Preparation Of (Cay)F-2:Tm3+,Yb3+ Deposited Porous Tio2 Matrix With Highly Near-Infrared Light Photocatalytic Activity

Abstract Porous titanium dioxide (TiO2) matrix deposited with upconversion luminescence agent (CaY)F2:Tm3+,Yb3+ was sol–gel prepared using polymethyl methacrylate (PMMA) microspheres as sacrificing template and tetrabutyl titanate as TiO2 precursors. The resulted photocatalysts were subsequently characterized by X‐ray diffraction, scanning microscopy, transmission electron microscopy, X‐ray photoelectron spectroscopy, photoluminescence spectra (PL) etc. The photocatalytic activity and biocompatibility of TiO2/(CaY)F2:Tm3+,Yb3+ were evaluated by photocatalytic degradation of methyl orange (MO) and fibroblast cytotoxicity analysis, respectively. The results revealed that (CaY)F2:Tm3+,Yb3+ nanoparticles were well dispersed onto the pore walls of porous TiO2 matrix to generate a biocompatible composite. In addition, TiO2/(CaY)F2:Tm3+,Yb3+ was found to show excellent photocatalytic activity in both UV and infrared spectra, highlighted with the fact that (CaY)F2:Tm3+,Yb3+ nanocrystals can be excited to release UV light under near infrared light source, which can in consequence active TiO2. When the mass ratio of TiO2 to (CaY)F2:Tm3+,Yb3+ nanocrystals is 2:1, the best photocatalytic efficiency can be achieved with most of UV light released by (CaY)F2:Tm3+,Yb3+ absorbed by TiO2 to induce photo‐oxidation. The outstanding photocatalytic performance along with its biocompatibility, makes TiO2/(CaY)F2:Tm3+,Yb3+ a promising candidate in environmental and biomedical applications.