低团聚掺锑氧化锡纳米微粉的制备

以SnCl4?5H2O和SbCl3乙醇溶液为原料,用阴离子树脂交换除氯水解法制得无Cl–的掺锑氢氧化锡胶体沉淀。并用乙酸异戊酯作脱水剂。结果表明,用乙酸异戊酯共沸蒸馏干燥法能有效防止粉体的硬团聚,得到了比表面积为284.43m2/g掺锑氢氧化锡微粉。热处理后得到了低硬团聚、电阻率为0.405?·cm的掺锑氧化锡纳米晶体。     

喷雾热解法制备掺氟的氧化锡透明导电膜

采用喷雾热分解的方法,在片状日用玻璃基材和石英玻璃基材上制得了掺氟氧化锡透明导电薄膜。研究了F 的掺杂量、成膜温度和沉积时间对薄膜方阻 R□和在可见光范围内的平均透过率 T 的影响。实验结果表明,当 NH4F的掺杂量为 SnCl_4·5H_2O 的 32%(质量分数)、成膜温度为 450℃、沉积时间为 15 s 时,可使所得薄膜的方阻 R_□最低,为 10Ω/□,可见光范围内的平均透过率为 80%。     

无团聚纳米级SnO_2粉末及其气敏元件的制备

用液相沉淀法在结晶五水四氯化锡的水溶液中滴加浓氨水，通过在沉淀时加入高分子有机分散剂，剧烈搅拌，控制反应结束时ｐＨ值，用无水乙醇洗涤、冷冻干燥及选取适当的煅烧温度等一系列工艺手段来制取ＳｎＯ２粉末。将得到的粉末用ＴＥＭ、ＢＥＴ及ＸＲＤ半峰宽法测定其粒径大小，证明粉末最小平均粒径可至３．７９ｎｍ且无团聚存在，ＸＲＤ分析表明所得的ＳｎＯ２为四方相。将此粉末制成气敏元件，经测试表明气敏性能有很大提高。     

纳米氧化锡制备方法的研究进展

从制备氧化锡的方法,原理和工艺特点等几方面综述了近年来纳米氧化锡粉末、薄膜、棒、线、带的最新研究进展。着重阐述了制备准一维纳米氧化锡的过程及各自的生长机制。并对纳米氧化锡粉体制备的研究方向和产业化发展趋势作了展望。     

钛基多孔氧化锡纳米结构的制备

研究了采用电沉积和阳极氧化方法在钛基上制备多孔氧化锡纳米结构的技术.在3mm厚的钛片上,采用电沉积的方法首先预沉积镍层,然后沉积1μm厚高纯度锡膜作为阳极浸入0.5mol/L草酸溶液中,在直流恒压5V条件下,进行电化学氧化5min.电化学氧化处理后,分别采用扫描电镜和X射线衍射仪对样品进行了平面、横断面形貌观察和氧化产物分析.结果表明,在钛基上形成了一层厚约1μm、孔径70nm、孔间距80nm的多孔氧化亚锡薄膜,这种多孔结构薄膜可以进一步在空气中加热500℃处理2h,制成钛基氧化锡多孔材料,它也可作为制备钛基纳米复合材料的模板.     

钛基多孔氧化锡纳米结构的制备

研究了采用电沉积和阳极氧化方法在钛基上制备多孔氧化锡纳米结构的技术.在3mm厚的钛片上,采用电沉积的方法首先预沉积镍层,然后沉积1μm厚高纯度锡膜作为阳极浸入0.5mol/L草酸溶液中,在直流恒压5V条件下,进行电化学氧化5min.电化学氧化处理后,分别采用扫描电镜和X射线衍射仪对样品进行了平面、横断面形貌观察和氧化产物分析.结果表明,在钛基上形成了一层厚约1μm、孔径70nm、孔间距80nm的多孔氧化亚锡薄膜,这种多孔结构薄膜可以进一步在空气中加热500℃处理2h,制成钛基氧化锡多孔材料,它也可作为制备钛基纳米复合材料的模板.     

纳米AIN粉末的制备与烧结

利用低温燃烧合成前驱物制备出平均粒度为100 nm的AlN陶瓷粉末,比较了该粉末的常压烧结和放电等离子烧结的特性。实验表明:以合成的AlN粉末为原料,添加5%(质量比)Y2O3作为烧结助剂,在常压、流动N2气氛下1600℃保温3 h,制备出平均晶粒尺寸为4~8μm、密度为3.28 g.cm-3的AlN陶瓷;将同样的粉末不加任何烧结助剂,采用SPS技术在1600℃保温4 min,得到密度为3.26 g.cm-3的AlN陶瓷,晶粒度约为1~2μm。     

有机衬底上掺Sb的SnO2透明导电膜的性质与制备参数关系的研究

采用射频磁控溅射法在透明聚酯胶片上制备出了SnO2∶Sb透明导电膜,主要讨论了制备条件对薄膜光电特性的影响.制备的样品为多晶薄膜,并且保持了二氧化锡的金红石结构,具有明显的[110]的趋向.通过调节制备参数,制备出了电阻率为3.7×10-3 Ω*cm,平均透过率高于80%的高质量薄膜.     

