Browsing by Author "Ekanayake, U.G.M."

Now showing 1 - 2 of 2
  • No Thumbnail Available
    Item
    Fabrication of Smart Umbrella Canopy with Super Hydrophobic Property
    (Uva Wellassa University of Sri Lanka, 2018) Ekanayake, U.G.M.; Rathuwadu, N.; Manthilaka, M.M.M.G.P.G.
    Super hydrophobic textiles are very popular in recent years due to their selfcleaning ability and non-wettability. However this useful property has limitedly been introduced to umbrella canopies. In this study, super hydrophobic umbrella canopy has been produced by a convenient method. Herein, existing umbrella canopy comprised of polyurethane (PU) and polyacrylic (PA) coated polyester was used to produce super hydrophobic umbrella which was provided by Rainco (Pvt) Ltd, a leading umbrella manufacturer in Sri Lanka. Zinc oxide (ZnO) nanostructures were grown on the fabric by dipping the fabric in a mixture of hexamethylenetetramine and zinc nitrate followed by heating the mixture at 100 °C for 2 h. The modified fabric was dried well and dipped in a solution of stearic acid for 15 h in order to self-assemble stearic acid on ZnO nanostructures. The final product was air-dried to obtain super hydrophobic umbrella canopy. PA and PU coated fabric has water contact angle of 1050. Scanning electron microscopic (SEM) images showed ZnO nanostructures with size range of 100 to 500 nm with spherical shape and rod shape on the surface of the fabric to make the surface rough. The resulted fabric showed super hydrophobicity with water contact angle of 155 °C and the sliding angle of 3 °C. The sample was further characterized using X-ray florescence (XRF), Thermo gravimetric analysis (TGA), Energy dispersive X-ray analysis (EDX), UV-Vis spectroscopy and Fourier transform infrared (FTIR) spectroscopy. The develop method is useful to fabricate super hydrophobic umbrella canopies.
  • Thumbnail Image
    Item
    In-situ Synthesis of Zinc Oxide Seeds on Thin Film of Mica as the Highly Reactive Photocatalyst Under UV-Light Irradiation
    (Uva Wellassa University of Sri Lanka, 2019) Senthilnathan, A.; Ekanayake, U.G.M.; Mantilaka, M.M.G.P.G.
    Structurally layered mica has attracted much attention of the mineralogists due to its unique structural properties. This study mainly concerns in developing the nano-seeds of Zinc oxide on thin film of mica (ZnO-mica) and the potential study of the photo-catalytic property under UV-light irradiation. The ZnO-mica was prepared by the In-situ growth of nanoparticles. 5 g of (0.5 cm × 0.5 cm) cut thin films of mica was added to the mixture of 600 µL, 50 mL of Cetyltrimethylammonium chloride (CTAC) and 2 mol dm-3, 50 mL of zinc nitrate hexahydrate. Then, Zn(OH)2 seeds were grown on the thin sheets of mica by adding 4 mol dm-3, 50 mL of NaOH solution with stirring for 24 hrs. The obtained product was then calcined at about 600 ℃. Finally, photo-catalytic property study was carried out in beakers containing 50 mL of Methylene Blue (MB) with various dose of (1.0, 3.0, 4.0 and 10.0 g) ZnO-mica. UV-Vis spectroscopy analysis was implemented with 30 min of time interval under the UV-light irradiation with initializing under dark condition for 30 min to 3.5 hrs. The synthesized final product was characterized by using the characterizing techniques such as X-ray powder diffraction and scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), Fourier transform infrared spectroscopy and thermo gravimetric analysis. The analytical data from the SEM reveal that the synthesized product with flower-like morphology having average particle length and width are 800 nm and 50 nm respectively. The crystallinity and the chemical analysis using XRD and FT-IR confirm the presence of ZnO on mica. The plot of percentage dye degradation versus time with increasing dosage under UV light indicates the rapid photo-catalytic dye degradation with increasing dosage of the photo-catalyst. The simple, flexible and novel method has been devised to develop the photo-catalyst under the UV-light irradiation.