As the growth time increased from 24 to 48 h, the fitted Lpeak attributed to the longitudinal LSPR band shifts from 853to 995 nm, which corresponds to the increase in the length ofthe branches as shown in the corresponding TEM images(Figure 1a and 1b) because the SPR effect is strongly sizedependent. The fitted T peaks at 604 and 627 nm in Figure 2cand 2d represent the shifts in the positions of the transverseLSPR bands of the branches. Relatively broad shapes of T andL bands suggest various lengths of transverse and longitudinalaxes because the branch sizes are nonuniform. The T band isonly slightly red shifted by ∼23 nm, whereas the red shift of theL band is almost ∼150 nm when the synthesis time wasincreased from 24 to 48 h. This result suggests that theanisotropic growth of branches occurs preferably along thelongitudinal axes. According to the lightning rod effect, moreacute vertices yield a longer wavelength LSPR extinction
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