Phase transition from hexagonal LnF3 (Ln = La, Ce, Pr) to cubic Ln0.8M0.2F2.8 (M = Ca, Sr, Ba) nanocrystals with enhanced upconversion induced by alkaline-earth doping†
Abstract
Complete phase transition from hexagonal LnF3 (Ln3+ = La3+, Ce3+, Pr3+) to monodisperse ultrasmall (∼7 nm) cubic Ln0.8M0.2F2.8 (M2+ = Ca2+, Sr2+, Ba2+) disordered solid solution nanocubes was successfully achieved through alkaline-earth doping, which induced great intensification of the near-infrared to visible upconversion emissions of the optically active rare earth ions.