Green Synthesis of an Activated Carbon-Supported Ag and ZnO Nanocomposite for Photocatalytic Degradation and Its Antibacterial Activities

Abstract

In this study Ag nanoparticles (AgNPs), ZnO nanoparticles (ZnONPs), and Ag/ZnO nanocomposites were greenly synthesized and loaded on activated carbon via three different routes: simple impregnation, successive precipitation, and co-precipitation. Neem leaf extract was used as a reducing and stabilizing agent. The morphological and structural properties of the synthesized nanocomposites have been examined using different analytical techniques such as XRD, SEM, FTIR, and UV. The antibacterial and catalytic activity of the synthesized nanocomposites were examined and compared. The results showed that AgNPs loaded on activated carbon (Ag/AC) has the best catalytic activity compared to the other nanocomposites, which is attributed to the good dispersal of AgNPs on the surface of activated carbon. Furthermore, AgNPs showed the best antibacterial effect on eight out of 16 tested pathogens. Results also showed that the order of precipitation is an important factor, as both antibacterial activities and photodegradation activities were higher for ZnO/Ag/AC than Ag/ZnO/AC. Furthermore, the co-precipitation method was shown to be better than the successive precipitation method for 4-nitrophenol photodegradation and 14 out of the 16 antibacterial tests performed.

Biosynthesis of zinc oxide and silver/zinc oxide nanoparticles from Urginea epigea for antibacterial and antioxidant applications

“…Tables 2 and 3 present some selected results of the antibacterial and antioxidant activities of ZnO and Ag/ZnO NPs respectively from different plant extracts reported in the literature. The biosynthesized nanoparticles using different parts of plants display varying degrees of potency against the different pathogenic bacteria including Escherichia coli , Pseudomonas aeruginosa, Streptococcus pneumoniae Bacillus subtilis, Klebsiella pneumonia, Enterococcus faecalis, Staphylococcus aureus, Proteus mirabilis, pyogenes, Proteus mirabilis, Salmonella typhi, etc (Ramesh, 2015; Happy et al., 2019 ; Noohpisheh et al., 2020 ; Taha et al., 2020 ). They also exhibited moderate to high antioxidant activities.…”

Biodegradable Alginate Films with ZnO Nanoparticles and Citronella Essential Oil—A Novel Antimicrobial Structure

“…The ROS are responsible for the antibacterial activity, as they will damage the bacterial membrane by oxidative stress. In the absence of light the antibacterial activity is smaller, but still noticeable, the most probable mechanisms involving nanoparticle internalization and some mechanical damage, like puncture or rupture of the bacterial cellular wall [ 27 , 28 , 29 , 30 ]. Very important, US-FDA consider ZnO as GRAS and acceptable as an active component in food packaging due to its good antimicrobial properties [ 31 , 32 , 33 ].…”

Comparison of cytotoxicity of Ag/ZnO and Ag@ZnO nanocomplexes to human umbilical vein endothelial cells in vitro

“…In this study, we found that Ag/ZnO and Ag@ZnO NPs induced cytotoxicity to similar levels (Figure 3A). Recently, biocompatible Ag–ZnO nanocomplexes were synthesized for various biomedical applications (Ghaemi et al, 2018; Noohpisheh, Amiri, Farhadi, & Mohammadi‐Gholami, 2020; Taha, Ben Aissa, & Da'na, 2020). Hereby, our results suggested that the positions of Ag were not important to influence the biocompatibility of ZnO nanocomplexes.…”