果发现,真空烧结有利于气孔的排出,从而达到几乎完全致密化;适量烧结助剂的添加,有利于提高陶瓷的烧结活性和透光性;NdYAG陶瓷能够实现高浓度掺杂,但是透过率随着Nd掺杂量的增加有所降低,光吸收随着掺杂量的增加而增加;掺杂浓度升高,发射谱峰出现展宽,并且出现红移现象,当Nd3+的掺杂浓度大于3.0%(原子分数)时,发射强度急剧降低.     

Eu、Nd、Y稀土掺杂CuAlO_2纳米粉末制备及相组织研究

采用柠檬酸络合的无机盐溶胶-凝胶法制备稀土掺杂铜铁矿结构的CuAlO2粉末,掺杂元素M为稀土Eu、Nd、Y。用DSC-TGA、X射线衍射仪、紫外-可见光分光光度计等测试方法分别对掺杂CuAl1-x MxO2粉末的形成过程、物相结构、光学性能等进行研究。结果表明,稀土掺杂前驱体粉末经950℃煅烧后形成CuAlO2相;经1 100℃保温4h的煅烧后,粉末相组成取决于稀土掺杂量,当稀土元素M(Eu、Nd和Y)的掺杂量为0.5%时,试样由CuAlO2主相和少量CuO杂相组成,当掺杂量≥1%时,由CuAlO2主相、少量CuO和MAlO3杂相组成,YAlO3杂相峰强度较低。提高煅烧温度有利于掺杂元素的溶入,生成CuAl1-xMxO2纯相,但提高到1 150℃时CuAlO2分解;Eu掺杂量1%时,掺杂样品光学带隙增大,电阻率减小,光电性能得到改善。     

Sn掺杂CdO透明导电薄膜的制备和光电性能研究

通过脉冲激光法在石英玻璃基底上沉积了锡掺杂氧化镉(Sn-CdO)透明导电薄膜.X射线衍射,分光光度计和霍尔效应仪检测了薄膜的结构、光学和电学性能.结果表明Sn的掺杂提高了薄膜[111]方向的择优生长,而且促使了(200)晶面衍射角增大.Sn-CdO薄膜的光学禁带宽度随着Sn掺杂含量的增加而变宽.另外,适量的Sn掺杂可以明显改善CdO薄膜的电学性能,比如2.9 at％ Sn掺杂CdO薄膜的电阻率是未掺杂薄膜的十二分之一,载流子浓度是未掺杂的十三倍.因而光学和电学性能的改良使得Sn-CdO薄膜作为透明导电材料具有重要的应用价值.     

ZnS:Mn荧光粉的溶剂热法制备及其发光性能

采用溶剂热法合成了ZnS∶Mn荧光粉,讨论了锰掺杂量对硫化锌发光性能的影响。通过扫描电镜(SEM)、X射线粉末衍射仪(XRD)、紫外可见分光光度计(UV-Vis)和荧光分光光度计(PL)对合成的ZnS∶Mn荧光粉的结构和光学性能进行了表征。结果表明:ZnS∶Mn荧光粉的平均粒径为13.5nm,在波长340nm~200nm处有强吸收,Mn离子浓度在所研究范围内,锰掺杂量对硫化锌的晶型、结晶度、粒径无影响,但对其能级结构影响显著,且随着Mn离子掺杂量的增加,发光强度先增加后减小,掺杂量为5%时达到最大值。     

磁控溅射Zr掺杂ITO薄膜在3种模拟腐蚀环境中的电学稳定性和耐腐蚀性

过去,鲜有Zr掺杂氧化铟锡（ITO）薄膜电学稳定性及耐蚀性的研究报道。采用磁控溅射法制备了ITO薄膜和Zr掺杂ITO薄膜（ITO：Zr）,研究了2种薄膜的微观结构、光电性能及其在3种模拟腐蚀环境（酸性、海洋、工业）腐蚀液中的电学稳定性及耐腐蚀性。结果表明：Zr的掺杂导致了ITO薄膜择优取向向（400）晶面转变,ITO：Zr薄膜比ITO薄膜具有更好的光电性能;2种薄膜在3种环境介质中都能发生自钝化,在工业环境中具有最好的耐腐蚀性能;ITO：Zr薄膜比ITO薄膜具有更好的电学稳定性和耐腐蚀性。     

