Incorporation of Fe and Cu for antibacterial performance enhancement of Fe-Cu-ZnO nanocomposites synthesized by a facile chemical precipitation

Abstract

Fe-Cu-ZnO nanocomposites were synthesized using simple chemical precipitation under a violent stirring condition, and characterized by dynamic light scattering, ultraviolet-visible spectroscopy, scanning electron microscopy, X-ray diffractometry, Raman spectroscopy, and vibrating sample magnetometer. The particle size distribution is observed not only a large size of 100 nm to 2 mm, but also a small size of 0.4-5.0 nm. The absorbance peaks of the nanocomposites exhibit a small blue shift in comparison with ZnO. Surface defects are explored in the nanocomposites including irregular shapes, rough surfaces, and aggregation. The nanocomposites and ZnO have similar hexagonal wurtzite structures. However, the nanocomposites have more crystal defects than ZnO due to ZnFe₂O₄ formation. Although the presence of zinc ferrite (ZnFe₂O₄) is also detected, magnetic hysteresis is disappeared because of poor ZnFe₂O₄ distribution and critical size effects. In antibacterial test, the nanocomposites were applied to inhibit the growth of Xanthomonas campestris, Pseudomonas aeruginosa, and Pseudomonas fluorescens. It is found that antibacterial performance is enhanced relating to surface and crystal defects. These defects are possible to increase interfacial contacts and accelerate antibacterial activities for the antibacterial enhancement. Therefore, the Fe-Cu-ZnO nanocomposites are alternative potential material appropriately for bacterial inhibition application.