Femtosecond pulsed laser induced synthesis of ultrafine Y2O3: Pr, Yb nanoparticles with improved upconversion efficiency

Femtosecond-pulse laser-ablation-induced synthesis and improved emission properties of ultrafine Y2O3:Er3+, Yb3+ nanoparticles with reduced nonradiative relaxation

“…Preparation of Y 2 O 3 :Er 3þ , Yb 3þ nanoparticles using femtosecond pulsed laser ablation Y 2 O 3 nanoparticles doped with 1 mol% Er 3þ and 0 or 5 mol% Yb 3þ were prepared using a laser ablation method, as previously reported [24]. Briefly, Y 2 O 3 , Er 2 O 3 , and Yb 2 O 3 powders with 99.99% purity were mixed and pressed into pellets using a pressure of 10 MPa that was applied for 90 s. These pellets were used as targets for a Ti:sapphire femtosecond laser beam (Spectra Physics) operated at 800 nm and with a pulse width of 120 fs, repetition rate of 1 kHz, pulse energy of 0.8 mJ/pulse, and a diameter of 0.2 mm at the pellet surface.…”

“…As the main sources of these highenergy phonon groups are the initial materials used during the preparation of UC nanomaterials, avoiding contamination during the preparation process is an important criterion for improving the UC efficiency and performance of the resultant nanomaterials. Efficiency improvements in visible UC emission have been realized in Pr 3þ -and Yb 3þ -doped Y 2 O 3 nanoparticles prepared using the femtosecond-pulsed laser ablation method [24]. As this method helps prevent possible chemical contamination and, therefore, reduces high-energy-phonon-assisted nonradiative relaxation, these nanoparticles exhibit high UC emission intensity.…”

Infrared to infrared upconversion emission in Pr3+/Yb3+ co-doped La2O3 and La(OH)3 nano-phosphors: A comparative study

“…They give efficient up and downconversion emissions due to 4f-4f and 4f5d-4f electronic transitions. Most of the earlier work based on upconversion process report a conversion of infrared light to visible or visible to ultraviolet (UV) light [12][13][14][15][16][17][18]. Only in few reports the upconversion in infrared to infrared regions have been observed [12,16,19].…”

Upconversion emission from amorphous Y2O3:Tm3+, Yb3+ prepared by nanosecond pulsed laser irradiation

“…In a recent work, ultrafine Y 2 O 3 :Pr 3+ , Yb 3+ nanoparticles were prepared by femtosecond pulsed laser irradiation [15]. Because the method can avoid possible chemical contamination, these nanoparticles showed higher UC efficiency, compared with nanoparticles synthesized by typical sol-gel method.…”