Figure 7

The FESEM pictures of Ag-Au hetero-nanostructures and flower-like Ag nanostructures as a function of time reaction with H₂O₂. (a–c) Are the FESEM pictures of the flower-like Ag-Au hetero-nanostructures after etching for 5 h, 10 h and 24 h by H₂O₂, respectively. (d–f) Are the FESEM pictures of the flower-like Ag nanostructures after etching for 5 h, 10 h and 24 h by H₂O₂, respectively.