Achieving self-supported nanoporous Cu catalysts with good conductivity for hydrogen evolution via dealloying amorphous ribbons

Abstract

With the development of energy conservation, fabricating hydrogen evolution reaction (HER) catalysts with high catalytic activity and long-term stability is a challenging research area. Herein, the nanoporous Cu-based self-supporting catalysts D-Au0, D-Au1, and D-Au3 are fabricated via dealloying of the amorphous CuTiAu ribbons by adding 0, 1, and 3 at% Au, respectively. The introduction of Au increases the glass forming ability of CuTi alloys and refines the pore size of the as-dealloyed ribbons; meanwhile, the annealed crystalline ribbons exhibit drastically weaker HER performance and lower ductility than their as-spun counterparts. Furthermore, the D-Au3 ribbon exhibits a low overpotential η₁₀ (191.2 mV), a high electrochemical surface area (263.8 cm²), and a high turnover frequency (0.003 s⁻¹) at 100 mV. Additionally, D-Au1 has a high stability at a constant current density of 10 mA cm⁻² for 140 h due to not only the partially retained nanoporous structure but also the Cu/CuO Mott–Schottky junction, which enhances H* adsorption. Compared with other self-supporting catalysts, the nanoporous Cu-based catalysts exhibit a moderate performance and low cost while maintaining excellent conductivity and ductility. This work may provide meaningful insights into the design of amorphous materials, the preparation of bimetallic HER catalysts, and their promising application potential.