Synthesis of Single-Crystalline Ag Microcubes up to 5.0 mu m by the Multistage Seed Growth Method

Abstract

Here, we introduce a multistage seed growth method that can grow the size of single-crystalline Ag cubes from hundreds of nanometers up to 5.0 mu m. In this method, seed synthesis and further growth are conducted continuously in the same batch, which increases the achievable size of cubes by preventing cubes from mechanical damage and chemical degradation. With optimized conditions for molecular weight and concentration of a capping agent, poly(vinylpyrrolidone) (PVP), 5.0 mu m Ag microcubes are successfully synthesized from 390 nm Ag nanocubes by five stages of seed growth. We also prepare AuAg alloyed boxes from synthesized nanocubes and microcubes by a galvanic replacement using an aqueous HAuCl4 solution and describe their shape change according to the concentration of HAuCl4. We provide a reliable method to synthesize uniform nano to microscale cubes and boxes useful for controlled drug delivery, catalysis, biolistic particle delivery, and impact-induced mechanical strengthening.