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Subject: Titanium dioxide

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Now showing 1 - 5 of 5
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    Conference Object
    Citation - WoS: 1
    PRODUCTION OF SILVER LOADED PHOTOCATALYTIC TIO2 POWDERS BY BALL MILLING
    (Tanger Ltd, 2011) Aysin, Basak; Park, Jongee; Ozturk, Abdullah
    The present study was undertaken to improve photocatalytic efficiency of TiO2 powder by silver doping and/or particle size reduction through mechanical ball milling. A planetary ball mill was employed to reduce the particle size of TiO2 powders to nanoscale and silver loading to TiO2 powders. Silver nitrate was used as silver source to obtain about 1% Ag load. Slurry taken from ball mill was separated by centrifugal separator into nano and micro sols. Separated nanosol was taken into the furnace to be dried at 103 degrees C and calcined at 400 degrees C for 1 hour to assist silver loading. X-Ray powder diffraction (XRD) was employed to identify the crystalline phases present in the powders produced. XRD results revealed that doped TiO2 powders were consisted of only anatase phase of TiO2. Changes in lattice parameters of TiO2 structure after doping were determined also by XRD. Scanning Electron Microscope (SEM) and particle size analyzer were used for examining the size reduction effect of ball milling process. Photocatalytic performance of the powders was evaluated by Methylene Orange (MO) test under UV light illumination using UV-Spectrophotometer.
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    Article
    Citation - WoS: 146
    Citation - Scopus: 163
    Polybenzimidazole Based Nanocomposite Membranes With Enhanced Proton Conductivity for High Temperature Pem Fuel Cells
    (Pergamon-elsevier Science Ltd, 2017) Ozdemir, Yagmur; Uregen, Nurhan; Devrim, Yilser
    In this study, phosphoric acid doped PBI nanocomposite membranes were prepared by dispersion of various amounts of inorganic nanoparticles in PBI polymer followed by phosphoric acid (H3PO4) doping for high temperature proton exchange membrane fuel cells (HT-PEMFC). All of the PBI composite membranes were cast from the same FBI polymer with the same molecular weight. Titanium dioxide (TiO2), silicon dioxide (SiO2) and inorganic proton conductor zirconium phosphate (ZrP) were used as inorganic fillers. The PBI based composite membranes were characterized in terms of their acid uptake and acid leaching properties, mechanical properties, chemical stabilities in N-N Dimethylacetamide (DMAc) and impedance analyses. Thermal gravimetric analysis confirmed the improved thermal stability of the PBI composite membranes. The existence of inorganic fillers was improved the acid retention capability. Electrochemical Impedance Spectroscopy (EIS) showed that the introduction of 5 wt. % SiO2 or 5 wt. % ZrP helps to increase proton conductivity. The composite membrane with TiO2 retained low conductivity values than pristine PBI and this is a result of its non-uniform membrane structure. The highest proton conductivity of 0.200 S/cm was obtained for PBI/ZrP composite membrane with the highest value of H3PO4 doping level. Nyquist plots are drawn for all the membranes at different temperatures and the plots showed good fit with Randel's circuit. As a result the experimental results suggested that the PBI based composite membranes may be a promising electrolyte used in HT-PEMFC. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
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    Master Thesis
    Titanyum Dioksit Nanopartikülleri Eklenmiş Polianilin Hazırlanması ve Antibakteriyel Yanıt Analizi
    (2022) Altmarı, Maha; İşgör, Sultan Belgin; Kaya, Murat
    Because of an increase the bacterial attack in different sectors of our life, it become necessary to search about a new antibacterial material.The aim of this research is to produce an anti-bacterial and environmentally friendly material used as a surface coating to reduce diseases caused by bacterial infection. In this work, we prepared polyaniline (PANI) by using the chemical polymerization of aniline with ammonium persulfate (APS), after that we used commercially available titanium dioxide nanopowder for preparation (PANI-TiO2) nanocomposite material by chemical polymerization.The morphologies, structures, and elemental composition of the nanocomposite material are characterized by using TEM, SEM and EDX. After that,study the antibacterial activity of TiO2, PANI and(PANI-TiO2) nanocomposite was investigated by using E. coli and S. aureus.The results of this study show that no antibacterial effect of TiO2 and PANI NPs for each type of bacteria, but the antibacterial effect for (PANI- TiO2) was very weak on S. aureus and very strong on E. coli.
