The development of cost-effective catalysts for hydrogen evolution reaction (HER) and hydrogen oxidation reaction (HOR) is the key to realizing alkaline fuel cells and water electrolytic cells applications. Early reports have shown that surface modification of Pt-based catalysts with highly oxygenophilic metals can significantly enhance their HOR/HER activity. Here, we successfully synthesized uniform trimetallic PdPtNi hollow nanocages (PdPtNi HNCs) with excellent HER and HOR activity under alkaline media via hydrothermal deposition of oxygenophilic Ni on PdPt HNCs. Moreover, the PdPtNi HNCs exhibit superior HER/HOR durability and excellent CO-tolerance in HOR, compared with commercial Pt/C catalyst. The theoretical calculations confirm that the introduced Ni enriched the electronic and balanced the interactions of the adsorbed intermediates (OH_ad and H_ad) on the catalyst’s surface, thus promoting the HER and HOR activity. This work provides a promising approach for designing and synthesizing bifunctional and highly efficient catalysts.

Modulating Pt surfaces through the introduction of lattice distortion emerges as immensely effective strategy that enhances the kinetics of alkaline hydrogen evolution and oxidation processes. In this study, we fabricated lattice-distorted Pt wrinkled nanoparticles (LD-Pt WNPs) for efficient hydrogen electrocatalysis. The LD-Pt WNPs not only outperform the Pt/C benchmark in hydrogen oxidation reaction, achieving an excellent mass-specific current of 968.5 mA·mg_Pt⁻¹ (9 times that of Pt/C), but also demonstrate outstanding hydrogen evolution reaction activity with a small overpotential of 58.0 mV. Comprehensive experiments and density functional theory calculations reveal that lattice defects introduce an abundance of unsaturated coordination atoms while modifying the d-band center of Pt. This dual effect optimizes the binding strength of crucial H and OH intermediates, leading to a significant reduction in the energy barrier of the reaction bottleneck, commonly known as the Volmer step. This work unveils a fresh viewpoint on projecting and developing high efficiency electrocatalysts through defect engineering.