磷锑共掺SnO_2陶瓷的电阻-温度特性

采用湿化学法制备了磷锑共掺氧化锡Sn1–3xSbxP2xO2+δ(x=0.004,0.010,0.030,0.050)材料。利用XRD、SEM、电阻–温度特性测试系统和交流阻抗技术对所制氧化锡材料的物相组成、微观结构及导电特性进行了研究。结果表明:在x=0.004和0.010时,所制氧化锡材料由纯四方结晶相组成,但在x≥0.030时,材料中出现了微量的P2O5和SnP2O7杂质相;所制氧化锡材料的电阻–温度特性具有负温度系数(NTC)效应,这主要是晶粒效应和晶界效应共同作用的结果;最后利用能带理论对该材料的NTC导电机理进行了分析讨论。     

纳米AlN粉末的制备与烧结

利用低温燃烧合成前驱物制备出平均粒度为100 nm的AlN陶瓷粉末,比较了该粉末的常压烧结和放电等离子烧结的特性.实验表明:以合成的AlN粉末为原料,添加5%(质量比)Y2O3作为烧结助剂,在常压、流动N2气氛下1600℃保温3 h,制备出平均晶粒尺寸为4～8 μm、密度为3.28 g·cm-3的AlN陶瓷;将同样的粉末不加任何烧结助剂,采用SPS技术在1600℃保温4 min,得到密度为3.26 g·cm-3的AlN陶瓷,晶粒度约为1～2μm.     

纳米SnO_2粉体的制备与掺杂研究

利用液相沉淀法制备了一系列掺杂型SnO2纳米粉体,晶粒度小于20 nm。研究了Ni2+、Co2+、Cu2+掺杂对SnO2粉体物相结构、晶化行为及晶粒度的影响。分析认为,各SnO2粉体样品都属于金红石结构,掺杂离子以类质同象方式进入SnO2晶格,对SnO2晶胞参数、结晶度、晶粒度等方面产生影响,其中Ni2+和Cu2+的掺入影响较大,可对SnO2晶粒生长有明显的抑制作用,大大降低其晶粒度。     

Properties of fluorine-doped tin oxide films prepared by an improved sol-gel process

Fluorine-doped tin oxide (FTO) films were prepared by an improved sol-gel process, in which FTO films were deposited on glass substrates using evaporation method, with the precursors prepared by the conventional sol-gel method. The coating and sintering processes were combined in the evaporation method, with the advantage of reduced probability of films cracking and simplified preparation process. The effects of F-doping contents and structure of films on properties of films were analyzed. The results showed the performance index (Φ_TC=3.535×10⁻³ Ω⁻¹ cm) of the film was maximum with surface resistance (R_sh) of 14.7 Ω cm⁻¹, average transmittance (T) of 74.4% when F/Sn=14 mol%, the reaction temperature of the sol was 50 °C, and the evaporation temperature was 600 °C in muffle furnace, and the film has densification pyramid morphology and SnO_2−xF_x polycrystalline structure with tetragonal rutile phase. Compared with the commercial FTO films (Φ_TC=3.9×10⁻³ Ω⁻¹ cm, R_sh=27.4 Ω cm⁻¹, T=80%) produced by chemical vapor deposition (CVD) method, the Φ_TC value of FTO films prepared by an improved sol-gel process is close to them, the electrical properties are higher, and the optical properties are lower.     

Substrate temperature effect on the photophysical and microstructural properties of fluorine-doped tin oxide nanoparticles

Transparent conducting oxide of fluorine-doped tin oxide (FTO) thin films was deposited from chemical solutions of tin chloride and ammonium fluoride using streaming process for electroless and electrochemical deposition (SPEED) at substrate temperature 450, 500, and 530 ℃ respectively. The effect of substrate temperatures on the microstructural properties such as crystallite size, dislocation density, micro strain, volume of the unit cell, volume of the nanoparticles, number of the unit cell, bond length and the lattice constants were examined using XRD technique. Only reflections from (110) and (200) planes of tetragonal SnO₂ crystal structure were obvious. The peaks are relatively weak indicating that the deposited materials constitute grains in the nano dimension. Hall measurements, which were done using van der Pauw technique, showed that the FTO films are n-type semiconductors. The most favorable electrical values were achieved for the film grown at 530 ℃ with low resistivity of 7.64×10^-4Ω·cm and Hall mobility of -9.92 cm²/(V·s).     

