Cubic KLu3F10 nanocrystals: Mn2+ dopant-controlled synthesis and upconversion luminescence

Abstract

Cubic KLu₃F₁₀ nanocrystals have been fabricated by doping Mn²⁺ ions via a liquid–solid solution (LSS) hydrothermal method. With an increase in the Mn²⁺ level, a phase transformation from orthorhombic KLu₂F₇ to cubic KLu₃F₁₀ associated with evolution of the particle morphologies and sizes is evident. The phase transformation mechanism based on doping with Mn²⁺ ions was studied via a series of time-controlled experiments and the enhancement of the intensity of upconversion luminescence (UCL) via doping with Mn²⁺ ions is discussed in detail. In addition, under 980 nm excitation, the UCL properties of Er³⁺/Tm³⁺/Ho³⁺-doped KLu₃F₁₀:Yb³⁺ upconversion nanoparticles (UCNPs) have been investigated and a possible UCL mechanism has been discussed. It has been demonstrated that cubic KLu₃F₁₀ is an excellent host for upconversion luminescence.