In Situ Growth of Ag Nanodots Decorated Cu2O Porous Nanobelts Networks on Copper Foam for Efficient HER Electrocatalysis

Abstract Developing earth‐abundant electrocatalysts for high‐efficiency hydrogen evolution reaction (HER) has become one of the leading research frontiers in energy conversion. Here, the design and in situ growth of Ag nanodots decorated Cu 2 O porous nanobelts networks on Cu foam (denoted as Ag@Cu 2 O/CF) are carried out via a simple one‐pot solution strategy at room temperature. Serving as self‐supporting electrocatalysts, Ag@Cu 2 O porous nanobelts provide plentiful active sites, and the 3D hybrid foams provide fast transportation for electrolyte and short diffusion path for newly formed H 2 bubbles, which result in excellent electrocatalytic HER activity and long‐term stability. Owing to the synergistic effect between Ag nanodots and Cu 2 O porous nanobelts and CF, the hybrid electrocatalyst exhibits a low Tafel slope of 58 mV dec −1 , a small overpotential of 108 mV at 10 mA cm −2 , and high durability for more than 20 h at a potential of 200 mV for HER in 1.0 mol L −1 KOH solution.