Fig. 7. The increasing addition of (a) 0.20, (b) 0.40, (c) 0.60 and (d) 0.80 mM HBr to the precursor reaction mixture clearly influences the formation as well as the self-organization of anisotropic gold nanostructures, as prominently revealed by the optical spectra and their corresponding TEM images (scale bar 200 nm with inset scale bar 100 nm). Reprinted with permission from ref. 89. Copyright © 2014 Royal Society of Chemistry.