The Physics Society of Iran Iranian Journal of Physics Research 1682-6957 20 4 2021 02 19 Visible and near infrared upconversion emission from Tm3+, Yb3+ ‎doped SrF2 nanoparticles Visible and near infrared upconversion emission from Tm3+, Yb3+ ‎doped SrF2 nanoparticles 591 597 1651 10.47176/ijpr.20.4.37861 FA M Ghorashi Institute for Nanoscience and Nanotechnology, Sharif University of Technology, Tehran, Iran H R Madaah-Hosseini Department of Materials Science and Engineering, Sharif University of Technology, Tehran, Iran E Mohajerani Laser and Plasma Research Institute, Shahid Beheshti University, Tehran, Iran Journal Article 2019 05 19 Tm³⁺, Yb³⁺-codoped SrF₂ nanoparticles were synthesized through a facile hydrothermal ‎technique. Citrate ions were introduced as the capping agent into the reaction. Upconversion ‎nanoparticles were characterized by field emission scanning electron microscopy (FESEM), ‎Energy dispersive x-ray spectroscopy (EDS), x-ray diffraction (XRD), Dynamic light scattering ‎‎(DLS), Zeta potential, Fourier transform Infrared spectroscopy (Ft-IR), and the 980 nm laser induced ‎photoluminescence spectroscopy. Rare-earth ions (Na⁺), which are the cations of citrate salts, ‎are incorporated into the structure to  act as charge compensators. Upconversion emission in the ‎visible and NIR region was observed by the 980 nm irradiation. Nanoparticles with a narrow size ‎distribution and a uniform morphology were directly dispersible in water, forming a quite transparent ‎suspension. Nanoparticles size was approximately 10 nm. High penetration of the  Near-Infrared light into ‎the body tissue makes these nanoparticles appropriate for tumor targeting in the deeper tissues for ‎the purpose of bioimaging and photodynamic therapy‎.   Tm³⁺, Yb³⁺-codoped SrF₂ nanoparticles were synthesized through a facile hydrothermal ‎technique. Citrate ions were introduced as the capping agent into the reaction. Upconversion ‎nanoparticles were characterized by field emission scanning electron microscopy (FESEM), ‎Energy dispersive x-ray spectroscopy (EDS), x-ray diffraction (XRD), Dynamic light scattering ‎‎(DLS), Zeta potential, Fourier transform Infrared spectroscopy (Ft-IR), and the 980 nm laser induced ‎photoluminescence spectroscopy. Rare-earth ions (Na⁺), which are the cations of citrate salts, ‎are incorporated into the structure to  act as charge compensators. Upconversion emission in the ‎visible and NIR region was observed by the 980 nm irradiation. Nanoparticles with a narrow size ‎distribution and a uniform morphology were directly dispersible in water, forming a quite transparent ‎suspension. Nanoparticles size was approximately 10 nm. High penetration of the  Near-Infrared light into ‎the body tissue makes these nanoparticles appropriate for tumor targeting in the deeper tissues for ‎the purpose of bioimaging and photodynamic therapy‎.   https://ijpr.iut.ac.ir/article_1651_be3e9d3f7d70537357c67bb3f4086846.pdf