Template synthesis of low-density gold foams: Density, microstructure and compressive strength

High Z metallic foams with low density are required in high energy-density physical experiments. In this study, cylindrical Au foams with relative density as low as 5.6% were synthesized from a templating approach. Microspherical polystyrene (PS) was employed as the sacrificial template and aqueous solution of HAuCl4 as gold source. Au nanoparticles were successfully coated onto the surface of PS template from a two-step deposition process. Cylindrical PS/Au monoliths were formed by filter-casting of the Au coated PS beads. PS template was completely removed and self-supported Au foams were produced after drying, demolding and calcination. The monolithic Au foams demonstrate density as low as 1.08 g/cm3 and compressive strength as high as 3.2 Mpa.