Single atom spectroscopy with reduced delocalization effect using a 30 kV-STEM

Abstract

Imaging and chemical analysis of individual metallofullerene molecules were successfully carried out without massive destruction using a scanning transmission electron microscope (STEM) operated at 30 kV. Electron energy-loss spectroscopy (EELS) unambiguously identified the constituent atom of each metallofullerene molecule. The profile of EELS chemical map measured across the single atom provides a rough estimate of EELS signal delocalization, which is considerably reduced using accelerating voltage as low as 30 kV.