Green synthesis of spongy Nano-ZnO productive of hydroxyl radicals for unconventional solar-driven photocatalytic remediation of antibiotic enriched wastewater

Amr A Essawy; Ibrahim Hotan Alsohaimi; Mosaed S Alhumaimess; Hassan M A Hassan; Mahmoud M Kamel

doi:10.1016/j.jenvman.2020.110961

Green synthesis of spongy Nano-ZnO productive of hydroxyl radicals for unconventional solar-driven photocatalytic remediation of antibiotic enriched wastewater

J Environ Manage. 2020 Oct 1:271:110961. doi: 10.1016/j.jenvman.2020.110961. Epub 2020 Jun 30.

Authors

Amr A Essawy¹, Ibrahim Hotan Alsohaimi², Mosaed S Alhumaimess³, Hassan M A Hassan⁴, Mahmoud M Kamel³

Affiliations

¹ Chemistry Department, College of Science, Jouf University, Sakaka, P.O. Box 2014, Saudi Arabia; Chemistry Department, Faculty of Science, Fayoum University, 63514, Fayoum, Egypt. Electronic address: aae01@fayoum.edu.eg.
² Chemistry Department, College of Science, Jouf University, Sakaka, P.O. Box 2014, Saudi Arabia. Electronic address: ehalshaimi@ju.edu.sa.
³ Chemistry Department, College of Science, Jouf University, Sakaka, P.O. Box 2014, Saudi Arabia.
⁴ Chemistry Department, College of Science, Jouf University, Sakaka, P.O. Box 2014, Saudi Arabia; Department of Chemistry, Faculty of Science, Suez University, Suez, Egypt.

PMID: 32778271
DOI: 10.1016/j.jenvman.2020.110961

Abstract

Herein, novel green/facile approach to synthesize spongy defective zinc oxide nanoparticles (ZnONPs) is presented using for the first time pomegranate seeds molasses as a green capping fuel/reducing mediator during an aqueous solution combustion process. The developed ZnONPs is characterized by UV-Vis. Spectrophotometry and fluorimetry, XRD, Raman spectroscopy, SEM, TEM and BET. Interestingly, pomegranate seeds molasses within a viable content of bio-capping molecules reveal a defective nanoporous ZnO NPs of smaller particle size, greater pore size/volume, and higher surface area compared to the bulky non-biogenic ZnONPs. Moreover, the biosynthesized defective ZnONPs showed narrowed band gap and higher absorption of visible photons that breed higher density of hydroxyl radicals (^•OH) under Solar-illumination. Even further, the bulk ZnO and the biosynthesized ZnO photocatalysts were examined in photodegrading flumequine (FL) antibiotic. The bulk ZnO gives 41.46% photodegradation efficiency compared to 97.6% for the biosynthesized ZnO. In highly acidic or highly alkaline media, FL photodegradability is greatly retarded. Scavenging experiment infers considerable contribution of holes over electrons in photodegradation reaction. The biosynthesized ZnO shows high durability in FL photodegradation after four reusing cycles. These promising findings highlight new insights for biogenic synthesis of tuned size/controlled morphology semiconductor NPs relevant to environmental remediation applications.

Keywords: Antibiotic wastewater remediation; Flumequine photocatalytic degradation; Green synthesis; Hydroxyl radicals; Solar-illumination; ZnO defective Nanoparticles.

MeSH terms

Anti-Bacterial Agents
Hydroxyl Radical
Plant Extracts
Wastewater
Zinc Oxide*

Substances

Anti-Bacterial Agents
Plant Extracts
Waste Water
Hydroxyl Radical
Zinc Oxide