Energy transfer from SnO₂ host to Eu³⁺ ions and photoluminescence quenching of SnO₂:Eu³⁺ nanocrystals

SnO2:Eu3+ nanoparticles were prepared by hydrothermal method. The crystal structure, size, phase composition, and morphology of the materials were investigated by X-ray diffraction measurements, scanning electron microscopy, Raman scattering spectroscopy. The absorption and optical properties of the materials were studied by UV-vis absorption spectroscopy, photoluminescence excitation spectroscopy, and photoluminescence spectroscopy. Results showed that the SnO2:Eu3+ nanoparticles had a tetragonal rutile crystal structure and were about 5-15 nm in size. They were also smaller than pure SnO2. When doping Eu3+ into SnO2, the crystal size of SnO2:Eu3+ nanoparticles decreased, the defects increased, and the crystallinity decreased. The SnO2:Eu3+ samples emitted in the emission region related to the SnO2 host and the emission peaks of the Eu3+ ion impurity. Moreover, energy transfer occurred from the SnO2 host to Eu3+ ions. The photoluminescence spectra of SnO2:Eu3+ nanoparticles with indirect and direct excitation were further studied. The influences of Eu3+ concentration on the structure, morphology, and optical properties of SnO2:Eu3+ nanoparticles were investigated in detail.