Tuning the LSPR in copper chalcogenide nanoparticles by cation intercalation, cation exchange and metal growth

Abstract

Localized surface plasmon resonances (LSPRs) of degenerately doped copper chalcogenide nanoparticles (NPs) (Cu2−xSe berzelianite and Cu1.1S covellite) have been modified applying different methods. The comparison of the cation exchange (Cu2−xSe) and intercalation (Cu1.1S) of Ag(I) and Cu(I) has shown that Ag(I) causes a non reversible, air stable shift of the LSPR. This was compared to the influence of Au(I) cation exchange into Cu1.1S platelets under the formation of Cu1.1S–Au2S mixed nanoplatelets. Furthermore, we show the growth of Au domains on Cu2−xSe, and discuss the interaction of the two plasmonic parts of the obtained dual plasmonic Cu2−xSe–Au hybrid particles.