Atomic scale enhancement of metal-support interactions between Pt and ZrC for highly stable electrocatalysts

To further obtain high catalytic activity and durability of Pt catalysts for oxygen reduction reaction (ORR), we synthesized a robust Pt-on-ZrC nanocomposite catalyst by taking advantage of atomic layer deposition (ALD) to improve the strong metal-support interactions at the atomic level. X-ray absorption near edge structures (XANES) results show that ALD-Pt/ZrC catalysts show noticeable change in the electronic structure of Pt due to strong interactions with the ZrC support. Using electrochemical cycling to test durability, we found the ALD-Pt/ZrC nanocomposites to be roughly 5-fold and 3-fold more stable than commercial Pt/C and CW-Pt/ZrC (synthesized by a conventional chemical reduction method), respectively. The ALD-Pt/ZrC nanocomposite showed a mass activity of 0.122 A mg(Pt)(-1) at 0.9 V (vs. RHE); much higher than those for Pt/C and CW-Pt/ZrC catalysts (0.074 and 0.041 A mg(Pt)(-1), respectively). After durability test, our novel catalyst also exhibited ORR activity 9 times greater than Pt/C. This approach, using ALD to grow the Pt catalyst directly, resulting in strong interactions, will aid the design of new active and stable catalysts for ORR or other chemical reactions.