Synthesis And Functionalization Of Rare Earth Fluoride Nanomaterials

(1)α-NaYF₄:Yb,Tm nanomaterials with spherical,red bean and strip shapes;meanwhileβ-NaYF₄:Yb,Tm spherical nanoparticles with a particle size of 62 nm were synthesized by controlling the solvent ratio and reaction time.Combined withβ-NaYF₄:Yb,Tm nanospheres showed strong upconversion luminescence,which indicated that it was more suitable for subsequent functionalization studies.（2）Theβ-NaYF₄:Yb,Tm synthesized in the above step was used as the precursor,Green light emitting NaYF₄:Yb,Tm@m Si O₂-PEG nanospheres with surface pore size of 3.06 nm and particle size of 92 nm were prepared.NaYF₄:Yb,Tm@m Si O₂-PEG,as drug delivery carriers,have good biocompatibility;the loading rate of water-soluble anti-cancer drug doxorubicin（DOX）is up to 89.6%,and can achieve p H response release,with sustained release effect;The loading rate of non-water soluble anti-cancer drug curcumin（Cur）is 70.0%,and it can be released Cur quickly;So it could be used in collaboration with biological imaging and drug delivery.（3）NaYF₄:Yb,Ho@NaYF₄:Yb,Nd-PEG nanoparticles were designed and synthesized.The core-shell structure enhanced the upconversion luminescence;Nd³⁺and Yb³⁺co-doping regulated the excitation wavelength to 808 nm with less optical damage.The nanospheres have good biocompatibility,small size,green light and surface pore size of 3.03 nm;The loading rate of DOX was up to 95.6%,and p H response release could be achieved;The loading rate of Cur is 61.0%,and can be rapidly release Cur;So it could be used in collaboration with biological imaging and drug delivery.（4）Based on the electrostatic attraction of the water phase,NaYF₄:Yb,Er@NaYF₄:Yb,Nd/H-g-C₃N₄ composite photocatalyst was prepared.NaYF₄:Yb,Er@NaYF₄:Yb,Nd can cooperatively absorb light at 808 nm and 980 nm to emit UV-visible light,which triggers the photocatalytic process of H-g-C₃N₄,So it increases the utilization rate of sunlight.The photocatalytic degradation rate of tetracycline hydrochloride in water was 71.8%when simulated sunlight irradiated for 130 min,and 44.9%when near infrared light irradiated for 240 min.The degradation rate of Rhodamine B in water was 91.2%under simulated sunlight irradiation for 30 min,1.5 times that of H-g-C₃N₄ alone;and 61.2%under near-infrared light irradiation for 3 h.