Sinter-Resistant Pd-P/C Electrocatalyst for Durable Oxygen Reduction.

Incorporating heteroatoms (X) into carbon-supported platinum group metal electrocatalysts to form M-X-C linkages is widely adopted to mitigate particle sintering. However, traditional methods that embed X within the carbon matrix typically yield a low density of X sites around each particle, thus affording limited stabilization. Here, we overcome this limitation by implanting X atoms directly on the supported particles, which enrich both the metal surface and the metal-support interface with X and thereby achieve comprehensive stabilization of the resulting M-X/C architecture. Using Pd-P/C as an example, we show both theoretically and experimentally that the surface P decoration not only creates an antidemetalization Pd-P surface but also fosters abundant interfacial C-P bonds, thereby conferring to excellent sintering resistance against both Ostwald ripening and particle migration. Pd-P/C exhibits outstanding catalytic durability for the oxygen reduction reaction (ORR), maintaining its activity and size distribution over 10,000 accelerated cycles even with ∼2 nm particles, substantially outperforming its Pd/P-C counterpart and the commercial Pd/C benchmark.