Figure 18.

(A) Illustration of the reduction and growth process of Ag on the inner and outer surfaces of porous gold nanoshell (AuNS) with increasing amounts of Ag⁺ in the surrounding medium. STEM elemental mapping (Ag, Au, and overlay) of AuNS obtained after adding Ag⁺: (B) [Ag⁺] = 0.16 mM and the corresponding elemental profile along the white hatched line and (C) [Ag⁺] = 0.32 mM and the corresponding elemental profile along the white hatched line. The black ellipse in (C) highlights the reduction and growth of Ag at the external surface once the inner volume is completely filled. Adapted from [163]. Copyright (2019), American Chemical Society.