Regulating surface composition of platinum-copper nanotubes for enhanced hydrogen evolution reaction in all pH values

Regulating catalyst composition is one of the efficient approaches to boost intrinsic activity of electrocatalysts for water splitting. Herein, four different hollow porous platinum-copper (PtCu) nanotubes (NTs) with controllable compositions were precisely fabricated by a facile wet-chemistry method. Importantly, Pt₅Cu₂ NTs display the best hydrogen evolution reaction (HER) performance in all pH conditions compared to other samples, which just require overpotentials of 34 ± 2, 32 ± 2, and 284 ± 2 mV at 10 mA cm^-2 in basic, acidic, and neutral solutions, respectively. Moreover, Pt₅Cu₂ NTs also exhibit outstanding stability and corrosion resistance in all pH ranges. Then, mechanism analysis reveals that the electronic structure of Pt sites is regulated by changing the ratio of Pt and Cu, which directly optimizes the binding energy of reaction intermediates and promotes electron transfer during the HER process. In addition, a porous nanotube structure with countless nanoparticles on the surface provides a large number of active sites, enhancing the adsorption/desorption of reactants. This work emphasizes the importance of catalyst composition and provides a highly active potential HER catalyst for practical hydrogen production.