STRUCTURE-FUNCTION RELATIONS OF PD NANOPARTICLES FOR FUEL CELL ELECTROCATALYSIS

This work provides a study of palladium-based electrocatalysts for proton exchange membrane fuel cells (PEMFCs). Increasing the electrocatalytic oxygen reduction activity while decreasing the Pt loading would greatly enhance the development of PEMFCs. At a fraction of the cost of Pt, Pd provides a potentially viable alternative for PEMFC applications and this provides the impetus for our work. The systematic examination of structure-electrocatalytic properties in monodisperse Pd nanoparticles will involve synthesis, characterization and electrochemistry testing. Morphologically controlled Pd nanoparticles, of different varieties, are synthesized and studied electro-catalytically for oxygen reduction. Morphology is controlled through a one-pot addition technique of three different reagents (precursor, surfactant and reducing agent). By changing the injection sequence of reductant and surfactant: Cubic, multi-armed, and dentritic Pd nanoparticles are selectively obtained. Characterization of the nanoparticles was carried out using techniques; including Transmission Electron Microscopy (TEM), and X-Ray Diffraction (XRD). Oxygen reduction reaction, ORR, experiments were implemented using a three-electrode electrochemical cell set-up. The electrodes consist of a reference electrode (saturated calomel electrode), a counter electrode (Pt wire), and a working electrode (ring disk electrode). Through the current that was generated, cyclic voltammetry and linear sweep voltammetry data is collected via a software interface, where the electrocatalytic properties of the material are evaluated and further studies performed