Gas phase synthesis of Mo-Cuo heterostructured nanoparticles: a TEM study

G. Krishnan, G. Palasantzas, B.J. Kooi
University of Groningen, NL

Keywords: core-shell nanoparticles, gas phase synthesis

Summary:

Heterostructured nanoparticles offer great opportunities for applications in areas such as biomedicine, renewable energy and data storage by virtue of their embedded multiple functionalities and enhanced magnetic, catalytic and optical performance arising from the interactions of the individual components within the nanoparticles. Here, we demonstrate the binary metallic(Mo-Cu) with distinctively different heterostructures at the single particle level can be prepared directly in the gas phase. By tuning the synthesis condition we can produce Mo-Cu in the form of core-shell to dumbell shaped structures. Figure 1 (a) shows the bright field TEM image of the Mo-Cu core shell nanoparticles. Figure 1(b) shows the dumbell shaped Mo-Cu nanoparticles. From the HRTEM, EDX and HAADF analysis the Mo is present in the core and the Cuo in the outer shell.(figure 2) The posibility of tuning these structure in the gas phase has been achieved via surface seggregation of Mo and Cu. Also tuning the synthesis condition such as sputtering gas pressure,and bias applied to the target can change the nanoparticles shape from spherical to cube with controlled shell thickness. As this synthesis method is UHV compatible, it yields a high quality interfaces and surfaces which is one of its important advantage compared with other established methods for producing heterostructured nanoparticles.