Effect of Ag/ZnO-Graphitic Carbon Nitride on Antimicrobial Activity under Visible Light

Abstract

Zinc oxide-graphitic carbon nitride (ZnO/g-C3N4) composites were synthesized by precipitation method in order to improve photocatalytic activity under visible light. To enhance antimicrobial activity, silver was added into zinc oxide-graphitic carbon nitride (Ag/ZnO/g-C3N4). Ultrastructures of the composite were analyzed by X-ray diffractometry (XRD) and transmission electron microscopy (TEM). Photocatalytic activity of the composites was carried out by degradation of methylene blue solution as a function of contact time. The results revealed that ZnO/g-C3N4 was capable of dye degradation at 96.65%. Addition of Ag into ZnO/g-C3N4 resulted in increase of dye reduction rate. For antibacterial test, Ag/ZnO/g-C3N4 exhibited bactericidal activity against Pseudomonas aeruginosa and Bacillus cereus. For antifungal test, Ag/ZnO/g-C3N4 showed resistance to Aspergillusniger for 7 days. Ag/ZnO-g-C3N4 composite exhibited better photocatalytic and antimicrobial activities compare to ZnO and g-C3N4. These results indicate that precipitation method is a cheap, rapid and efficient method that can be used to synthesize Ag/ZnO-g-C3N4 composites. For further studies, applications of this Ag/ZnO-g-C3N4 composites in microbiological and agricultural fields will be carried out.

Silver Nanoparticle-Embedded Carbon Nitride: Antifungal Activity on Candida albicans and Toxicity toward Animal Cells

“…In relation to Ag@g-CN, the previous study reported an antibacterial activity against both Gram-positive and Gram-negative bacteria, with a significant alteration in the bacterial growth within 60 min of exposure at 30 μg/mL concentration . However, this study failed to address the impact of intact g-C 3 N 4 on tested bacterial strains . In support to this argument, the melamine-mediated Ag/ZnO/g-C 3 N 4 composite produced significant antibacterial activity on E.…”

“…The g-CN nanosheet was inactive against both resistant and susceptible bacterial strains to antibiotics, but an antimicrobial activity was found when silver ions were added to g-CN. Furthermore, addition of 1 and 5% silver ions gradually improved the antibacterial activity with the MIC ranges of 125–250 and 31.2–62.5 μg/mL, respectively. , A similar observation was made by Rodmuang et al when 0.5 and 1% silver ions were added on the ZnO/g-C 3 N 4 composite …”