The Multifunctionalised TiO2/Ag/Cellulose Acetate Photocatalyst with Enhanced Photodegradation and Antibacterial Activities

• Main Author: Feniellia Diwvya Anak, Kutiang
• Format: Thesis
• Language: English; English; English
• Published: Universiti Malaysia Sarawak 2023
• Subjects: QD Chemistry
• Online Access: http://ir.unimas.my/id/eprint/43252/3/Feniellia%20Diwvya_dsva.pdf; http://ir.unimas.my/id/eprint/43252/4/Thesis%20MSc._Feniellia%20Diwvya%20-24%20page.pdf; http://ir.unimas.my/id/eprint/43252/5/Thesis%20MSc._Feniellia%20Diwvya.ftext.pdf; http://ir.unimas.my/id/eprint/43252/

Titanium dioxide, TiO2 photocatalyst has been greatly employed in the photocatalytic treatment of wastewater due to its excellent properties. The combined effects of doping and the inclusion of support material such as cellulose acetate (CA) can enhance the photocatalytic efficiency of TiO2 photocatalysts. In this study, TiO2 was synthesised via a green solvent template, ionic liquid, IL (1-butylimidazolium acetate) to produce high surface area photocatalyst and combined with silver (Ag) dopant to improve its photocatalytic performance in visible light. CA was added as support in the photocatalyst for the degradation of multiple dyes namely methylene blue (MB), methyl orange (MO), and rhodamine B (RhB). This study investigated the effect of different volumes of IL (0.5 mL – 5.0 mL) used in the synthesis of TiO2 via the sol-gel method, the effect of different Ag concentrations (0.5 wt% - 5.0 wt%) and CA concentrations (0.5 wt% - 5 wt%) on the photocatalytic performance of TiO2/Ag. The photocatalytic ability of TiO2-1/Ag 2 %/CA 0.5% photocatalyst under various operating parameters such as photocatalyst dosage, initial dye concentration, initial pH and effect of radical scavenger was investigated. The recyclability of TiO2-1/Ag 2 %/CA 0.5% was also determined. The characterisation of TiO2- 1/Ag 2 %/CA 0.5% photocatalyst via X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Energy Dispersive X-Ray (EDX), Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM) analysis revealed the presence of Ag and CA on the surface of TiO2. Brunauer Emmett Teller (BET) surface area analysis has shown that the inclusion of IL in the synthesis greatly increased the surface area of TiO2 from 130.9 m2/g to 174.8 m2/g. Based on the preliminary experiments, 1.0 mL of IL, 0.5 wt% of Ag and 2.0 wt% of CA contributed to the highest photocatalytic degradation of TiO2/Ag/CA photocatalyst and were chosen for further studies. TiO2/Ag/CA (IL: 3 mL, Ag:2 wt% & CA: 0.5%) showed the highest MB dye removal in individual and mixed dye conditions (MB, MO and RhB) after 120 min of treatment time upon UVA irradiation (λ = 365 nm) under solution with pH 7.4. The antibacterial activity of TiO2-1/Ag 2 %/CA 0.5% investigated via disc diffusion method against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacteria demonstrated inhibition zones, indicating antibacterial effectiveness of TiO2-1/Ag 2 %/CA 0.5%. As wastewater treatment requires the removal of chemical pollutants and unwanted biological components, TiO2-1/Ag 2 %/CA 0.5% photocatalyst depicted in this study can be a promising degradative tool to meet this dual goal with high efficiency.