Pt-Based Bimetallic Alloy Nanoparticles: Composition Control and Formation Mechanism
Elina Chockler
Department of Chemistry, Ben-Gurion University of the Negev
Platinum is an excellent catalyst, widely used in many applications such as catalytic converters and fuel cells. In many applications, Pt nanoparticles are used due to their high surface area which increases the activity of the catalyst. Despite its many advantages, platinum has a few shortcomings including: 1) Poisoning of Pt by species such as CO, which lowers the catalytic activity of Pt with time. 2) The high cost of Pt. One approach that has been shown to improve the activity of platinum catalysts is the addition of another metal to the Pt nanoparticles to form an alloy or a heterostructure (core- shell, dimer, etc.). This structure has a lower cost compared to pure Pt. Our research focuses on creating a library of Pt-based bimetallic alloy nanoparticles with various compositions, sizes and shapes.
We synthesized PtAu, PtPd and PtCu nanoparticles with various compositions. The shape, size and composition of the particles are characterized by transmission electron microscopy, energy- dispersive X-ray spectroscopy, and X-ray diffraction. We have conducted a detailed study on the formation mechanism of PtCu nanoparticles by studying the growth kinetics of PtCu nanoparticles. Few parameters were changed to study the growth mechanism of PtCu nanoparticles, such as metal salts, temperature and ligand concentration, which have a direct influence on the growth kinetics.
