Remarkably improvement in antibacterial activity by synergistic effect in n-Cu@T-ZnO nanocomposites

In view of its essential activity for antimicrobial, tetra-needle like ZnO (T-ZnO) were used as the carrier for in situ synthesizing well-dispersed nano-copper (n-Cu), to prepare a composite antibacterial agent for improving the activity and broadening the spectrum. The obtained hybridizing materials were characterized by electron microscopic observations, X-ray diffraction and X-ray photoelectron spectroscopic analyses, and the results showed that the n-Cu with an average size of 15 nm were uniformly loaded on surfaces of T-ZnO. The existence of special interactions between copper and T-ZnO was also approved. The as-prepared hybrids displayed much higher activity as compared to the pristine T-ZnO, the n-Cu alone, and even the identical copper amount of CuCl2 solution against Escherichia coli and Staphylococcus aureus. Based on systematically characterization and analyses, we attributed it to the synergistic effect resulted from the structural hybridization between the single-crystalline T-ZnO and n-Cu which lead to the increase of copper ions release and H2O2 generation. This discovery can be developed an effective approach towards a new kind of wide spectrum and high efficiency antibacterial materials. (C) 2016 Elsevier Ltd. All rights reserved.