Atomic imaging of the motion and transformation of Pt3Ni nanoparticles in liquids

Abstract

It is important to elucidate how nanoscale particles move in a liquid for mass transport in confined liquids. In this work, we used liquid cell TEM to observe the motion and transformation pathways of Pt₃Ni nanoparticles in solution by systematically changing the electron beam dose rate. The Pt₃Ni nanoparticles firstly underwent 3D motion at a low electron beam dose rate. When the electron beam dose rate increased, the segregation process was shown, in which a thin Ni layer was segregated from Pt₃Ni nanoparticles on the atomic scale. More interestingly, small Pt₃Ni nanoparticles could assemble into a long nanowire at a higher electron beam dose rate. This work is expected to assist future controlled synthesis and applications of alloy nanostructures.