Controlling plasmon–luminescence interactions in ordered architectures by deposition of gold nanorods onto rare-earth based particles

Luminescence modulation by plasmonic effects is highly dependent on the concentration and distance of the emitting centers, as well as on the dielectric constant of the medium. These effects are normally associated with localized surface plasmon resonance (LSPR) induced by gold nanorods (AuNRs). We systematically investigated the interaction between Er³⁺ emissions and plasmon-modulated optical fields by deposition of AuNRs onto different luminescent submicrometric particles based on Y³⁺/Yb³⁺/Er³⁺ cations, namely vanadates (V), fluorides/vanadates (FV), and molybdates/vanadates (MV) under 980 nm excitation. Direct anchoring using thioglycolate as a molecular linker enabled controlled attachment and distance2 of AuNRs via RE³⁺–COO⁻ and Au–S interactions. This approach allowed precise and reproducible nanoparticle loading (5 or 10% wt. of AuNRs) over the luminescent solids. These findings provide new insights into plasmon– lanthanide interactions and highlight the role of the dielectric environment as a key parameter for tuning optical responses in hybrid nanostructures.