Control of cluster coalescence during formation of bimetallic nanoparticles and nanoalloys obtained via electric explosion of two wires

In this study, the possibility of controlling the coalescence of clusters during the formation of bimetallic nanoparticles and nanoalloys is demonstrated for the first time using joint electric explosion of Nb/Al and Nb/Ag wires under an argon atmosphere as an example. The evolution of clusters in the condensed phase is considered based on the adiabatic approximation to expand the products of the electric explosion of wires. Controlling the temperature and size of the clusters formed under the electric explosion of wires generating the energy necessary for the transition from the metallic state to the two-phase state (clusters of the condensed phase and weakly ionized plasma) allows synthesizing nanoparticles and bimetallic nanoparticles possessing the structures of nanoalloys and Janus particles, respectively. The experimental studies are supplemented by describing structural patterns and segregation phenomena using a hybrid computer experiment that adopts two alternative methods, i.e., the Monte Carlo and molecular dynamics methods. Both methods predict similar structure formation trends, particularly segregation patterns, in Nb-Ag and Nb-Al nanoparticles. For the first time, we have obtained bimetallic nanoparticles possessing a more complex structure, compared to the formerly known core shell, namely the onion-like structure. The Nb-2964-Ag-2964 and Nb-2964-Al-2964 nanoparticles s are characterized by the formation of icosahedral cores and crystalline cores based on the hcp and fcc phases, respectively, over the entire temperature range studied. (C) 2022 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.

Automated summary

This study demonstrates the possibility of controlling cluster coalescence during the formation of bimetallic nanoparticles and nanoalloys through electric explosion, and provides a detailed description of the evolution and structural features of the clusters using experimental and computational simulations. The results show that by controlling the temperature and size of the clusters, nanoparticles and bimetallic nanoparticles with specific structures can be synthesized.