Advanced near-infrared-driven photocatalyst: Fabrication,characterization, and photocatalytic performance of β-NaYF4:Yb3+,Tm3+@TiO2core@shell microcrystals
The β-NaYF4:Yb3+,Tm3+@TiO2 core@shell photocatalyst has been successfully fabricated by a simply hydrothermal method followed by hydrolysis of titanium isopropoxide (TTIP) with polyvinylpyrrolidone K-30 (PVP) as the coupling agent. The advanced near-infrared-driven photocatalyst was characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, fluorescence spec-trometer and UV–vis–NIR diffuse reflectance spectroscopy. It is found that β-NaYF4:Yb3+,Tm3+@TiO2 core@shell photocatalyst consists of uniform hexagonal phase NaYF4 microcrystals rods and anatase TiO2 shells, and the β-NaYF4:Yb3+,Tm3+@TiO2 exhibits strong near-infrared light absorption and the energytransfers from β-NaYF4:Yb3+,Tm3+ to TiO2 is confirmed. The photocatalytic activities of the catalysts were evaluated by the discoloration of Methylene Blue, Methyl Orange and Rhodamine B under the irradiation of 980 nm laser. The results suggest that β-NaYF4:Yb3+,Tm3+@TiO2 core@shell composite is an advanced near-infrared-driven photocatalyst. Moreover the NIR-driven photocatalyst shows good stability for pho-tocatalytic decoloration of dye in the recycled tests. This study suggests a promising system to utilizethe NIR energy of sunlight for photochemical and photoelectrical applications based on TiO2, which willcontribute to the utilization of solar energy in the future.