衬底温度对ITO和ITO:Zr薄膜性能的影响

利用双靶共溅法在玻璃衬底上沉积了Zr掺杂ITO薄膜,对比研究了在不同衬底温度下ITO和ITOZr薄膜性能的变化.XRD和AFM分析表明,ITOZr比ITO薄膜具有更好的晶化程度和较低的表面粗糙度,Zr的掺入促进薄膜晶化的同时导致了(222)晶面向(400)晶面取向的转变.室温下Zr的掺杂显著改善了薄膜的光电性能,方阻由260.12 Ω降为91.65Ω,光学透过率也有所上升.随着温度的上升,方阻可达到10 Ω,薄膜也表现出明显的"B-M"效应,通过直接跃迁的模型得出ITOZr比ITO薄膜具有更宽的光学禁带.共溅法制备的ITOZr薄膜比传统的ITO薄膜展现了更好的综合性能.     

ZrO2掺杂BaCo0.7Fe0.2Nb0.1O3-δ材料的高温结构稳定性和电学性能

为了制备ZrO2掺杂的BaCo0.7Fe0.2Nb0.1O3-δ(BCFN)样品并研究其高温化学稳定性和电学性能,分别通过XRD研究了材料相成分的变化;通过收缩率和密度的测量并结合SEM研究了材料的微观结构;通过TG实验研究了材料在一定气氛下随温度的失重变化;通过直流四电极法测量了材料总电导的变化规律.研究结果表明,BCFN掺杂ZrO2之后材料为双相复合结构.随着ZrO2掺杂量的增加,材料在惰性气氛和氢气气氛下表现出更好的结构稳定性.ZrO2掺杂与未掺杂的BCFN体系其电学性能随温度的变化规律相同,在570℃之前的低温范围以P型半导体电子空穴导电机制为主,在高温则是同时存在电子空穴导电与氧离子导电,随着ZrO2掺杂量的增加,材料在空气气氛下的总电导率依次下降.     

分散剂对铟锡氧化物(ITO)粉末粒径的影响

以纯In、SnCl4·5H2O和盐酸为原料,氨水为沉淀剂,采用络盐法制备了纳米铟锡氧化物(ITO)粉末。主要研究了分散剂对ITO纳米粉体粒径的影响。用激光粒度仪、XRD、SEM对所得粉末进行表征。结果表明:随着分散剂的分子量的增加,所得ITO的粒径逐渐变小;加入不同分子量的PEG配合使用有利于制备纳米级颗粒,加入PEG(10000∶6000=1∶1)作分散剂所制ITO粉末粒径为50～100nm。     

磁控溅射Al掺杂ZnO薄膜结构及光电性能研究

采用磁控溅射法在石英玻璃衬底上制备不同铝(Al)掺杂量的铝掺氧化锌(AZO)薄膜。利用X射线衍射仪、原子力显微镜、四探针测试仪和透射光谱仪等手段研究了不同Al掺杂量对AZO薄膜结构、形貌、电学和光学性能的影响。结果表明,所有样品均为ZnO六方纤锌矿晶体结构,具有较好的c轴择优取向;随着Al掺杂量的增加,薄膜结晶稍有变差,电阻率逐渐降低,透过率逐渐增加。当Al掺含量为3%(vol,体积分数)时,AZO薄膜的综合性能更好,电阻率约3.52×10~(-3)Ω·cm,平均透光率可达到80%,光学禁带宽度达到3.23eV。     

Ag-Nd2O3复合介质薄膜的光吸收特性研究

在真空中用蒸发沉积的方法制备了埋藏有金属Ag纳米微粒的稀土氧化物复合介质薄膜Ag-Nd2O3.通过对这种薄膜的透射电子显微镜观察和光吸收实验研究,发现在相同Nd2O3的薄膜上沉积数量和大小不同的Ag纳米粒子,Ag-Nd2O3复合介质薄膜的光吸收特性随Ag粒子尺寸和体积分数的增大,吸收峰向长波方向移动.而且在光波长310～1 200 nm区域内,吸收比随Ag粒子尺寸和体积分数的增加而增加.分析表明Nd2O3与Ag粒子之间的相互作用是影响吸收峰位置和吸收比大小的主要原因,Ag粒子的体积分数是导致吸收峰移动的主要因素.     

