PtPd Atomic Layer Shelled PdCu Hollow Nanoparticles on Partially Unzipped Carbon Nanotubes for Breaking the Activity-Stability Trade-Off toward the Hydrogen Oxidation Reaction in Alkaline Media.

Developing highly active yet stable catalysts for the hydrogen oxidation reaction (HOR) in alkaline media remains a significant challenge. Herein, we designed a novel catalyst of atomic PtPd-layer shelled ultrasmall PdCu hollow nanoparticles (HPdCu NPs) on partially unzipped carbon nanotubes (PtPd@HPdCu/W-CNTs), which can achieve a high mass activity, 5 times that of the benchmark Pt/C, and show exceptional stability with negligible decay after 20,000 cycles of accelerated degradation test. The atomically thin PtPd shell serves as the primary active site for the HOR and a protective layer that prevents Cu leaching. Additionally, the HPdCu substrate not only tunes the adsorption properties of the PtPd layer but also prevents corrosive Pt from reaching the interface between NPs and the carbon support, thereby mitigating carbon corrosion. This work introduces a new strategy that leverages the distinct advantages of multiple components to address the challenges associated with slow kinetics and poor durability toward the HOR.