氨化Si基Ga2O3/V膜制备GaN纳米线

氨化硅基钒应变层氧化镓膜制备了大量氮化镓纳米线,X射线衍射、扫描电子显微镜和透射电子显微镜观察发现,纳米线具有十分光滑且干净的表面,其直径为20～60 nm左右,长度达到十几微米.高分辨透射电子显微镜和选区电子衍射分析结果表明,制备的氮化稼纳米线为六方纤锌矿结构.光致发光谱显示制备的氮化稼纳米线有良好的发光特性.另外,简单讨论了氮化稼纳米线的生长机制.     

表面活性剂辅助水热法制备ZnS纳米线

用十二烷基硫醇做表面活性剂,用水热法在180℃,12 h条件下制备了ZnS纳米线.实验发现硫醇可以诱导ZnS纳米粒子沿着一维方向生长.所得产物ZnS纳米线为六方纤锌矿结构,直径为50 nm～100 nm,长度10 μm～20 μm.用X射线衍射(XRD)、透射电子显微镜(TEM)、扫描电子显微镜(SEM)、荧光发射光谱(PL)和紫外漫反射光谱(UV)等手段对所得纳米线进行了表征,并初步探讨了硫醇在限制ZnS纳米晶一维方向生长的机理.     

氨化磁控溅射Ga2O3/BN薄膜制备GaN纳米棒

利用射频磁控溅射技术在Si(111)衬底上制备Ga2O3/BN薄膜,在氨气中退火合成了大量的一维GaN纳米棒.用X射线衍射(XRD)、选区电子衍射(SAED)、傅立叶红外透射谱(FTIR)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和光致发光谱(PL)对样品的晶体结构、元素成分、形貌特征和光学特性进行了分析.结果表明:GaN纳米棒为六方纤锌矿结构的单晶相,其直径在150 nm～400 nm左右,长度可达几十微米.室温下光致发光谱的测试发现了较强的372nm处的强紫外发光峰和420nm处的蓝色发光峰.     

氨化磁控溅射Ga2O3/BN薄膜制备GaN纳米棒

利用射频磁控溅射技术在Si(111)衬底上制备Ga2O3/BN薄膜,在氨气中退火合成了大量的一维GaN纳米棒.用X射线衍射(XRD)、选区电子衍射(SAED)、傅立叶红外透射谱(FTIR)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和光致发光谱(PL)对样品的晶体结构、元素成分、形貌特征和光学特性进行了分析.结果表明GaN纳米棒为六方纤锌矿结构的单晶相,其直径在150 nm～400 nm左右,长度可达几十微米.室温下光致发光谱的测试发现了较强的372nm处的强紫外发光峰和420nm处的蓝色发光峰.     

溶胶-凝胶法制备GaN颗粒

以醇酸镓Ga(OC2H5)3作前驱体,利用溶胶-凝胶法和高温氨化法相结合,成功的合成了GaN粉末.用X射线衍射(XRD)、扫描电子显微镜(SEM)、选择区电子衍射(SAED)、光致发光谱(PL)对粉末的结构、形貌和发光特性进行了表征.结果表明:在950℃时,可以得到纯度较高的GaN粉末且采用该工艺合成的GaN粉末粒度较均匀,生成的GaN多晶絮状颗粒为六方纤锌矿结构,室温下光致发光谱的测试结果发现了较强的402 nm处的近带边发光峰和460 nm处的蓝色发光峰.     

溶胶-凝胶法制备GaN颗粒

以醇酸镓Ga(OC2H5)3作前驱体,利用溶胶-凝胶法和高温氨化法相结合,成功的合成了GaN粉末.用X射线衍射(XRD)、扫描电子显微镜(SEM)、选择区电子衍射(SAED)、光致发光谱(PL)对粉末的结构、形貌和发光特性进行了表征.结果表明在950℃时,可以得到纯度较高的GaN粉末且采用该工艺合成的GaN粉末粒度较均匀,生成的GaN多晶絮状颗粒为六方纤锌矿结构,室温下光致发光谱的测试结果发现了较强的402 nm处的近带边发光峰和460 nm处的蓝色发光峰.     

