(490f) Gold Nanoplate-Based 3D Hierarchical Microparticles with High SERS Enhancement

Formation of intended nano- and micro-structures with regular building blocks has attracted much attention due to their potential applications in the fields of optic, electronic and catalysis. Herein, we report a novel strategy to spontaneously grow individual Au nanoplates into three-dimensional (3D) hierarchical cabbage-like microparticles (CLMPs). By reducing gold precursor to gold atoms, N-(3-amidino)-aniline (NAAN) itself was oxidized to form poly (N-(3-amidino)-aniline) (PNAAN), which specifically binds on Au (111) facet as capping agent and led to the formation of gold nanoplates. Due to the incomplete coverage of Au (111) facet, new gold nanoplate growth sites were spontaneously generated from the crystal plane of existing Au nanoplates for the growth of other nanoplates. This process continued until the nanoplate density reached its maximum range, eventually resulting in CLMPs with well-controlled structures. It opens a new avenue to utilize the imperfection during nanoparticle (NP) growth for the construction of microstructures. The individual CLMP shows excellent surface-enhance Raman scattering (SERS) performance with high enhancement factor (EF) and good reproducibility as it integrates the SERS enhancement effects of individual Au nanoplate and the nanogaps formed by the uniform and hierarchical structures.