Ultrafine Ag Nanoparticles as Active Catalyst for Electrocatalytic Hydrogen Production

Ag nanoparticles with different sizes were produced by laser ablation in liquid (PLAL) through tuning laser energy. As the catalyst for hydrogen evolution reaction (HER) in acidic medium, Ag nanoparticles show strong size‐dependent activity, and the smallest Ag nanoparticles with average size of 3 nm display a low overpotential of 96 mV at 10 mA cm−2 and Tafel slope of 76.10 mV dec−1, being superior to Ag foil and commercial Ag powder. The excellent performance is attributed to the large exposed surface, low coordination number, moderate hydrogen adsorption energy, and low charge transfer resistance. Electrocatalysis: An eco‐friendly technique, laser ablation in liquid, to prepare Ag nanocatalysts with ultrafine size (approx. 3 nm) and clean surface is presented. The Ag nanoparticles displays an overpotential of 96 mV at 10 mA cm−2 and Tafel slope of 76.10 mV dec−1 for HER in acid medium, overwhelming the commercial Ag powder. Experimental and theoretical investigations reveal that the excellent catalytic activity arises from large exposed surface, abundant active sites, moderate adsorption energy for hydrogen, and low charge transfer resistance.