A green approach for self-assembly of Ag-Au nanoparticles into 3-D arrays

摘要

In this investigation, we report the formation of new 3-D aggregates consisting of Ag-Au nanoparticles obtained in aqueous solution by a facile method using Aloysia triphylla plant extract as a reducing and stabilizing agent. SEM and EDS analysis reveal that the dimensions of 3-D arrays are estimated to be about 2.5 mu m wide, 0.5 mu m thick, and 2 mu m long. The 3-D geometric aggregates have strong microstructures that are similar to those of ordinary crystalline materials. The microstructures are close-packed with straight edges and facets but do not have grain boundaries. HRTEM images indicate that the 3-D arrays are a consequence of the nanoparticles aggregation inside an organic matrix and the presence of Au forming the BNPs.