Surfactant-free aqueous synthesis of novel Ba3Gd2F12:Ln3+ nanocrystals with luminescence properties

Abstract

A novel xBaF₂–yGdF₃ solid solution of Ba₃Gd₂F₁₂:Ln³⁺ (Ln = Eu, Dy, Tb, Ce, Er, Tm, and Yb) nanocrystals with multicolor emissions has been prepared via a surfactant-free aqueous hydrothermal route for the first time. The as-prepared nanocrystals are uniform single crystals with nanocube shape and average size of about 23 nm. We have experimentally verified that the aqueous wet chemical synthetic route is necessary and feasible for the fabrication of complex inorganic nanocrystals with the target phase. As a proof-of-concept experiment, multicolor luminescence is explored by downshifting (Eu, Dy, Tb, Ce), up-conversion (Yb/Er, Yb/Tm), and energy transfer processes (Ce → Tb), which indicate that Ba₃Gd₂F₁₂ is a highly efficient luminescence host, which shows great promise as a phosphor and ideal multi-model bio-probe.