Title : Controlled generation of binary nanoparticles for catalysis research
Abstract:
Heterogeneous and electrochemical catalysis is a diverse area of research that finds applications in clean energy technology and the reduction of environmental pollution. Among many metals, the current best catalysts typically rely on critical materials, such as platinum (Pt). As per the EU list of critical raw materials for 20171, Pt needs to be reduced/replaced with abundant materials. Here we present our results on the study of precision nanoalloy particles with the ultimate objective of Pt reduction.
Pt-Cu bimetallic clusters have been produced via gas phase, ligand-free synthesis; in particular we used two new generation cluster sources: the multiple ions cluster source (MICS)2 and the matrix assembly cluster source (MACS)3. The conventional magnetron-based cluster source is based on the sputtering of a single pure or alloy target under vacuum conditions with subsequent cluster aggregation via further collision with the aggregation gas. In the MICS the single magnetron is replaced with three independent magnetrons allowing the production of a wide range of nanoalloy clusters starting from pure targets. The great advantage of this source is the possibility to growth a wide range of samples via the controlled sputtering of pure targets, controlling both their structure (alloys, core@shell and shell@core) and composition by changing the mutual magnetron positions as well as their sputtering rate. For the present study we deposited binary Pt-Cu clusters with the same size and compositions, but different structures: alloy, core@shell and shell@core, in order to investigate the effect of the nanostructures on gas-phase catalytic and electro catalytic performance.
