#CORE SHELL NANOSTRUCTURES CRACK#

The researchers say that their work is the highest resolution LC-TEM video ever recorded. 'The finding was very unexpected, but we're very happy with the results,' said Qiubo Zhang, first author and postdoctoral researcher in the Materials Sciences Division.

#CORE SHELL NANOSTRUCTURES CRACK#

However, the direction of growth was guided not by a difference in size but by a crack defect in the shell of the initially larger CSNP. In one key experiment, an LC-TEM video shows a small Cd-CdCl 2 core-shell nanoparticle merging with a large Cd-CdCl 2 CSNP to form a larger Cd-CdCl 2 CSNP. Using a technique called high-resolution liquid cell transmission electron microscopy (LC-TEM) at the Molecular Foundry, the researchers captured real-time, atomic-scale LC-TEM videos of Cd-CdCl 2 CSNPs ripening in solution. New video footage captured by Berkeley Lab scientists reveals for the first time that nanoparticle growth is directed not by difference in size, but by defects.

The researchers exposed the solution with an electron beam to produce Cd-CdCl 2 core-shell nanoparticles (CSNPs)-which look like flat, hexagonal discs-where cadmium atoms form the core, and cadmium chloride forms the shell. We are rewriting textbook chemistry, and it's very exciting,' said senior author Haimei Zheng, a senior scientist in Berkeley Lab's Materials Sciences Division and an adjunct professor of materials science and engineering at UC Berkeley.įor the study, the researchers suspended a solution of cadmium sulfide (CdS) nanoparticles with cadmium chloride (CdCl 2) and hydrogen chloride (HCl) in a custom liquid sample holder.

The scientists recently reported their findings in the journal Nature Communications. According to this theory, small particles dissolve and redeposit onto the surface of large particles, and the large particles continue to grow until all of the small particles have dissolved.īut now, new video footage captured by Berkeley Lab scientists reveals that nanoparticle growth is directed not by difference in size, but by defects.

Core shell nanostructures