In situ observation of morphological change of Pd-based bimetallic nanoparticles synthesized by co-sputtering

The formation process of Pd-based bimetallic nanoparticles synthesized by co-sputtering is investigated by performing in situ morphological observation using resistive spectroscopy. The segregation of the metal with lower surface energy on the nanoparticle surface is observed, and it is found that the formation process of the alloy nanoparticles tends to be similar to that of the nanoparticles composed of the core metal even when the atomic fraction of the shell metal is higher than that of the core metal. The co-sputtering process is simulated by the molecular dynamics analysis, and the observed formation process is theoretically confirmed.