TiO2 nanoparticles co-doped with silver and nitrogen for antibacterial application

We have prepared a series of TiO2 nanoparticles for antibacterial applications. These TiO2 nanoparticles were prepared by the hydrolysis precipitation method with Ti(OBu)4, silver nitrate and ammonia. Crystal structure, particle size, interfacial structure and UV-visible light response of the prepared nanoparticles were characterized by X-ray diffraction measurements (XRD), Transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR) and UV-Vis diffuse reflectance spectroscopy (UV-Vis-DRs). The XRD spectra showed that all samples were anatase structure calcined at 450 degrees C for 3 hours. The Ag doping made the peak of diffraction wider. The results of TEM showed that the nanoparticles of TiO2, N-TiO2 and 1% Ag-N-TiO2 were all spherical in shape and well distributed with a mean size of 19.8 nm, 39.2 nm and 20.7 nm, respectively. N doping caused the nanoparticle size to increase, while, when the doped amount of Ag+ increased, the TiO2 particle size decreased. The FTIR revealed that Ag and N doping of TiO2 appeared to have strong absorption by -OH group and showed the characteristic absorption band of NH4+ and Ag. The UV-Vis-DRs indicated that the absorption band of Ag-N co-doped TiO2 had red shift and that the optical absorption response (between 400 nm and 700 nm) had obvious enhancement. The antibacterial properties of nanoparticles were investigated by agar diffusion method toward Escherichia coli and Bacillus subtilis. The results indicated that both Ag- and N-doped TiO2 could increase the antibacterial properties of TiO2 nanoparticles under fluorescent light irradiation. A 1% Ag-N-TiO2 had the highest antibacterial activity with a clear antibacterial circle of 33.0 mm toward Escherichia coli and 22.8 mm toward Bacillus subtilis after cultivation for 24 hours.     

Nd掺杂LaFeO_3纳米粉体的合成及其可见光催化活性

采用柠檬酸络合法于600℃煅烧2h合成了钙钛矿型La1-xNdxFeO3（x=0,0.05,0.10,0.15,0.20,0.25）纳米光催化剂,并利用X射线能谱（EDS）、热重-差热（TG-DTA）、X射线衍射（XRD）、扫描电镜（SEM）以及紫外可见漫反射吸收光谱（UV-VisDRS）等技术进行了表征,以次甲基蓝为目标降解物、以荧光灯模拟可见光源考察了Nd掺杂量对其可见光催化活性的影响.结果表明,Nd已经掺入LaFeO3晶体中,Nd的最佳掺杂量为x=0.1.La0.9Nd0.1-FeO3光催化剂可将次甲基蓝1h降解率由未掺杂的56.0%提高到80.4%,这是由于掺杂后粉体粒径由20.2nm减小到16.9nm,表面原子比例增加以及掺杂后纳米粉体在可见光区的吸收增强所致.     

Characterization of pure and doped zirconia nanoparticles with infrared transmission spectroscopy

Infrared transmission spectroscopic studies of pure and doped zirconia nanoparticles with different average particle sizes have been made with conventional XRD and TEM techniques. Infrared spectra of these pure or doped zirconia samples are well characterized by their unique spectral features or optical phonons. Blue shifts and broadening of the absorption bands are observed with the decrease of particle size. The seeming “disappearances” of band 628 cm ^{− 1} in pure zirconia nanoparticles and band 610 cm ^{− 1} in the doped zirconia nanoparticles are attributed to the overlap of broad absorption bands. Blue shift of the absorption bands are also caused by the doping of Al₂O₃, which exists metastably in the Y-TZP lattice and decreases the interplanar distance. The contributions of the “interface effect” and “fine size effect” to infrared absorption are also discussed.     

Growth of SnO(2) nanocrystals controlled by erbium doping in silica

We investigate the effects of erbium doping on SnO(2) nanoclustering in Sn-doped silica. Vibrational spectroscopy data from Raman and infrared absorption measurements show nanostructuring effects on the SnO(2) nanophase. Ultraviolet absorption spectra evidence a gap shift ascribable to size-dependent quantum confinement, also suggesting a role of erbium doping in determining cluster sizes and the amount of localized states on the nanophase boundary. Transmission electron microscopy confirms and details the spectroscopic data. As a result of these measurements, we find that the nanocrystal size distribution becomes narrower, increasing the erbium concentration, while the density of localized states at the nanocrystal surface decreases. The distribution of erbium ions among the possible environments is then examined through simultaneous spectroscopy of luminescence excited by nanocrystal-to-erbium energy transfer and the absorption of nanocrystal luminescence by erbium ions. This analysis shows that erbium behaves as an extrinsic nucleation centre of the SnO(2) nanophase at low doping levels, whereas at high concentrations it modifies the matrix, hindering the growth of SnO(2) crystals and passivating the interface.     