氨化合成一维GaN纳米线

用氨化溅射Ga2O3薄膜的方法，成功地合成了一维GaN纳米线。用X射线衍射仪(XRD)、扫描电镜(SEM)、透射电镜(TEM)和高分辨电镜(HRTEM)对样品进行了分析。生成的GaN纳米线平直光滑，其直径为20nm～90nm，长可达50μm；纳米线为高质量的单晶六方纤锌矿GaN，沿[110]方向生长。用此工艺制备GaN纳米线，避免了在制备过程中引入杂质，合成的纳米线纯度较高。     

以CuSe纳米粒子为催化剂制备超长ZnSe纳米线

采用化学气相沉积的方法,以Zn粉末为原料,CuSe纳米粒子为催化剂,在Si衬底上成功制备了毫米级ZnSe纳米线。用X射线衍射、EDS和SEM对产物的结构、成分和形貌进行了测试与表征。结果表明：生长的ZnSe纳米线为立方闪锌矿结构,长度达0.35～0.7mm,Zn和Se的摩尔比为1？0.97,其室温光致发光谱显示在325nm波长激发下,ZnSe纳米线在439nm处呈现自由激子的强烈发射,表明生长的ZnSe纳米线具有高的结晶质量。纳米线生长符合氧化还原反应下的气液固生长机制,并证明Cu3Zn合金充当了实际的ZnSe纳米线生长催化剂。     

水热法制备掺Mn的ZnS纳米线及其磁学性能

采用水热法在低温下制备了MnxZn1-xS纳米线.MnxZn1-xS纳米线的形貌和微观结构用透射电子显微镜和X射线衍射仪进行表征.磁性能用振动样品磁强计进行测试.MnxZn1-xS的形貌取决于Mn的含量和在ZnS纳米粒子内外的分布.未掺杂Mn的ZnS纳米线的直径和长度分别为80～200nm和10～20μm.随着Mn含量的增加,MnxZn1-xS纳米线的平均直径逐渐增加,长径比不断减小.X射线衍射结果表明MnxZn1-xS纳米结构结晶性好,为六方纤锌矿结构.在Mn的掺杂量为0.25%时,矫顽力达到最大.随着Mn掺杂量的增加,饱和磁化强度也不断非线性增强.     

Zn0.95Co0.05O纳米线和纳米管的电泳沉积法可控合成（英文）

以阳极氧化铝为模板通过电泳沉积法制备Zn0.95Co0.05O纳米线和纳米管,并对电泳沉积法制备纳米线(管)的机理进行研究。系统的结构表征表明所得的纳米管和纳米线是由8～15nm的纤锌矿纳米晶构成的多晶结构,Co2+离子以代位掺杂形式掺入晶格,取代了晶格中的Zn2+离子。磁性表征显示制备的纳米线和纳米管具有室温铁磁性。由于Co在纳米线(管)中表面择优分布,纳米管的磁性明显高于纳米线。     

氨化Ga2O3 /Nb膜制备的GaN纳米线的光学和微观结构特性的研究

采用射频磁控溅射技术在硅衬底上制备Ga2O3/Nb薄膜,然后在900℃下于流动的氨气中进行氨化制备GaN纳米线.用X射线衍射(XRD)、透射电子显微镜(TEM)和高分辨透射电子显微镜详细分析了GaN纳米线的结构和形貌.结果表明:采用此方法得到的GaN纳米线有直的形态和光滑的表面,其纳米线的直径大约50nm,纳米线的长约几个微米.室温下以325nm波长的光激发样品表面,只显示出一个位于367 nm的很强的紫外发光峰.最后,简单讨论了GaN纳米线的生长机制.     

Synthesis of one-dimensional GaN nanorods by Tb intermediate layer with different thicknesses

GaN nanorods were synthesized by magnetron sputtering and ammonification system, and the thickness of Tb intermediate layer was changed to study the effect on GaN nanorods. The resultant was tested by scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and photoluminescence (PL) spectra. The results show that the thickness of Tb layer has an evident effect on the modality, quality, and luminescence properties of GaN nanorods. PL spectra at room temperature show a very strong emission peak at 368 nm and a weak emission peak at 387 nm, and the intensities of the peak for the produced samples reach the maximum when Tb layer is 20 nm. Finally, the optimal thickness of 20 nm of Tb intermediate layer for synthesizing GaN nanostructures is achieved.     

Effect of ammoniating temperature on microstructure and optical properties of one-dimensional GaN nanowires doped with magnesium

One-dimensional GaN nanowires doped with Mg element have been successfully prepared on Si (1 1 1) substrates by magnetron sputtering through ammoniating Ga₂O₃/Mg thin films, and the effect of the ammoniating temperatures on the microstructure and optical properties of the GaN nanowires was investigated in detail. X-ray diffraction (XRD), X-ray photoelectron spectroscope (XPS), FT-IR spectrophotometer, Scanning electron microscope (SEM), high-resolution transmission electron microscope (TEM), and photoluminescence (PL) spectrum were carried out to characterize the microstructure, morphology, and optical properties of GaN nanowires. The results demonstrate that ammoniating temperature has a significant effect on microstructure, morphology and optical properties of GaN nanowires. GaN nanowires after ammoniation at 900 °C for 15 min are straight, smooth and of uniform thickness along spindle direction with the highest crystalline quality. The growth direction of these nanowires is parallel to [1 0 0] orientation.     

