Band structure and near infrared quantum cutting investigation of GdF3:Yb3+, Ln3+ (Ln = Ho, Tm, Er, Pr, Tb) nanoparticles

Abstract

A series of GdF₃:Yb³⁺, Ln³⁺ (Ln = Ho, Tm, Er, Pr, Tb) nanoparticles were prepared by a simple and green hydrothermal method without any additives, which exhibited an ellipse-like shape with a diameter of 63 nm and a length of 101 nm on average. To prove the existence (or not) of near infrared quantum cutting for various lanthanide ion couples (Yb/Ho; Yb/Tm; Yb/Er; Yb/Pr; Yb/Tb) in one host lattice (GdF₃), the measured luminescence spectra and decay lifetimes of these samples were analysed. Furthermore, the band structures and densities of state of GdF₃ were also studied with the help of first-principles calculations, and the direct band gap of GdF₃ was estimated to be 7.443 eV wide. Based on this, detailed processes and possible mechanisms of the luminescence phenomena are discussed. GdF₃:Yb³⁺, Ln³⁺ nanoparticles may have potential applications in modifying the solar spectrum to enhance the efficiency of silicon solar cells.