Effect of Nonradiative Transitions on the Upconversion Properties of YVO4:Yb, Er Nanoparticles

The results from a comparative analysis of the emission spectra of upconversion YVO4:Yb, Er nanoparticles synthesized in sizes ranging from 10 nm to 1 μm are used to discuss the contribution from high-energy oscillators on the surfaces of nanoparticles to the nonradiative energy transfer between Er3+ ion levels, and to the formation of the red emission band at 660 nm.