National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8565, Japan.
Nat Chem. 2009 Aug;1(5):415-8. doi: 10.1038/nchem.282. Epub 2009 Jul 5.
Visualizing atoms and discriminating between those of different elements is a goal in many analytical techniques. The use of electron energy-loss spectroscopy (EELS) in such single-atom analyses is hampered by an inherent difficulty related to the damage caused to specimens by incident electrons. Here, we demonstrate the successful EELS single-atom spectroscopy of various metallofullerene-doped single-wall nanotubes (known as peapods) without massive structural destruction. This is achieved by using an incident electron probe with a low accelerating voltage (60 kV). Single calcium atoms inside the peapods were unambiguously identified for the first time using EELS. Elemental analyses of lanthanum, cerium and erbium atoms were also demonstrated, which shows that single atoms with adjacent atomic numbers can be successfully discriminated with this technique.
可视化原子并区分不同元素的原子是许多分析技术的目标。在这种单原子分析中，电子能量损失光谱（EELS）的使用受到与入射电子对样品造成的损坏有关的固有困难的阻碍。在这里，我们展示了各种金属富勒烯掺杂的单壁纳米管（称为豌豆荚）的成功的 EELS 单原子光谱学，而没有大规模的结构破坏。这是通过使用具有低加速电压（60kV）的入射电子探针来实现的。首次使用 EELS 明确识别了豌豆荚内的单个钙原子。还进行了镧、铈和铒原子的元素分析，这表明可以成功地用该技术区分相邻原子数的单个原子。
