Fabrication of Zinc Oxide Composite Microfibers for Near-Infrared-Light-Mediated Photocatalysis

Graphical ZnO way ! ZnO composite microfibers with different microstructures and embedded with a high population of upconversion nanoparticles are fabricated and show an excellent photocatalytic ability driven by near-infrared light. The fabrication of photocatalysts driven by near-infrared (NIR) light is of great scientific and technological interest to make use of solar energy. NaYF 4 codoped with Yb 3+ and Tm 3+ upconversion nanoparticles are important nanotransducers that transfer NIR photons to high-energy photons (UV/Vis). In this work, we demonstrated an electrospinning technique to synthesize ZnO and porous ZnO composite microfibers embedded with a large amount of NaYF 4 :Yb/Tm@NaYF 4 nanoparticles. The morphologies, chemical compositions, and phase of the as-prepared composites were investigated carefully by using field-emission scanning electron microscopy, TEM, X-ray photoelectron spectroscopy, fluorescence spectroscopy, and XRD. Steady-state and dynamic-state fluorescence spectra were used to demonstrate that the embedded NaYF 4 :Yb/Tm@NaYF 4 core–shell nanoparticles can activate the ZnO nanoparticles under IR irradiation. The ZnO composite microfibers can efficiently transfer the NIR photons to the excited state of ZnO and activate the semiconductor to produce reactive oxygen species to result in the degradation of rhodamine B dyes.