Yazar "Manda, Abdullah A." seçeneğine göre listele

Listeleniyor 1 - 4 / 4
  • Küçük Resim
    Öğe
    Enhanced photocatalytic degradation of methylene blue by nanocomposites prepared by laser ablation of Bi on CNT-a-Fe2O3 nanoparticles
    (Elsevier Sci Ltd, 2022) Manda, Abdullah A.; Elsayed, Khaled; Gaya, Umar İbrahim; Haladu, Shamsuddeen A.; Ercan, İsmail; Ercan, Filiz; Alheshibri, Muidh
    The low conductivity and high combination rate of photogenerated electrons (e-) and photogenerated holes (h+) are the real challenges of photocatalysis. These problems could be mitigated by the synthesis of heterostructured nanocomposites (NCs). In this study, Bi@CNT-Fe2O3 nanocomposite was fabricated via pulsed laser ablation in liquid and characterized by UV-Vis spectroscopy, photoluminescence (PL), X-ray diffraction (PXRD) and field scanning electron microscopy (FESEM). These techniques revealed successfully the formation of CNT-alpha-Fe2O3 and Bi@CNT-alpha-Fe2O3 nanocomposites. The photocatalytic activities of the Fe2O3, CNT-alpha-Fe2O3, and Bi@CNT-Fe2O3 photocatalysts were evaluated by the degradation of methylene blue (MB) dye under ultraviolet (UV) light irradiation in the presence of a very low concentration of hydrogen peroxide (H2O2) as an oxidizing agent. The results show that the Bi@CNT-alpha-Fe2O3 NC has the highest photocatalytic degradation efficiency of MB which completes in 20 min of UV light irradiation. In addition, the obtained rate constants (min-1) of Bi@CNT-alpha-Fe2O3 NC were 1.3 and 3.4 times higher than those of CNT-alpha-Fe(2)O(3 )and alpha-Fe2O3. nanocatalysts, respectively.
  • Küçük Resim
    Öğe
    Fast one-pot laser-based fabrication of ZnO/TiO2-reduced graphene oxide nanocomposite for photocatalytic applications
    (Elsevier Ltd, 2023) Manda, Abdullah A.; Haladu, Shamsuddeen A.; Elsayed, Khaled; Gaya, Umar İbrahim; Alheshibri, M.; Al, Baroot, A.; Çevik, Emre
    Laser synthesis is rapidly emerging to be an efficient and unique method for the synthesis of a wide spectrum of nanomaterials owing to its ease of setup, simplicity, and generation of high-purity nanomaterials. This study explores a pulse laser ablation protocol in the synthesis of ZnO-TiO2 (ZT) and ZnO-TiO2-reduced graphene oxide (ZT-rGO) nanocomposites. The effect of rGO loading (5 %, 10 %, and 20 %) was investigated on the nature of the crystalline nanostructures formed, the increased thermal stability achieved, and the effective removal of methylene blue dye. Following fabrication, the nanocatalyst materials were characterized by TEM, PXRD, SEM/EDX, AFM, UV–Vis, TGA, and FTIR. Using UV illumination, the as-synthesized photocatalysts were evaluated in the photodegradation of methylene blue (MB) as a model dye pollutant. Among the nanocomposites, the ZT-rGO 5 % shows the best photocatalytic activity by having a preferential rate constant of 0.149 min?1. The nanocomposites were prepared in 30 min, providing 98.5 % MB removal within just 30 min, using 10 mg/L of MB and 20 mg/L of the catalyst. During the photodegradation process, the rGO component serves as an electron trap, thus enhancing the formation of holes which are the mainstay of any photocatalytic process. As demonstrated by the work reported, the laser ablation technique shows great promise in the fabrication of ZT-rGO nanocomposites and similar analogs relevant to the efficient decolorization of wastewater. © 2022 Elsevier Ltd
  • Küçük Resim Yok
    Öğe
    Pulsed laser ablation-mediated facile fabrication of MoO3/TiO2/rGO nanocomposite as a photocatalyst for dye degradation
    (Elsevier Sci Ltd, 2024) Al-Otaibi, Amal L.; Elsayed, Khaled A.; Manda, Abdullah A.; Haladu, Shamsuddeen A.; Gaya, Umar Ibrahim; Ercan, Filiz; Kayed, T. S.
    In this work, for the first time, the MoO3/TiO2/rGO nanocomposites with different weight ratios of rGO (0%, 5%, 10%, and 20%) were fabricated using pulsed laser ablation technique. The as-fabricated nanocomposites were employed for photodegradation of Methylene Blue (MB) under UV light irradiation. The morphological, struc-tural, and chemical properties of the fabricated photocatalysts were characterized using XRD, TEM, SEM, UV -DRS, XPS, FTIR, TGA, DSC, and PL. Comparative experimental studies displayed that MoO3/TiO2/rGO nano -composites fabricated with 5% rGO showed the highest photocatalytic degradation (95%) of MB under UV irradiation. This superior photocatalytic performance could be ascribed to the narrow bandgap of the fabricated nanocomposites as well as the synergistic effect of the three components.
  • Küçük Resim
    Öğe
    Structural, optical and photocatalytic properties of cerium doped Ba2TiMoO6 double perovskite
    (Elsevier B.V., 2023) Ghrib, Taher; Al-Otaibi, A.; Ercan, F.; Manda, Abdullah A.; Özçelik, Beraat; Ercan, İsmail
    Ce doped Ba2TiMoO6 nanomaterials with different Ce concentrations were synthesized by solid state technique. It was determined by the XRPD method that the atomic and molecular structures of Ba2Ti1-xCexMoO6 [x=(1,3,5,7)%] compound was in the tetragonal crystal system and crystallized in the P4mm space group. The purification parameters were found to be gof 1.2 and Rf 1.60. The Scanning Electron Microscopy, Transmission Electron Microscopy, and surface area analysis were used to examine the surface morphology. The UV–Vis diffuse reflectance and photoluminescence spectroscopies were used to investigate the optical properties. The study results showed the successful synthesis of pure and Ce doped Ba2TiMoO6 nanopowders, characterized by 8–20 nm grain size, 3.41–3.6 eV bandgap, and violet emission at 426.67 nm wavelength. The photocatalytic activities of the produced samples were tested against Methyl and it was observed that these activity values increased with the percentage of Ce doping. © 2022 Elsevier B.V.