Yazar "Akkaya, Abdullah" seçeneğine göre listele

Listeleniyor 1 - 2 / 2
  • Küçük Resim
    Öğe
    A green approach for the preparation of nanostructured zinc oxide: Characterization and promising antibacterial behaviour
    (Elsevier, Ceramics International, 2021) Taşdemir, Abdülkadir; Aydın, Raşit; Akkaya, Abdullah; Akman, Nazife; Altınay, Yasemin; Çetin, Hidayet; Şahin, Bünyamin; Uzun, Aydın; Ayyıldız, Enise
    In the present study, nanostructured zinc oxide (ZnO) films have been successfully synthesized using fruit extract of Viburnum opulus L. (VO) on glass slides by successive ionic layer adsorption and reaction (SILAR) procedure. The impact of VO concentrations on the structural, morphological, optical, electrical, and antibacterial attributes of ZnO films has been investigated in detail. The samples' XRD patterns present a hexagonal crystal structure with a preferential orientation along the (002) plane. The crystallite size values of ZnO samples were found to be in the ranges from 14.88 to 9.23 nm. The supplementation of VO to the synthesis solution remarkably affected the surface morphological features of the ZnO films. The optical results demonstrated that band gap energy values of the ZnO films at room temperature were decreased from 3.20 to 3.07 eV as a function of VO content in the bath solution. The films' electrical properties were determined by impedance analysis in the frequency range of 20 Hz ?1 MHz. Impedance-frequency measurements showed VO insertion to ZnO thin films cause an increase in impedance value at the low frequencies. Cole-Cole plots with a single semi-circle confirmed the contribution of grain and grain boundary for the electrical conduction process. The agar disk diffusion method was used to test the antibacterial properties of ZnO/VO inserted ZnO and inhibition zones were measured. VO inserted ZnO showed a stronger inhibitory effect on gram-positive bacteria Staphylococcus aureus (ATCC 25923) and gram-negative bacteria Escherichia coli (ATCC 35218) than ampicillin antibiotic used as a control group. In line with the promising bactericidal results of a new generation, VO inserted ZnO, the nanostructured product with this study, it can also be applied in multidrug-resistant clinical isolates obtained from patients.
  • Küçük Resim
    Öğe
    Green and cost-effective synthesis of zinc oxide thin films by L-ascorbic acid (AA) and their potential for electronics and antibacterial applications
    (elsevier, 2021) Taşdemir, Abdulkadir; Akman, Nazife; Akkaya, Abdullah; Aydın, Raşit; Sahin, Bünyamin
    The evolution of eco-friendly, green route and cheap technology for synthesizing nanostructured zinc oxide (ZnO) thin films using plant extracts is a promising choice because such materials present a widespread potential for numerous technological applications. This study proposes the green and cost-effective technique to synthesize stable ZnO thin films using a good reducing agent and facilitating many natural L-ascorbic acids (AA) metabolic reactions capacity. The influence of AA concentrations in the starting bath solution on ZnO samples' structural, morphological, electrical and antibacterial performances has been reported in detail. The main physical characteristics of the ZnO materials were improved by supplementing of reducing and capping agents AA. Average particle size varies with the adding AA from 58.29 to 48.68 nm and also thickness of these films was decreased from 0.82 to 0.44 ?m. Also, it was seen that, the presence of AA in the bath solution significantly affected the absorption process and causes a morphological alteration due to the reaction between Zn2+ and AA during the deposition process. FTIR transmittance spectra of bare ZnO presented that a transmittance peak about 886 cm?1 and 748 cm?1 was created by the characteristic stretching vibration mode of the Zn–O. The resistivity of the produced films significantly changed with AA concentration in the bath solution. Antibacterial potentials of bare ZnO and ascorbic acid added ZnO films were examined against economically important Staphylococcus aureus (ATCC 25923) gram-positive bacteria and Escherichia coli (ATCC 35218) gram-negative bacterial disease agents via handling paper disc diffusion assay. The obtained diameter of the zones of inhibition was 20.1 mm for E. coli and 28.1 mm for S. aureus at the dose of ZnO+AA 8.0%. These inhibition diameters were larger than the diameter of ampicillin as our positive control alone. This proves that the newly synthesized compound is a powerful antibacterial agent.