电子束对纳米材料辐照损伤的电镜研究

文中探讨了用透射电子显微镜观察纳米材料时，在不同的放大倍数下，电子束的辐照损伤对纳米材料在电镜观察时的影响。文中以纳米碳酸钙的电镜照片和电子衍射花样为例说明了电子束的辐照损伤对纳米材料在形貌和结构上造成的破坏：放大倍数越大、照射时间越长，电子束对样品的损伤越严重。本研究采用在纳米颗粒表面蒸镀一层适当厚度的碳膜的方法，有效地减少了电子束辐照损伤对纳米粒子结构和形态的影响，获得了纳米材料不失真的形貌和结构的电镜照片。

A study of electron-bean radiation-damage on nano-materials by TEM

The damage-effect on nanosized calcium carbonate caused by electron-beam radiation was observed by using TEM under different magnifications and various time periods of exposure to radiation. The different damaging-mechanisms on morphologies and structures of nanosized calcium carbonate were studied by observing its micrograph and diffraction patterns. It is concluded that the higher the magnification or the longer the exposure time, the severer the damage on the sample is. In the research, a thin carbon film was coated on the surface of the samples which effectively reduced the radiation damage to the morphology and structure of the samples, and a fidelity image of the nano-materials is obtained.