Figure 4.

TEM images of different types of gold nanoparticles: (a) gold nanospheres; reprinted with permission from [30]; copyright (2005) American Chemical Society; (b) gold nanorods; reprinted with permission from [31]; copyright (2013) American Chemical Society; (c) gold nanocages; reprinted with permission from [31]; (d) gold nanohexapods; reprinted with permission from [31]; (e) gold bipyramids; reprinted with permission from [32]; copyright (2005) American Chemical Society; (f) “nanorice” (gold-coated Fe₂O₃ nanorods); reprinted with permission from [33]; copyright (2006) American Chemical Society; (g) SiO₂/Au nanoshells (the inset shows a hollow nanoshell); reprinted with permission from [29]; copyright (2010) Elsevier; (h) nanobowls with bottom cores; reprinted with permission from [34]; copyright (2009) American Chemical Society; (i) spiky SiO₂/Au nanoshells (reprinted with permission from [35]; copyright (2010) American Chemical Society; the inset shows a gold nanostar); reprinted with permission from [36]; copyright (2006) American Chemical Society.