TEMPO-oxidized cellulose beads embedded with Au-doped TiO2 nanoparticles for photocatalytic degradation of Tylosin

Due to its hydrophilicity, the antibiotic tylosin (TYL) was challenging to remove entirely from water through traditional techniques. The design of an efficient photocatalyst for the degradation of TYL is a matter of great urgency. Herein, carboxylated cellulose beads embedded with Au-doped TiO2 nanoparticles (Au/TiO2-CCBs) were fabricated via interfacial solid-phase chemical modification with straightforward photo-deposition and TEMPO-mediated oxidation. Morphology, structure, and optical properties of Au/TiO2-CCBs have been investigated through scanning electron microscopy, energy dispersive spectrometer, Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, UV-vis Diffused reflectance spectra, and electron spin resonance (ESR). The fabricated Au/TiO2-CCBs exhibited superior photocatalytic performance, by demonstrating approx. 92% of TYL was decomposed in 180 min under visible light irradiation. However, the catalyst exhibited modest adsorption behavior. The enhanced photocatalytic activity for Au/TiO2-CCBs was attributed to the separation of photoinduced electron-hole pairs. The radical capture test and ESR experiment confirmed that center dot O-2(-), center dot OH, and h(+) radicals were formed during the TYL degradation process. In addition, the stability of the Au/TiO2-CCBs was demonstrated by a steady photocatalytic performance after five cycles during the application. Therefore, this work indicated that the Au/TiO2-CCBs catalyst had an excellent prospect for environmental remediation. [GRAPHICS] .