Synthesis of high-quality garnet-type Gd3Sc2Al3O12:Ce3+ nanocrystals

The synthesis of garnet-type Gd₃Sc₂A_l3O₁₂ (GSAG) nanoparticles doped with Ce³⁺ ions under solvothermal conditions in 1,4-butanediol is reported in this work. X-ray diffraction with LeBail fitting, Electron microscopy images and photoluminescence spectra were used to characterize the samples. A detailed Transmission Electron Microscopy study shows strong modification of particle morphology upon reaction temperature. Performing the reaction at high temperature and high pressure leads to a clear increase of the particle crystallinity and allows the formation of 100-nm sized nanocrystals with a small size dispersion (± 20 nm). The formation mechanism of these particles is through the self-orientation of primary crystalline grains. Yellow-orange luminescence of Ce³⁺-doped GSAG nanoparticles is observed upon 457-nm excitation. Photoluminescence intensity drastically increases when the particles are synthesized at high temperature, which is directly correlated to their crystal quality.