Influence of pH on the Sol-Gel Synthesis of TiO2 Nanoparticles: Structural, Morphological, and Surface Properties

Öz

This study focused on the effects of acidic pH on the precursor solution, impacting the structural, morphological, and surface features of TiO2 nanoparticles. Therefore, TiO2 nanoparticles at three different acidic pH levels (pH=2, pH=4, and pH=6) using a sol-gel process from a titanium (IV) isopropoxide (TIP) precursor were synthesized. The synthesized TiO2 nanoparticles at three different pH levels were systematically characterized by FTIR, Raman spectroscopy, XRD, SEM, XPS, and BET analytical techniques. The obtained TiO2 nanoparticles at pH=2 (TiO2-2) exhibited a multi-phase pattern of dominant anatase and minor rutile, while TiO2 specimens prepared at pH=4 (TiO2-4) and pH=6 (TiO2-6) consisted only of a single anatase phase. The crystallite particle sizes of TiO2 specimens decreased as the pH level increased. The TiO2-4 and TiO2-6 specimens revealed smoother and agglomerated surface morphologies compared to the TiO2-2 specimen. All the isotherm curves were Type IV, and the BET surface areas of TiO2-2, TiO2-4, and TiO2-6 specimens were 50 m2/g, 54 m2/g, and 59 m2/g.

Anahtar Kelimeler

• Catalyst
• pH effect
• Sol-gel
• TiO2 particles
• Water pollution

pH Değişiminin TiO2 Nano Taneciklerinin Sol-Jel Sentezi Üzerine Olan Etkisi: Yapısal, Morfolojik ve Yüzey Özellikleri

Öz

Çalışma, TiO2 nano taneciklerinin yapısal, morfolojik ve yüzey özelliklerini etkileyen farklı asidik pH değerlerinde hazırlanan çözelti etkisi incelenmiştir. Bu nedenle, titanyum (IV) izopropoksit (TIP) ile sol-jel işlemi kullanılarak üç farklı asidik pH değerinde (pH=2, pH=4 ve pH=6) TiO2 nano taneciklerisentezlenmiştir. Üç farklı pH değerinde hazırlanan TiO2 nanotanecikleri FTIR, Raman spektroskopisi, XRD, SEM, XPS ve BET analitik yöntemleri kullanılarak sistematik bir şekilde karakterize edilmiştir. pH=2'de elde edilen TiO2 nano tanecikleri (TiO2-2) başlıca kristal fazı olarak anatazdan ve az miktarda rutilden oluşan çoklu faz içermekte olup, pH=4 (TiO2-4) ve pH=6 (TiO2-6) değerlerinde hazırlanan TiO2 örnekleri ise sadece anataz fazından oluşmaktadır. TiO2 örneklerinin kristalit tanecik boyutlarının pH değeri arttıkça azaldığı gözlenmiştir. TiO2-4 ve TiO2-6 numuneleri, TiO2-2 örneğine kıyasla daha düz ve kümelenmiş taneciklerden oluşmuş bir yüzey morfolojisine sahiptir. Örneklerin izoterm eğrileri Tip IV izotermine uymaktadırlar. TiO2-2, TiO2-4 ve TiO2-6 örneklerinin BET yüzey alanları sırasıyla 50 m2/g, 54 m2/g ve 59 m2/g olarak bulunmuştur.

Anahtar Kelimeler

• Katalizör
• pH etkisi
• Sol-jel
• Su kirliliği
• TiO2 parçacıkları

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