3C-SiC又称β-SiC,有着优异的耐高温、耐腐蚀、耐辐照性能,是反应堆这类复杂环境中的理想材料。近年来,一维碳化硅纳米线材料成为碳化硅材料研究领域的热门研究方向,同时也面临加工手段匮乏、加工难度大的问题。我们通过化学气相沉积法...3C-SiC又称β-SiC,有着优异的耐高温、耐腐蚀、耐辐照性能,是反应堆这类复杂环境中的理想材料。近年来,一维碳化硅纳米线材料成为碳化硅材料研究领域的热门研究方向,同时也面临加工手段匮乏、加工难度大的问题。我们通过化学气相沉积法成功制备了含有高密度堆叠层错的3C-SiC纳米线,并采用扫描电子显微镜(Scanning Electron Microscope,SEM)、透射电子显微镜(Transmission Electron Microscope,TEM)、X射线衍射(X-Ray Diffraction,XRD)以及拉曼光谱(Raman spectrum)等多种手段对制备出来的碳化硅纳米线进行了微观结构表征,揭示了其独特的微观形态和晶体结构特征;进一步研究了超声裁剪碳化硅纳米线,利用“气泡-射流”模型结合碳化硅纳米线的形态解释了碳化硅纳米线的超声裁剪过程,探索了碳化硅纳米线的直径、强度、缺陷等对其在超声过程中断裂行为的影响。本研究为碳化硅纳米线的超声裁剪加工和纳米线的强度研究提供了新的视角,对于未来碳化硅纳米线在核能领域的应用具有重要的意义。展开更多
CoSb3 nanowire arrays, preferred orientation of [510], were fabricated by electrodeposition of Co2+ and Sb3+ into anodic aluminum oxide (AAO) templates. The morphologies, structure, and composition of the as-synthesiz...CoSb3 nanowire arrays, preferred orientation of [510], were fabricated by electrodeposition of Co2+ and Sb3+ into anodic aluminum oxide (AAO) templates. The morphologies, structure, and composition of the as-synthesized sample have been performed using X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and energy-dispersive X-ray spectroscopy (EDS). Based on the previous investigation on CoSb3 nanowire arrays orientated along [420], the formation mechanism for different preferential orientation nanowire arrays was discussed.展开更多
LaF3 nanowires with high aspect ratios have been prepared via a low-temperature solvothermal method using LaCl3 and KF or NH4F as starting materials in absolute alcohol at 160 ℃ for 12 h. XRD pattern and TEM images s...LaF3 nanowires with high aspect ratios have been prepared via a low-temperature solvothermal method using LaCl3 and KF or NH4F as starting materials in absolute alcohol at 160 ℃ for 12 h. XRD pattern and TEM images show that the products are hexagonal structure with diameter of 80 nm and length up to 8 μm. The lanthanum sources played most important roles, reaction temperature and time also played important roles in the morphology control of final LaF3 products. The optimal conditions for ideal LaF3 nanowire are at a reaction temperature of 160 ℃ and reaction time for 14 h using LaCl3 and NH4F as starting materials. A possible formation mechanism for LaF3 nanowires is proposed.展开更多
文摘3C-SiC又称β-SiC,有着优异的耐高温、耐腐蚀、耐辐照性能,是反应堆这类复杂环境中的理想材料。近年来,一维碳化硅纳米线材料成为碳化硅材料研究领域的热门研究方向,同时也面临加工手段匮乏、加工难度大的问题。我们通过化学气相沉积法成功制备了含有高密度堆叠层错的3C-SiC纳米线,并采用扫描电子显微镜(Scanning Electron Microscope,SEM)、透射电子显微镜(Transmission Electron Microscope,TEM)、X射线衍射(X-Ray Diffraction,XRD)以及拉曼光谱(Raman spectrum)等多种手段对制备出来的碳化硅纳米线进行了微观结构表征,揭示了其独特的微观形态和晶体结构特征;进一步研究了超声裁剪碳化硅纳米线,利用“气泡-射流”模型结合碳化硅纳米线的形态解释了碳化硅纳米线的超声裁剪过程,探索了碳化硅纳米线的直径、强度、缺陷等对其在超声过程中断裂行为的影响。本研究为碳化硅纳米线的超声裁剪加工和纳米线的强度研究提供了新的视角,对于未来碳化硅纳米线在核能领域的应用具有重要的意义。
文摘CoSb3 nanowire arrays, preferred orientation of [510], were fabricated by electrodeposition of Co2+ and Sb3+ into anodic aluminum oxide (AAO) templates. The morphologies, structure, and composition of the as-synthesized sample have been performed using X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and energy-dispersive X-ray spectroscopy (EDS). Based on the previous investigation on CoSb3 nanowire arrays orientated along [420], the formation mechanism for different preferential orientation nanowire arrays was discussed.
文摘LaF3 nanowires with high aspect ratios have been prepared via a low-temperature solvothermal method using LaCl3 and KF or NH4F as starting materials in absolute alcohol at 160 ℃ for 12 h. XRD pattern and TEM images show that the products are hexagonal structure with diameter of 80 nm and length up to 8 μm. The lanthanum sources played most important roles, reaction temperature and time also played important roles in the morphology control of final LaF3 products. The optimal conditions for ideal LaF3 nanowire are at a reaction temperature of 160 ℃ and reaction time for 14 h using LaCl3 and NH4F as starting materials. A possible formation mechanism for LaF3 nanowires is proposed.
基金National"973"Project(2007CB936601)National Natural Science Foundation(50872064)of China+2 种基金Knowledge Innovation Project of Chinese Academy of Sciences(KGCX2-YW-341)China Postdoctoral Science Foundation(20090450581)K.C.Wong Education Foundation,Hong Kong
