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1.
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. 相似文献
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ZHUANGHuizhao GAOHaiyong XUEChengshan WANGShuyun DONGZhihua HEJianting 《稀有金属(英文版)》2005,24(2):110-114
GaN nanorods have successfully been synthesized on Si(111) substrates via ammoniating ZnO/Ga2O3 films at 950℃. Ga2O3 thin films and ZnO middle layers were deposited in turn on Si(111) substrates by r.f. magnetron sputtering system. ZnO volatilized at 950℃ in the ammonia ambience and Ga2O3 reacted to NH3 to fabricate GaN nanorods in the later ammoniating process. The volatilization of ZnO layers played an important role in the fabrication. The structure and composition of the GaN nanorods were studied by X-ray diffraction (XRD) and Fourier transform infrared spectrophotometer (FTIR). The orphology ofGaN nanorods was investigated using scanning electron microscopy (SEM) and transmission electronic microscope (TEM). The analyses of measured results revealed that GaN nanorods with hexagonal wurtzite stxucture were prepared by this method. 相似文献
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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. 相似文献
4.
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. 相似文献
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以硝酸锌(Zn(NO3)2·6H2O)、和钨酸钠(Na2WO4·2H2O)作为起始反应物,利用微波水热法在200℃下合成纳米棒状钨酸锌。利用X-射线粉末衍射、场发射扫描电子显微镜、透射电子显微镜及能谱成分图谱等分析手段对纳米棒状钨酸锌粉体进行表征,并对不同Ag+掺杂量的ZnWO4纳米棒的光催化性能进行了研究。结果表明:Ag+成功的掺入ZnWO4纳米棒中;随着Ag+掺杂量的增加ZnWO4纳米棒的颗粒尺寸也不断增大;Ag+掺杂量2%时纳米棒状钨酸锌粉体的光催化性能最优,但是随着掺杂量的逐渐增加光催化性能反而降低。 相似文献
7.
ZHANGYue DAIYing HUANGYunhua ZHOUCheng 《稀有金属(英文版)》2004,23(1):26-26
Some types of ZnO nanostructures with various shape and size, including tetrapod-like ZnO (T-ZnO) nanorods, nanowires and nanonbbons, have been obtained by controlled growth process. The nanostructures of ZnO have been investigated by means of field-emission scanning electron microscope, transmission electron microscopy and high-resolution transmission electron microscopy. The growth mechanisms of various ZnO nanostructures were proposed and discussed. 相似文献
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Jin Chen Jin LiJiahui Li Guoqing XiaoXiaofeng Yang 《Journal of Alloys and Compounds》2011,509(3):740-743
Uniform ZnO nanorods with a gram scale were prepared by a low temperature and solution-based method. The samples are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and photoluminescence (PL). The results showed that the sample had uniform rod-like morphology with a narrow size distribution and highly crystallinity. Room-temperature PL spectra of these nanorods show an exciton emission around 382 nm and a negligible deep level emission, indicating the nanorods have high quality. The gas-sensing properties of the materials have been investigated. The results indicate that the as-prepared nanorods show much better sensitivity and stability. The n-type semiconductor gas sensor exhibited high sensitivity and fast response to ethanol gas at a work temperature of 400 °C. ZnO nanorods are excellent potential candidates for highly sensitive gas sensors and ultraviolet laser. 相似文献
10.
YANG Li XUE Chengshan WANG Cuimei LI Huaixiang REN Yuwen) Chemistry Function Materials Lab Institute of Semiconductors Shandong Normal University Jinan China) Physics Department Shandong Normal University Jinan China) Inspection Institute for Electronic Products of Shandong Jinan China 《稀有金属(英文版)》2003,22(3)
Hexagonal gallium nitride films were successfully fabricated through ammoniating Ga2O3 films deposited on silicon (111) substrates by electrophoresis. The structure, composition, and surface morphology of the formed films were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The measurement results reveal that the polycrystalline GaN films with hexagonal wurtzite structure were successfully grown on the silicon (111) substrates. Preliminary results suggest that varying the ammoniating temperature has obvious effect on the quality of the GaN films formed with this method. 相似文献
11.
采用化学浴沉积法制备了高纵横比的CdS纳米棒。二苯硫腙(DPTA)作为有机添加剂用于合成CdS纳米棒。用X射线衍射(XRD)和透射电子显微镜(TEM)表征样品的结晶性能和微观结构。XRD结果表明,样品中同时存在六角相和立方相,当pH值为10.5时,六角相CdS的(111)峰的衍射强度最大,同时出现立方相CdS。TEM结果显示,可以通过调节pH值控制CdS纳米晶的形貌,当pH值为10.5时,CdS纳米棒的纵横比最大,直径约50nm,长约3μm。对CdS纳米晶电学性能的研究表明,与用PVA作为添加剂和在纯乙醇中制备的CdS纳米棒相比,用DPTA作为添加剂制备的CdS纳米棒具有更低的电阻值。这是因为DPTA分子中存在2个大π键,有利于电子的传输。还讨论了CdS纳米棒的生长机理和DPTA修饰CdS纳米棒中的电子转移。 相似文献
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采用水热后处理方法将片状、共价键结合的有机-无机复合硫化物ZnS·0.5en放入热液中热解,制备六方纤锌矿结构ZnS纳米棒,利用X射线衍射仪、透射电子显微镜、红外吸收光谱仪分析了水热后处理对ZnS的晶体生长和结构形貌的影响.结果表明ZnS纳米棒是单晶结构,长度达1μm,直径约有30~40nm.纳米ZnS纳米棒的生长符合溶剂配位分子模板机理. 相似文献
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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。 相似文献
14.
