Preparation of self-supported nanoporous gold film

The free-standing nanoporous gold film was synthesized by free corrosion dealloying in the increasing HNO₃ solution. Au-Ag precursors was preparated by alloying the Au and Ag film of the magnetron sputtered. Micro-structure and composition of the sample before and after dealloying were characterized with scanning electron microscope and energy dispersive analysis of X-ray. The results indicated that the Au-Ag alloy precursors were obtained by 400 ℃ heat-treatment for 36 h. The increasing HNO₃ solution prevented the surface to crack. The self-supported nanoporous gold with size up to 15mm × 15 mm, thickness of 400-500 nm, ligament size of 40-40 nm, porosity of 56% were obtained. (authors)