Metal-Metal Binary Nanoparticle Superlattices: A Case Study of Mixing Co and Ag Nanoparticles

Here, Co/Ag binary nanopartide superlattices were engineered. It is demonstrated that the Ag/Co nanopartide size ratio is the dominating factor in the formation of binary nanopartide superlattices. However, regardless of the relative ratio concentration of Co and Ag nanoparticles, the deposition temperature, T-d markedly changes the crystalline structure of binary superlattices. A systematic study of these parameters is presented in order to shed light on the driving force in the formation of binary metallic nanopartide superlattices. For metal Co and Ag nanoparticles, the interparticle potential pairs are considered to be strong, but entropy is still the main driving force for the assembling into binary nanopartide superlattices, rather than the energy arising from the interparticle interactions.