Effect of Sn doping on the growth and optical properties of AgI nanoparticles

Controlled iodization and Sn doping of vacuum-evaporated Ag films has helped understand the initial-stage kinetics of AgI nanoparticle growth under ambient conditions. Use of XRD, optical spectroscopy, and AFM has unravelled systematic correlation between Sn-induced disorder in Ag crystal structure, nanoparticle size, and exciton growth dynamics. Sn doping of Ag leads to three specific effects: removal of UV absorption minimum in Ag, introduction of a plasmon-type absorption in the red region, and a reduction in particle size in thicker (than 10 nm) films (but an increase in particle size in 10 nm films) relative to that in undoped Ag films.     

Size influence on optical absorption property of ultra-fine nickel hollow spheres

Nickel hollow spheres (NHSs) with different diameter have been synthesized by the autocatalytic reduction method. The morphology, particle size distribution and optical absorption property of NHSs were investigated. The optical absorption intensity obviously increases in ultraviolet—near infrared region with the decrease of particle size. While in infrared region, nickel hollow spheres have almost no absorption. After the heat treatment process, the grain sizes of samples become bigger and the absorptances decrease in UV–Vis–NIR region. For smaller particles, the absorption peak in ultraviolet range moves from 375 to 440 nm because of the increase of grain size after heat treatment.     

尖晶石结构Ni掺杂ZnFe2O4纳米颗粒的性能表征

利用水热法成功合成了纯ZnFe2O4和不同含量Ni掺杂Zn1-xNixFe2O4纳米颗粒。采用X射线衍射(XRD)、高分辨透射电子显微镜(HRTEM)、选区电子衍射(SAED)、X射线能量色散分析(XEDS)、紫外可见吸收光谱(UV-Vis)、傅里叶变换红外光谱(FT-IR)和振动样品磁强计(VSM)等测试技术研究掺杂浓度对Zn1-xNixFe2O4(x=0,0.1,0.3,0.5)样品的晶体结构、形貌、光学性能和磁学性能的影响。结果表明:所制备的Zn1-xNixFe2O4纳米颗粒结晶良好,Ni2+以替代Zn2+的形式掺杂到ZnFe2O4晶格中,生成立方尖晶石结构ZnFe2O4。随着Ni含量的增加,晶粒尺寸增大,晶格常数发生收缩。样品的形貌呈不规则的椭球形,且颗粒大小比较均匀。红外光谱的吸收峰位置并没有随Ni掺杂浓度的增加而变化。Zn1-xNixFe2O4纳米晶的光学带隙随Ni掺杂浓度增加而增大,与相应块体相比发生蓝移。在室温下,纯ZnFe2O4纳米晶呈现超顺磁性,掺杂样品具有明显的铁磁性。     

Chemical,morphological, structural,optical, and magnetic properties of Zn<Subscript>1−x</Subscript>Nd<Subscript>x</Subscript>O nanoparticles

In the present investigation, we made an endeavor to fabricate the ZnO nanoparticles and achieved the tunable properties with Nd doping. The Nd-doped ZnO nanoparticles were characterized via X-ray diffraction (XRD), Raman, and X-ray photoelectron spectroscopy (XPS) studies that confirmed the successful doping of Nd ions in the ZnO crystal lattice without amending its hexagonal phase. The particle morphology revealed nearly spherical particles with uniform size distribution. The band gap of these samples was determined using diffuse-reflectance spectra (DRS) and was found to vary from 3.17 to 3.21 eV with increasing Nd concentration. A broad and intense emission band at 1083 nm for Nd doped ZnO nanoparticles is observed and is assigned to corresponding emission transition ⁴F_3/2?→?⁴I_11/2 of Nd³⁺ ions. Furthermore, the magnetic studies indicate that the Nd doping altered the magnetic behavior of nanocrystalline ZnO particles from diamagnetic to ferromagnetic at 300 K and that the magnetization of these samples decreased with increasing Nd concentration. The tunable optical band gap as well as room-temperature ferromagnetism of these samples may find applications in both optoelectronics and spintronics.     

掺Nd纳米ZnO薄膜特性研究

研究了用真空蒸发法在玻璃衬底上制备稀土掺杂纳米ZnO薄膜结构、导电性及光透射性能。结果显示 ,在 5 0 0℃氧化、热处理稀土元素Nd掺杂后能够明显改善纳米ZnO薄膜的结构特性 ,薄膜的晶粒尺寸随掺杂含量的增加而减小。掺Nd使ZnO薄膜的电性能有所改善但使纳米ZnO薄膜的光透射性有所降低。