Ultrathin Porous WPdH Nanosheet Assemblies for Efficient Alkaline Oxygen Reduction

The design of active and durable cathodic electrocatalysts is critical for practical fuel cell applications. Although Pd is a promising candidate to replace Pt for oxygen reduction reaction (ORR), it usually suffers from lower activity. Here, a two-step method is reported to synthesize tungsten–palladium bimetallic hydrides with a porous nanosheet assembly structure (WPd–H NSAs) as high-performance ORR electrocatalysts. The introduction of H atoms to Pd and curved porous nanosheet structures can induce the strain and electronic effects, leading to the weaker binding energy of O on Pd. The WPd–H NSAs show a superior ORR activity of 1.51 mA μgPd–1, 10.43 times that of Pt/C. This hydrogenation approach would open the way to design high-efficiency palladium-based nanomaterials with controlled morphology for ORR.