Fig. 8

The optical and SEM images of MPA-coated Si wafer before and after treating with Au seed-mediated enhancement. THPC-Au seeds could be observed in SEM image of THPC-Au seed-treated Si wafer, but they were too small to see clearly. After THPC-Au seed-treated Si wafer treated with Au⁺-CTAB complexes, many Au NPs with different sizes produced on the surfaces of Si wafer. These results indicated the growth of Au NPs was certainly from Au seeds. Scale bars in all SEM images are 200 nm