Toward NIR driven photocatalyst: Fabrication, characterization, and photocatalytic activity of β-NaYF4:Yb3+,Tm3+/g-C3N4 nanocomposite

The β-NaYF4:Yb3+,Tm3+/g-C3N4 (NYT/C3N4) photocatalyst has been successfully fabricated by a stepwise method. Firstly, the advanced near-infrared (NIR) driven photocatalyst was characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and UV–Vis–NIR diffuse reflectance spectroscopy. It was found that NYT/C3N4 photocatalyst consisted of uniform hexagonal phase NaYF4 nanocrystals with about 20 nm diameter distributed on surface of g-C3N4 sheets, and the NYT/C3N4 composite exhibited strong near-infrared light absorption and the energy transfer from β-NaYF4:Yb3+,Tm3+ to g-C3N4 was confirmed. Secondly, the photocatalytic activities of the catalysts were evaluated by the degradation of methyl blue dye and colorless phenol under the irradiation of 980 nm laser. The results suggested that NYT/C3N4 nanocomposite is an advanced NIR-driven photocatalyst. Moreover the NYT/C3N4 photocatalyst showed good stability for photocatalytic decoloration of dye in the recycled tests. This study suggested a promising system to utilize the NIR energy of sunlight for photochemical and photoelectrical applications based on g-C3N4, which will contribute to the utilization of solar energy in the future.

Graphical abstractThe β-NaYF4:Yb3+,Tm3+/g-C3N4 (NYT/C3N4) photocatalyst, consisted of uniform hexagonal phase NaYF4 nanocrystals distributed on the surface of g-C3N4, has been successfully fabricated by a stepwise method and the composite exhibited excellent photocatalytic activity under the irradiation of 980 nm laser as evaluated by the degradation of Methyle Blue and phenon as pollutant models.Figure optionsDownload full-size imageDownload high-quality image (117 K)Download as PowerPoint slide