A slab model was used to examine the geometric and electronic structure of Pd3Bi based on first principles density functional theory (OFT) calculations. The structural and electronic properties were determined for bulk and slab models. Atomic oxygen was adsorbed on all adsorption sites of (100) Pd3Bi. The adsorption energy and the d-band center were used as descriptors of catalytic activity and were compared to those of Pt and Pd. The descriptors suggest that Pd3Bi would have a better catalytic activity towards the ORR than pure Pd. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.