Tuning the electrocatalytic activity and durability of low cost Pd70Co30 nanoalloy for oxygen reduction reaction in fuel cells

The factors controlling the electrocatalytic activity for the oxygen reduction reaction (ORR) in fuel cells have been tuned and investigated systematically with the low cost carbon-supported Pd70Co30 nanoalloy. The catalytic activity decreases with increasing annealing temperature due to an increasing degree of alloying (Co content in the Pd lattice) and crystallite size. With a controlled crystallite size of ∼8 nm, the activity is found to decrease with increasing degree of alloying from 18 to 30 at.% Co. However, the catalyst durability increases considerably with annealing temperature due to the alloying of Pd with Co and an increase in crystallite size.