Low temperature solution-synthesis and photoluminescence properties of ZnO nanowires

A general and simple approach has been developed to prepare zinc oxide (ZnO) nanowires from commercially available zinc acetate precursors using a solution-phase reaction. The influence of post-annealing temperature on the morphology of the zinc oxides nanowires was also investigated. Using X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) studies, we confirm that the ZnO nanowires are highly crystalline in nature with preferential orientation in the c-axis direction, with nanowire diameters of around 30–60 nm. The photoluminescence (PL) studies demonstrate a strong UV luminescence band around 382 nm, and three weak, broad bands at 454, 468, and 510 nm, respectively, in the blue and green range. After being annealed under an air atmosphere, the products show an apparent red-shift in the UV emission band. The intensity of the defect-related emission bands was significantly suppressed.     

Growth and optical properties of gallium nitride nanowires produced via different routes

Several vapor phase processes for the preparation of GaN nanowires, such as chemical vapor deposition (CVD), direct reaction (DR), and hydride vapor phase epitaxial growth (HVPE), have been previously reported. To determine the most appropriate route for fabrication and engineering of GaN nanowires, we prepared nanowires via the three aforementioned routes and characterized their microstructures and photoluminescence (PL) properties. All prepared nanowires were single-crystalline, whowing well-defined crystal structure in X-ray diffraction and transmission electron microscopic analyses. However, high-quality nanowires could most readily be obtained by DR. Large-scale and selective area growth of nanowires could most readily be achieved by CVD and HVPE. PL spectra for the nanowires prepared by HVPE showed a red-shifted center wavelength and wider full width-half maximum (FWHM) value as compared to those prepared by DR or CVD. This indicates the presence of unknown impurities and/or defects in the nanowires prepared by HVPE. Our results indicate that high-quality nanowires can be prepared by DR and CVD, while large-scale selective growth can be achieved by CVD and HVPE.     

碳热法合成具有蓝光发射特性的氧化镓纳米线、纳米带和纳米片

利用碳纳米管通过碳热法合成了氧化镓纳米线、纳米带和纳米片。采用扫描电镜和透射电镜对其进行了形态和结构表征。合成的氧化镓纳米结构是单晶体。室温光致发光谱分析发现，氧化镓纳米晶在蓝光区域487nm处产生明显的发射峰。     

Catalytic Growth of Large-Scale GaN Nanowires

A novel lanthanon seed was employed as the catalyst for the growth of GaN nanowires. Large-scale GaN nanowires have been synthesized successfully through ammoniating Ga₂O₃/Tb films sputtered on Si(111) substrates. Scanning electron microscopy, x-ray diffraction, high-resolution transmission electron microscopy, and Fourier transform infrared spectroscopy were used to characterize the samples. The results demonstrate that the nanowires are single-crystal hexagonal wurtzite GaN. The growth mechanism of GaN nanowires is also discussed.     

Si（111）衬底上生长GaN晶环的研究

利用热壁化学气相沉积在Si(111)衬底上获得GaN晶环，采用扫描电镜(SEM)、选择区电子衍射(SAED)、X射线衍射(XRD)，光致发光(PL)谱和傅里叶红外吸收谱(FTIR)对晶环的组成、结构、形貌和光学特性进行分析。初步结果证明：在Si(111)衬底上获得择优生长的六方纤锌矿结构的GaN晶环。SEM显示在均匀的薄膜上出现直径约为10μm的5品环，由XRD和SAED的分析证实晶环呈六方纤矿多晶结构，FTIR显示GaN薄膜的主要成分为GaN，同时含有少量的C污染，PL测试表明晶环呈现不同于GaN薄膜的发光特性。     

Preparation and Properties of GaN Micro-Ribbons on Ga-Diffused Si （111） Substrates

用射频磁控溅射工艺在室温扩镓硅衬底上沉积Ga2O3膜,然后在氨气气氛下氮化Ga2O3膜得到GaN微米带,用X射线衍射(XRD)、扫描电镜(SEM)、选区电子衍射(SAED)、X射线光电子能谱(XPS)及光致发光谱(PL)对薄膜样品进行了结构、表面形貌、组分及发光特性分析.SEM图像显示直径约为100 nm～300 nm微米带随机分布在GaN薄膜表面.XRD、XPS及SAED分析表明GaN微米带呈六方闪锌矿多晶结构,择优沿[001]方向生长.P1显示了可能由量子限制效应引起的发光峰,其相对于报道的GaN晶体发光峰有显著蓝移.