Electrical and optical properties of deep ultraviolet transparent conductive Ga2O3/ITO films by magnetron sputtering

Ga2O3/ITO films were prepared by magnetron sputtering on quartz glass substrates. The transmittance and sheet resistance of ITO films and Ga2O3/ITO films were measured by using a double beam spectrophotometer and four point probes. The effect of the ITO layer and Ga2O3 layer thickness on the electrical and optical properties of Ga2O3/ITO bi-layer films were investigated in detail. Ga2O3 (50 nm)/ITO (23 nm) films exhibited a low sheet resistance of 323 Ω/□ and high deep ultraviolet transmittance of 77.6% at a wavelength of 280 nm. The ITO layer controls the ultraviolet transmittance and sheet resistance of Ga2O3/ITO films. The Ga2O3 layer thickness has a marked effect on the transmission spectral shape of Ga2O3/ITO films in the violet spectral region.     

Versatile hole injection of VO2: Energy level alignment at N,N′-di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine/VO2/fluorine-doped tin oxide

Energy level alignments at the interface of N,N′-di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine (NPB)/VO₂/fluorine-doped tin oxide (FTO) were studied by photoemission spectroscopy. The overall hole injection barrier between FTO and NPB was reduced from 1.38 to 0.59 eV with the insertion of a VO₂ hole injection layer. This could allow direct hole injection from FTO to NPB through a shallow valence band of VO₂. Surprisingly, VO₂ can also act as a charge generation layer due to its small band gap of 0.80 eV. That is, its conduction band is quite close to the Fermi level, and thus electrons can be extracted from the highest occupied molecular orbital (HOMO) of NPB, which is equivalent to hole injection into the NPB HOMO.     

电纺SnO2纳米纤维的制备及其气敏特性

采用聚乙烯醇（PVA，Mw=80000g/mol）和五水合四氯化锡（SnCl4.5H2O）作为静电纺丝前驱液，着重研究了纺丝电压、前驱液中PVA浓度及煅烧温度等因素对纺丝过程及纤维特性的影响，并用扫描电镜（SEM）和X射线衍射（XRD）等分析手段对纤维的微观结构、表面形貌和结晶状态进行了表征。结果表明，当纺丝电压为4kV、纺丝液中PVA质量分数为7%、退火温度为700℃时，可以得到平均直径为300nm的连续SnO2纳米纤维。该纤维对乙醇的响应恢复时间小于15s，检测极限低于10×10^-9。     

磁控溅射制备Ga2O3/ITO深紫外透明导电膜的光电性能

采用磁控溅射方法在石英玻璃基底上制备了Ga2O3/ITO膜,用紫外-可见分光光度计、四探针测试仪对ITO膜和 Ga2O3/ITO膜的光学透过率和面电阻进行了表征,详细研究了ITO层和Ga2O3层的厚度对Ga2O3/ITO双层膜光电性能的影响。研究表明,Ga2O3(50nm) /ITO(23nm)膜在280nm处的深紫外光学透过率高达77.6%,面电阻为323Ω/sq;ITO层控制Ga2O3/ITO膜的面电阻,影响Ga2O3/ITO膜的紫外透过率;Ga2O3层厚度调控Ga2O3/ITO膜的紫外区域的光谱形状。     

(Cd,Co,Nb)掺杂的SnO2压敏材料的电学性质

研究了Cd对(Co，Nb)掺杂SnO2压敏材料电学性质的影响。组分为97．65％SnO2 O．75％Co2O3 0．10％Nb2O5 1．50％CdO的压敏电阻具有最大非线性系数(a=22．2)和最高的势垒(ψB=0．761eV)．当CdO的摩尔分数从0增加到3％时，(Co，Nb)掺杂SnO2压敏电阻的击穿电压从366V／mm增大到556V／mm，1kHz时的相对介电常数从1429减小到1108。晶界势垒高度测量揭示，SnO2的晶粒尺寸的减小是击穿电压增高和介电常数减小的主要原因。对Cd掺杂量增加引起SnO2晶粒减小的根源进行了解释。     

聚酰亚胺衬底掺Sb的SnO_2透明导电膜的制备

用射频磁控溅射法在聚酰亚胺衬底上制备出了相对透过率为80%左右、最小电阻率为3.710-3 W·cm、附着良好的SnO2∶Sb透明导电膜。 靶材中Sb2O3的最佳掺杂量为6%(质量分数),最佳溅射压强为1 Pa(90%Ar+10%O2)。制备的样品为多晶薄膜,并且保持了二氧化锡的金红石结构,具有明显的[110]的趋向。并讨论了薄膜的结构和光电特性随衬底温度的变化。     

Using Ⅰ-Ⅴ characteristics to investigate selected contacts for SnO2:F thin films

Fluorine doped tin oxide (SnO2:F) thin films were prepared on glass substrates by the spray pyrolysis (SP) technique at different substrate temperatures between 380-480 ℃.The microstructure of the film...