Localized Surface plasmon in semiconducting in MoS2 nanoparticles

Lena Yadgarov, Weizmann Institute of Science, Rehovot, Israel
Bojana Visic, Weizmann Institute of Science, Rehovot, Israel
Rita Rosentsveig, Weizmann Institute of Science, Rehovot, Israel
Reshef Tenne, Weizmann Institute of Science, Rehovot, Israel

The optical and electronic properties of suspensions of inorganic nanoparticles of WS₂/MoS₂ are studied through light absorption, zeta potential and transient absorption measurements. The total extinction measurements show that, in addition to excitonic peaks and the indirect bandgap transition, a new peak is observed at 650-800 nm. This spectral peak has not been reported previously for WS2/MoS₂. Comparison of the total extinction and decoupled absorption spectrum indicates that this peak largely originates from scattering. Furthermore, the dependence of this peak on nanoparticle size, shape, and surface charge, as well as solvent refractive index, suggest that this transition arises from a plasmon resonance.