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    Master Thesis
    Titanyum Dioksit ve Manyetik Nanoparçacık İçeren Yüksek Kükürt İçerikli Polimerik Kompozitlerin Sentezi ve Fotokatalitik Uygulamaları
    (2022) Topcuoğlu, Mert; Kaya, Murat; Cihaner, Atilla
    Doğada en çok bulunan elementlerden birisi olan kükürt zehirli olmayıp açık havada depolanmasına rağmen yanıcı bir katıdır. Her yıl petrol rafinerilerinden yan ürün olarak yaklaşık 70 milyon ton kükürt elde edilmesine rağmen bu devasa miktardaki kükürtün kullanım alanı çok sınırlıdır. Bu nedenle elementel kükürtün katma değeri yüksek ürünlere (polimerler gibi) dönüştürülmesi ve endüstride büyük miktarlarda kullanım bulmasını sağlamak önemlidir. Bu projede bitkisel yağ asitleri kullanarak yeni yüksek kükürt içerikli polimerik malzemelerin sentezi ve metilen mavisi gideriminde kullanılacak fotokatalizör için destek malzemesi olarak kulanımı hedeflenmiştir. Bu amaçla ters vulkanizasyon yöntemi ile elemental kükürt ve yağ asiti, linolenik asit (LnA), kopolimerizasyonu gerçekleştirilmiştir. Elde edilen polikükürt kopolimerin fotokatalitik etkinliği solar simulator altında metilen mavisinin bozunmasında denenmiştir. Daha sonra polikükürt kopolimere manyetik nanoparçacık ve titanyum dioksit nanoparçacık eklenerek tekrar hazırlanmış ve kompozit malzeme, poly(S-r-FA)-TiO2-MNP, elde edilerek fotokatalitik etkinliği incelenmiştir. Daha sonra kompozit malzeme ile kararlılık çalışması yapılmıştır. Hazırlanan mazlemelerin karakterizasyonları SEM, TEM, EDX, FTIR ve NMR kullanılarak gerçekleştirilmiştir. Boya derişimindeki azalma UV-Vis spektrometresi ile takip edilmiştir.
  • Thumbnail Image
    Conference Object
    Citation - Scopus: 3
    Production of Silver Loaded Photocatalytic Tio2 Powders by Ball Milling
    (TANGER Ltd., 2011) Aysin,B.; Park,J.; Ozturk,A.
    The present study was undertaken to improve photocatalytic efficiency of TiO2 powder by silver doping and/or particle size reduction through mechanical ball milling. A planetary ball mill was employed to reduce the particle size of TiO2 powders to nanoscale and silver loading to TiO2 powders. Silver nitrate was used as silver source to obtain about 1% Ag load. Slurry taken from ball mill was separated by centrifugal separator into nano and micro sols. Separated nanosol was taken into the furnace to be dried at 103 °C and calcined at 400° C for 1 hour to assist silver loading. X-Ray powder diffraction (XRD) was employed to identify the crystalline phases present in the powders produced. XRD results revealed that doped TiO2 powders were consisted of only anatase phase of TiO2. Changes in lattice parameters of TiO2 structure after doping were determined also by XRD. Scanning Electron Microscope (SEM) and particle size analyzer were used for examining the size reduction effect of ball milling process. Photocatalytic performance of the powders was evaluated by Methylene Orange (MO) test under UV light illumination using UV-Spectrophotometer. © 2011 TANGER Ltd., Ostrava.