Fig. 10.

Experimental LSPR spectra of Cu(I)S nanorods. The spectra indicate that plasmonic excitation is the determinant for the NIR band of this material. The latter band is absent when the stoichiometry is (2:1) Cu:S in the as-synthesized sample. Exposure to oxygen leads to Cu vacancies that facilitate plasmonic excitations [146]. Reprinted by permission from Springer Nature: copyright 2011 Macmillan Publishers Ltd.