@article{e3127932bf17433faf4f9008a474e769,
title = "Silver nanoparticles modified ZnO nanocatalysts for effective degradation of ceftiofur sodium under UV–vis light illumination",
abstract = "Light-induced photocatalytic degradation of ceftiofur sodium (CFS) has been assessed in the presence of plasmonic zinc oxide nanostructures (ZnONSTs), like, ZnO nanoparticles, ZnO nanorods (ZnONRs) and ZnO nanoflowers (ZnONFs). Silver nanoparticles (Ag NPs) loaded ZnO nanostructures (Ag-ZnONSTs) are obtained through seed-assisted chemical reaction followed by chemical reduction of silver. The surface modification of ZnO nanostructures by Ag NPs effectually altered their optical properties. Further, the surface plasmonic effect of Ag NPs facilitates visible light absorption by ZnONSTs and improved the photogenerated electron and hole separation, which makes the ZnONSTs a more active photocatalyst than TiO2 (P25) nanoparticles. Especially, Ag-ZnONRs showed higher CFS oxidation rate constant (k' = 4.6 × 10−4 s−1) when compared to Ag-ZnONFs (k' = 2.8 × 10−4 s−1) and Ag-ZnONPs (k' = 2.5 × 10−4 s−1), owing to their high aspect ratio (60:1). The unidirectional transport of photogenerated charge carriers on the Ag-ZnONRs may be accountable for the observed high photocatalytic oxidation of CFS. The photocatalytic oxidation of CFS mainly proceeds through •OH radicals generated on the Ag-ZnONRs surface under light illumination. In addition, heterogeneous activation of peroxymonosulfate by Ag-ZnONRs accelerates the rate of photocatalytic mineralization of CFS. The quantification of oxidative radicals supports the proposed CFS oxidation mechanism. Stability studies of plasmonic Ag-ZnONSTs strongly suggests that it could be useful to clean large volume of pharmaceutical wastewater under direct solar light irradiation.",
keywords = "1D ZnO nanorods, Antibiotics contamination, Ceftiofur sodium, Photocatalytic oxidation, Plasmonic Ag–ZnO nanostructures",
author = "N. Pugazhenthiran and P. Sathishkumar and Omeer Albormani and S. Murugesan and M. Kandasamy and M. Selvaraj and S. Suresh and Kumar, {S. Karthick} and D. Contreras and H. V{\'a}ldes and Mangalaraja, {R. V.}",
note = "Funding Information: Light-induced photocatalytic degradation of ceftiofur sodium (CFS) has been assessed in the presence of plasmonic zinc oxide nanostructures (ZnONSTs), like, ZnO nanoparticles, ZnO nanorods (ZnONRs) and ZnO nanoflowers (ZnONFs). Silver nanoparticles (Ag NPs) loaded ZnO nanostructures (Ag-ZnONSTs) are obtained through seed-assisted chemical reaction followed by chemical reduction of silver. The surface modification of ZnO nanostructures by Ag NPs effectually altered their optical properties. Further, the surface plasmonic effect of Ag NPs facilitates visible light absorption by ZnONSTs and improved the photogenerated electron and hole separation, which makes the ZnONSTs a more active photocatalyst than TiO2 (P25) nanoparticles. Especially, Ag-ZnONRs showed higher CFS oxidation rate constant (k' = 4.6 × 10−4 s−1) when compared to Ag-ZnONFs (k' = 2.8 × 10−4 s−1) and Ag-ZnONPs (k' = 2.5 × 10−4 s−1), owing to their high aspect ratio (60:1). The unidirectional transport of photogenerated charge carriers on the Ag-ZnONRs may be accountable for the observed high photocatalytic oxidation of CFS. The photocatalytic oxidation of CFS mainly proceeds through •OH radicals generated on the Ag-ZnONRs surface under light illumination. In addition, heterogeneous activation of peroxymonosulfate by Ag-ZnONRs accelerates the rate of photocatalytic mineralization of CFS. The quantification of oxidative radicals supports the proposed CFS oxidation mechanism. Stability studies of plasmonic Ag-ZnONSTs strongly suggests that it could be useful to clean large volume of pharmaceutical wastewater under direct solar light irradiation.In view of the above facts, for first time, in the present paper, the photocatalytic efficiency of one-dimensional Ag-ZnONRs has been evaluated by following the kinetics of degradation of ceftiofur sodium (CFS). In addition, comparative photocatalytic degradation performance was studied for different Ag–ZnO nanostructures, such as Ag–ZnO nanoflowers (Ag-ZnONFs) and Ag–ZnO nanoparticles (Ag-ZnONPs). The surface modification, crystal phases, extended optical absorbance and charge recombination properties of the new synthesized Ag–ZnO nanostructures were comprehensively determined using different physio-chemical characterization techniques, such as high-resolution transmission electron microscopy (HR-TEM), X-ray diffraction (XRD), diffuse reflectance spectroscopy (DRS) and photoluminescence (PL) spectroscopy. The heterogeneous activation of peroxymonosulfate using plasmonic Ag-ZnONRs and their charge transfer and acceleration of photocatalytic activity were studied. The quantification of oxidative radicals during the CFS oxidation was used as an evidence to support the proposed reaction mechanism. Additionally, total organic carbon analysis allows identifying the degree of mineralization of CFS. Furthermore, stability and reusability of plasmonic Ag-ZnONSTs were also investigated.The author N. Pugazhenthiran gratefully acknowledges ANID/FONDECYT, Santiago, Chile for Initiation grant No. 11190600 for financial support. O. Albormani and M. Selvaraj extend their appreciation to the deanship of scientific research at King Khalid University, Saudi Arabia for the support through the Large Research Group Project under grant number R.G. P: 2/97/1443. The author P. Sathishkumar thank VIT, India for providing 'VIT SEED GRANT' File No.: SG20210261 for carryingout this research work. Funding Information: The author N. Pugazhenthiran gratefully acknowledges ANID/ FONDECYT, Santiago, Chile for Initiation grant No. 11190600 for financial support. O. Albormani and M. Selvaraj extend their appreciation to the deanship of scientific research at King Khalid University, Saudi Arabia for the support through the Large Research Group Project under grant number R.G. P: 2/97/1443 . The author P. Sathishkumar thank VIT, India for providing 'VIT SEED GRANT' File No.: SG20210261 for carryingout this research work. Publisher Copyright: {\textcopyright} 2022 Elsevier Ltd",
year = "2023",
month = feb,
doi = "10.1016/j.chemosphere.2022.137515",
language = "English",
volume = "313",
journal = "Chemosphere",
issn = "0045-6535",
publisher = "Elsevier Ltd.",
}