Synthesis of novel antibacterial nanocomposite CuO/Ag-modified zeolite for removal of MB dye.

Novel CuO/Ag nanocomposites added zeolite (CAZ) were successfully fabricated, and their effectiveness as an antibacterial on S. aureus and MB removal was evaluated. EDX, XRD, and FTIR confirm the presence of the elemental compositions of CAZ. Friable CuO nanorods (10-70 nm in diameter) existed on the surface of the zeolite. Pure zeolite had a higher band gap (5.433 eV) and lower MB removal efficiency than CAZ. The adsorption method by CAZ was more effective at removing MB than photodegradation. 0.10 CAZ had the highest removal effectiveness (~ 99%) and adsorption capacity (~ 70.4 mg g-1) of MB. The inhibitory zone diameter for 0.005 CAZ against S. aureus was 20 mm, while 0.01 CAZ had a diameter of 17 mm. Azithromycin, ceftriaxone, and erythromycin antibiotics demonstrated lower or no efficacy against S. aureus than CAZ. Significant antibacterial activities and wastewater treatment were achieved by CAZ. The combination of photodegradation and adsorption enhanced pollutant removal. It will be interesting to study further the optimal molar ratio for MB removal (0.10 CAZ) in future investigations.

Synthesis and comparative study on the structural and optical properties of ZnO doped with Ni and Ag nanopowders fabricated by sol gel technique.

In this work we have tried to prepare Ni and Ag doped ZnO nanopowders using the sol gel technique. The influence of Ni and Ag (1, 3 and 5 mol.%) on the crystalline structure and optical properties of ZnO was investigated. The samples were characterized by XRD, FTIR and UV-visible spectrophotometer. XRD patterns confirmed the wurtzite formation of doped and undoped ZnO nanopowders. The average crystallite sizes of the prepared samples found from XRD were 19 nm for undoped ZnO, from 17 to 22 nm for Ni-ZnO and from 19 to 26 nm for Ag-ZnO. The average crystallite size of Ag-ZnO increased with increasing Ag contents. Different optical properties of Ni-ZnO and Ag-ZnO nanopowders were observed for different Ni and Ag content. The band gaps of Ni-ZnO and Ag-ZnO nanopowders were lower than that of the undoped ZnO (3.1 eV). The band gaps of Ag-ZnO were lower than that of Ni-ZnO. The optical properties of ZnO were enhanced by Ni (mol.%) in the UV region and by Ag (3 and 5 mol.%) in the visible region.