Component-dependent electrocatalytic activity of PdCu bimetallic nanoparticles for hydrogen evolution reaction

The development of high efficient electrocatalysts in water electrolysis is of great importance for sustainable hydrogen production. Herein, monodispersed bimetallic PdxCu100-x nanoparticles with average size about 4.7 nm are prepared by a one-pot method in oleylamine medium. Electrochemical measurements toward hydrogen evolution reaction (HER) indicate that both the activity and stability of carbon black loaded PdxCu100-x nanoparticles (PdxCu100-x/C) are highly dependent on the Pd/Cu atomic ratios. Among these electrocatalysts, Pd71Cu29/C exhibits the best electrocatalytic activity in terms of onset potential (75 mV vs. RHE), exchange current density (0.38 mA cm−2) and Tafel slope (48 mV dec−1) in 0.1 M H2SO4 among these nanoparticles. It is found that the activity toward HER of Pd71Cu29/C is better than that of commercial Pd/C and most of Pd-based electrocatalysts ever reported before. Moreover, Pd71Cu29/C shows superior catalytic stability to the commercial Pt/C. The superior HER activities and high durability (after 1000 CV cycles) of Pd71Cu29/C should be attributed to small size, the synergy effect between Cu and Pd. This work provides a facile strategy to develop the effective and stable Pt-free electrocatalyst for hydrogen generation.