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

A series of GdF3:Yb(3+), Ln(3+) (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:Yb(3+), Ln(3+) nanoparticles may have potential applications in modifying the solar spectrum to enhance the efficiency of silicon solar cells.