Bu kaydın yasal hükümlere uygun olmadığını düşünüyorsanız lütfen sayfa sonundaki Hata Bildir bağlantısını takip ederek bildirimde bulununuz. Kayıtlar ilgili üniversite yöneticileri tarafından eklenmektedir. Nadiren de olsa kayıtlarla ilgili hatalar oluşabilmektedir. MİTOS internet üzerindeki herhangi bir ödev sitesi değildir!

Preparation Of Silver Nanoparticles Loaded Polyanilinetitanium Dioxide Nanocomposite Material And Usage In Environmental Remediation

Diğer Başlık: Gümüş Nanoparçacıkların Yüklendiği Polianilintitanyum Dioksit Nanokompozit Malzemenin Hazırlanması Ve Çevre Islahında Kullanımı

Oluşturulma Tarihi: 03-11-2020

Niteleme Bilgileri

Tür: Tez

Alt Tür: Doktora

Yayınlanma Durumu: Yayınlanmamış

Dosya Biçimi: PDF

Dil: İngilizce

Konu(lar): Kimya mühendisliği,

Yazar(lar): Elbuzedi, Mohamed Tuhami A. (Yazar),

Emeği Geçen(ler): Kaya, Murat (Tez Danışmanı), Tirkeş, Seha (Tez Danışmanı),


Yayın Tarihi: 05-02-2020


Dosya:
file show file
Görüntüle
download file
Kaydet

Anahtar Kelimeler

Photocatalysts, nanocomposites, environmental remediation, polyaniline, silver nanoparticles, TiO2 nanoparticles


Özet

In recent decades, environmental pollution due to toxic and carcinogenic organic dyes in the wastewater of many textile industries is a serious problem for human health. Therefore, the removal of these dyes in wastes is the way of resolving this environmental issue. The possible methods to achieve degradation of these toxic molecules into non-toxic components are adsorption, reverse osmosis, precipitation, and coagulation-flocculation. However, these techniques need further treatments and are not cost-effective. Among the several methods to solve this problem, Advanced Oxidation Processes (AOPs), which include extremely reactive anions (O2 − ) and radicals (•OH), have attracted great attention because of their potential utilization for wastewater treatment. These reactive oxygen species are released by the semiconductor photocatalysts after exposure by the UV or visible light. Numerous semiconducting catalysts such as ZnO, Fe2O3, SnO2, CdS, TiO2, etc. were used to remove organic dyes from the wastewater because of their unique properties in photocatalysis

The solar light-based photocatalytic activity has a prominent capability for the usage in environmental remediation. However, the insufficient activity of the semiconductor photocatalysts due to their large band gaps under visible irradiation is still preventing their applications. Many researchers have tackled to reduce band gaps of semiconductor photocatalysts to obtain maximum efficiency from the visible part of the solar spectrum by doping or co-doping with metal and nonmetal ions.

Besides the metal oxide semiconductors, conjugated polymer-based photocatalysts are emerging candidates, which use visible light for photocatalysis. In addition to its low toxicity, better stability, and low cost, polyaniline (PANI) has a high absorption coefficient in the visible range of light and high mobility of charge carriers. Moreover, under photo illumination, PANI is both a strong electron donor and a superb hole acceptor material. In order to increase the photocatalytic activity, noble metal modification, like gold, and silver, can be applied. The noble metal modification causes the formation of surface plasmon resonance effect on the surface of the polymer. The electronic field, which is generated on the photocatalytic material surface, can enhance the efficiency of charge (electron-hole) separation which is known as the key factor of the increase in photocatalytic efficiency. When the metal nanoparticles like Ag, Au, and Pt added to photocatalytic materials, the lifetime of e- -h + pairs increase due to their surface plasmon resonance effect resulted from the collective oscillations of surface electrons. In addition to this, noble metals deposited on the polymer can serve as centers for recombination of the photogenerated charge carriers, which causes a decrease in recombination rates of these charges in the photocatalyst. Among the metal nanoparticles, silver-based one has widely preferred due to high surface plasmons at a wavelength between 320 and 450 nm, which affects the reduction in the recombination rates of e- -h + pairs.

In this study, polyaniline-titanium dioxide nanoparticles composite material with the magnetic property which was decorated with silver nanoparticles polyaniline (MNPPANI-TiO2-AgNPs) were prepared through the chemical polymerization followed by the liquid impregnation method with additional reduction process to achieve an effective catalyst working under solar light. In order to reveal the effect of each component founded in the MNP-PANI-TiO2- AgNPs composite material on catalytic activity, bare PANI, magnetic nanoparticles added PANI (MNP-PANI) and TiO2 and magnetic nanoparticles added PANI (MNPPANI-TiO2) were prepared by applying the same procedure. After that, they were decorated with silver nanoparticles to form PANI-AgNPs, MNP-PANI-AgNPs, and TiO2-AgNPs. The characterization of prepared catalysts was performed by using Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Energy Dispersive X-ray Spectroscopy (EDX), X-ray Photoelectron Spectroscopy (XPS) and Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). The photocatalytic activities of the TiO2 nanoparticles (P25), bare PANI, MNP-PANI, MNP-PANI-TiO2, TiO2-AgNPs, PANI-AgNPs, MNP-PANI-AgNPs and MNP-PANITiO2-AgNPs were revealed in methylene blue (MB) degradation by using solar light exposure, respectively. According to the results, among them, MNP-PANI-TiO2- AgNPs composite material showed enhanced catalytic activity which provided 99 % degradation of dye in 40 min. So, highly efficient and stable photocatalyst which can be active in visible light was produced by adding AgNPs, MNP and TiO2 nanoparticles onto conducting polymer PANI by using green and fast methods.


İçindekiler



Açıklamalar



Haklar



Notlar



Kaynakça


Atıf Yapanlar

Gözat Sayfasına Dön

 

Sosyal Medya ve Araçlar

İstatistikler

  • Kayıt
    • Bu ay: 0
    • Toplam: 2555
  • Online
    • Ziyaretçi: 6
    • Üye: 0
    • Toplam: 6

Detaylı İstatistikler