ZnO flowerlike microspheres loaded with upconversion nanoparticles for high-performance NIR-driven photocatalytic activity

Herein, we demonstrate a facile physical mixing method for synthesis of NaYF4:Yb,Tm,Nd@NaYF4:Yb,Nd upconversion nanoparticles (UCNPs)-loaded ZnO flowerlike microspheres with uniform size distribution. The designed structure of the composite materials exhibit high surface area and good stability, and favor the improvement of solar energy utilization and efficient energy transfer between UCNPs and ZnO semiconductors, benefitting from upconversion effect. To be more specific, lanthanide-doped UCNPs can convert long wavelength NIR light to short wavelength UV/visible emission which can be reabsorbed by ZnO and used for photocatalysis. The NIR light-responsive photocatalytic activity of the hybrid catalyst toward Rhodamine B (RhB) degradation was examined, and the significant enhancement was observed. Moreover, the antibacterial test against B. subtilis indicates that the hybrid catalyst has excellent antibacterial property under 808 nm NIR irradiation. (C) 2021 Elsevier B.V. All rights reserved.