Dealloying behavior of amorphous binary Ti–Cu alloys in hydrofluoric acid solutions at various temperatures

•The dealloying process has a temperature dependency.•The surface diffusivity decreases drastically with a decrease of temperatures.•The dealloying process follows Arrhenius law.•The activation energy for amorphous binary Ti–Cu alloys is 40.3–78.1kJmol−1. A nanoporous copper structure was fabricated from amorphous binary TixCu100−x (x=40, 50 and 60at.%) alloys in hydrofluoric acid solutions under a free corrosion condition. A bi-continuous nanoporous structure has a pore size of 25–75nm and a ligament size of 46–79nm in 0.03M HF solution. In 0.13M HF solution, a pore size of 85–380nm and a ligament size of 80–338nm were obtained. The dealloying process is thermal-activated and obeys the Arrhenius law. The surface diffusivity decreases with temperature and concentrations of dealloying solutions. The values of the activation energy of copper adatoms are estimated to be 40.3–78.1kJmol−1, which depend not only on the alloy composition but also on the dealloying electrolyte composition.