Abstract
In this article we report the production of metal oxide (TiFe2O4, ZnFe2O4) nanoparticles by pulsed laser ablation technique in a liquid environment. We used nanosecond Nd: YAG laser systems working at 532 nm and 1064 nm of wavelength and the energy of the laser beam was kept constant at 80 mJ. Absorbance spectra, surface plasmon resonance, optical band-gap, and nanoparticle morphology were investigated using ultraviolet-visible (UV-Vis) spectroscopy, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Changing the wavelength of the laser for growth, nanoparticles showed shift between the absorbance and surface plasmon resonance peaks in their UV-Vis spectra, which implies that the optical properties of the colloid nanoparticles depend on laser parameters. This was confirmed with the variation of the band gap energy. Furthermore, redshift for the absorbance peak was observed for samples as-grown at 532 nm around 150 nm as a function of time preparation. Conversely, for the samples as-grown at 1064 nm there was no shift in the absorbance spectra, which could be due to agglomeration and formation of larger particles. The characterization results showed appropriate plasmonic photo-catalysts properties of the particles, hence the photoactivation of the nanoparticles was examined on antibacterial effect using colonies of Staphylococcus aureus and Escherichia coli.
Highlights
In recent years with the increasing applications of nanotechnology, nanomaterials like iron oxide (Fe3O4), titanium oxide (TiO2), and zinc oxide (ZnO) have been observed to show great properties for applications in heavy metals removal from polluted water, industrial wastewater treatment, biomedicine and photocatalysts [1,2,3,4,5,6,7]. This feature is due to properties of nanoparticles as nano-adsorbents removing heavy ions and because of their size having the ability to interact with light, yielding the confinement of light inside the nanoparticles (NPs) which generates new non-linear phenomena such as the collective oscillations of conduction band electrons in spherical metal nanoparticles excited by external electromagnetic field, so-called localized surface plasmon resonance (LSPR)
Because the ideal plasmonic photocatalysts should simultaneously act as an absorber to capture light as well as a catalytic surface to interact properly with surface intermediates, metal nanoparticles with strong light absorption capability have been demonstrated as a new family of plasmonic photocatalysts that offer distinctly different benefits compared to conventional semiconductor photocatalysts
As an example of this, Jianlong Wang et al 2010 have demonstrated that Fe3O4 magnetic nanoparticle can greatly enhance the localized surface plasmon resonance of metal nanoparticles in biological systems, and Nayareth Soltani et al 2012 have reported the degradation of methylene blue by visible light induced in the presence of photocatalytic ZnS and CdS nanoparticles [10,11,12,13,14]
Summary
In recent years with the increasing applications of nanotechnology, nanomaterials like iron oxide (Fe3O4), titanium oxide (TiO2), and zinc oxide (ZnO) have been observed to show great properties for applications in heavy metals removal from polluted water, industrial wastewater treatment, biomedicine and photocatalysts [1,2,3,4,5,6,7] This feature is due to properties of nanoparticles as nano-adsorbents removing heavy ions and because of their size having the ability to interact with light, yielding the confinement of light inside the nanoparticles (NPs) which generates new non-linear phenomena such as the collective oscillations of conduction band electrons in spherical metal nanoparticles excited by external electromagnetic field, so-called localized surface plasmon resonance (LSPR). Their antibacterial effect on colonies of Staphylococcus aureus and Escherichia coli was studied
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
