Doped metal oxide (MO) nanocrystals (NCs) are well-known
for the
localized surface plasmon resonance in the infrared range generated
by free electrons in the conduction band of the material. Owing to
the intimate connection between plasmonic features and the NC’s
carrier density profile, proper modeling can unveil the underlying
electronic structure. The carrier density profile in MO NCs is characterized
by the presence of an electronically depleted layer as a result of
the Fermi level pinning at the surface of the NC. Moreover, the carrier
profile can be spatially engineered by tuning the dopant concentrations
in core–shell architectures, generating a rich plethora of
plasmonic features. In this work, we systematically studied the influence
of the simulation parameters used for optical modeling of representative
experimental absorption spectra by implementing multilayer models.
We highlight in particular the importance of minimizing the fit parameters
by support of experimental results and the importance of interparameter
relationships. We show that, in all cases investigated, the depletion
layer is fundamental to correctly describe the continuous spectra
evolution. We foresee that this multilayer model can be used to design
the optoelectronic properties of core–shell systems in the
framework of energy band and depletion layer engineering.