| Abstract: | Bimetallic clusters can display new characteristics that cannot be obtained by varying either the size of pure metallic systems or the composition of bulk bimetals. We have demonstrated that both copper (Cu)-rich core/gold (Au)-rich shell and Au-rich/Cu-rich shell clusters can be prepared using the radio frequency (RF) magnetron-sputtering gas phase cluster beam synthesis method with subsequent mass selection. Here we present an aberration-corrected scanning transmission electron microscopy (STEM) study of the ageing of the deposited clusters. We find that the Au-rich core/Cu-rich shell structure is unstable against both storage in vacuum and exposure to air, losing the Cu-rich shell. However, the Cu-rich core/Au-rich shell structure is found to be much more stable, even when exposed to air. |
