An efficient eco advanced oxidation process for phenol mineralization using a 2D/3D nanocomposite photocatalyst and...

Nanocomposites (CNTi) with different mass ratios of carbon nitride (C₃N₄) and TiO₂ nanoparticles were prepared hydrothermally. Different characterization techniques were used including X-ray diffraction (XRD), UV-Vis diffuse reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS), transmission electron spectroscopy (TEM) and Brunauer-Emmett-Teller (BET). UV-Vis DRS demonstrated that the CNTi nanocomposites exhibited absorption in the visible light range. A sun light - simulated photoexcitation source was used to study the kinetics of phenol degradation and its intermediates in presence of the as-prepared nanocomposite photocatalysts. These results were compared with studies when TiO₂ nanoparticles were used in the presence and absence of H₂O₂ and/or O₃. The photodegradation of phenol was evaluated spectrophotometrically and using the total organic carbon (TOC) measurements. It was observed that the photocatalytic activity of the CNTi nanocomposites was significantly higher than that of TiO₂ nanoparticles. Additionally, spectrophotometry and TOC analyses confirmed that degraded phenol was completely mineralized to CO₂ and H₂O with the use of CNTi nanocomposites, which was not the case for TiO₂ where several intermediates were formed. Furthermore, when H₂O₂ and O₃ were simultaneously present, the 0.1% g-C₃N₄/TiO₂ nanocomposite showed the highest phenol degradation rate and the degradation percentage was greater than 91.4% within 30 min.