Nanoporous gold with tunable morphology by electrochemical dealloying of ordered Cu 3 Au in low concentration acids

Abstract Nanoporous gold has been produced by the electrochemical dealloying of ordered Cu 3 Au ribbons with a thickness of 50 μm ribbons. Potentiostatic and Galvanostatical methods were used to control the dealloying process in 0.2M HNO 3 , 0.2 M HClO 4 and 0.2 M H 2 SO 4 solutions, respectively. The average ligament sizes of nanoporous gold by Potentiostatic method in sulfuric acid and nitric acid solutions, were 10±5 nm and 22±7 nm, respectively. The nanopores etched by perchloric acid had a typical two kinds of nanoporous structures l30 ± 10 nm and 42 ± 10 nm.The results indicate that the dealloying provides a convenient route to convert Cu₃Au into functional catalytic materials. By finely tuning the dealloying conditions applied current density, the porosity, ligament size, residual Cu content, and surface chemical state of the product can be tailored at the nanoscale, enabling systematic optimization of the catalytic performance.