Beata Zielińska Ewa Borowiak-PalenBarbara Grzmil Ryszard J. Kalenczuk 《Journal of Alloys and Compounds》2011,509(17):5414-5419
Titanate nanorods with high photocatalytic activity was successfully synthesized through a simple catalyst-free hydrothermal method. The photocatalytic degradation of a model organic dye (Reactive Red 198) was accelerated by the calcination of the nanorods prior the reaction. The calcination of nanorods did not modify their morphology, however the crystallinity of the samples was significantly improved. Therefore, the quality of the samples is a key parameter determining their activity in the investigated photocatalytic process. The as-produced and annealed catalysts were characterized by high-resolution transmission electron microscopy (HR-TEM), X-ray diffraction (XRD), Diffuse Reflectance (DR) UV-Vis and resonance Raman spectroscopy. 相似文献
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B. Song J.K. Jian G. Wang M. Lei H.Q. Bao X.L. Chen 《Journal of Alloys and Compounds》2008,460(1-2):31-35
The GaN powders were synthesized by the reaction of Ga2O3 and Li3N and scanning transmission electron microscopy (STEM) analysis showed the as-prepared GaN were N-deficient with the N vacancies reaching as much as 21%. Besides single-phase of the hexagonal GaN, no other phase from impurities can be detected under the high-resolution transmission electron microscopy (HRTEM) observations. The room temperature (RT) frequency spectrums of the relative dielectric constants r were measured and the N-deficient GaN exhibited at least twofold enhancement than that of GaN nanostructure materials, especially at low frequency range. Because of the great number of N vacancies (VN), the rotation direction polarization (RDP) contributes mostly for the enhancement of r in N-deficient GaN. 相似文献
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SUNZhencui CAOWentian WEIQinqin WANGShuyun XUEChengshan SUNHaibo 《稀有金属(英文版)》2005,24(2):194-199
Hexagonal GaN films were prepared by nitriding Ga2O3 films with flowing ammonia. Ga2O3 films were deposited on Ga-diffused Si (111) substrates by radio frequency (r.f.) magnetron sputtering. This paper have investigated the change of structural properties of GaN films nitrided in NH3 atmosphere at the temperatures of 850, 900, and 950℃ for 15 min and nitrided at the temperature of 900℃ for 10, 15, and 20 rain, respectively. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) were used to analyze the structure, surface morphology and composition of synthesized samples. The results reveal that the as-grown films are polycrystalline GaN with hexagonal wurtzite structure and GaN films with the highest crystal quality can be obtained when nitrided at 900℃ for 15 min. 相似文献
18.
研究了Ga2O3/Al2O3膜反应自组装制备GaN薄膜。首先利用磁控溅射法在硅衬底上制备Ga2O3/Al2O3膜,再将Ga2O3/Al2O3膜在高纯氨气气氛中氨化反应得到了GaN薄膜。用X射线衍射(XRD),X光光电子能谱(XPS)、扫描电镜(SEM)、透射电镜(TEM)和荧光光谱(PL)对样品进行结构、组分、形貌和发光特性的分析。测试结果表明:用此方法得到了六方纤锌矿结构的GaN晶体膜。 相似文献
19.
NiFe2O4 nanorods have been successfully synthesized via thermal treatment of the rod-like precursor fabricated by Ni-doped α-FeOOH,which was enwrapped by the complex of citric acid and Ni2+.The morphology evolution during the calcination of the precursor nanorods was investigated with transmission electron microscopy(TEM),and the phase and the magnetic properties of samples were analyzed through X-ray diffraction(XRD) and vibrating sample magnetometer(VSM).The results indicated that the diameter of the NiFe2O4 nanorods obtained ranged between 30 and 50 nm,and the length ranged between 2 and 3 μm.As the calcination temperature was up to 600℃,the coercivity,saturation magnetization,and remanent magnetization of the samples were 36.1 kA·m-1,27.2 A·m2·kg-1,and 5.3 A·m2·kg-1,respectively.The NiFe2O4 nanorods prepared have higher shape anisotropy and superior magnetic properties than those with irregular shapes. 相似文献
20.
以Ln(NO3)3·6H2O(Ln=Ce,Tb)及NaH2PO4·2H2O为原料,乙二醇为溶剂,在微反应器中合成了铈铽共掺杂磷酸镧(LaPO4:Ce3+,Tb2+)纳米发光颗粒.采用X射线衍射仪(XRD)、透射电子显微镜(TEM)和荧光光谱仪对LaPO4:Ce3+,Tb3+纳米发光颗粒的物相、微结构和荧光性能进行了表征.结果表明:LaPO4:Ce3+,Tb3+纳米发光颗粒具有六方晶系的晶体结构,形貌不规则,粒度为20 nm左右、窄的粒度分布的纳米颗粒,并且颗粒分散均匀,具有较强的荧光性能. 相似文献