Preparation of Mechanically Robust, Macroscopic Low-Density Gold Foams by Highly Efficient Electroless Gold Plating - Abstract
Mechanically robust, macroscopic-sized low-density gold foams with unique morphology of hollow gold shells were prepared by the synthesis of gold-coated polystyrene coreshell particles followed by thermal removal of the polymer core. Here, we reported a simple, highly efficient electroless gold plating procedure to form ultrathin, conformal gold
coatings on the surface of polystyrene particles. A modified, scalable casting approach to form uniform, large monoliths (up to 1 cm diameter) and a baking condition to minimize
undesirable densification of final foams were also developed. To demonstrate the mechanical stability and integrity of the Au foams, a representative monolithic sample (~0.9 g/
cm3
) was successfully cut and shaped into a gold foam “washer” by a series of precision machining and processing. A depth-sensing indentation test (nanoindentation) as well as
characterizations on other useful properties such as surface areas and electrical conductivity of the Au foams were carried out to understand the mechanical behavior and potential
applicability.