Fabrication and synergistically enhanced photocatalytic activity of ternary kaolinite, TiO2, and Al2O3 (K65T30A5) nanocomposite for visible-light-induced degradation of methylene blue and remazol red dye

Nadira Parvin Lata; Md Sheum Hussain; Md Abdulla-Al-Mamun; Taslim Ur Rashid; Sayed Md Shamsuddin

doi:10.1016/j.heliyon.2024.e29255

Fabrication and synergistically enhanced photocatalytic activity of ternary kaolinite, TiO₂, and Al₂O₃ (K₆₅T₃₀A₅) nanocomposite for visible-light-induced degradation of methylene blue and remazol red dye

Heliyon. 2024 Apr 7;10(8):e29255. doi: 10.1016/j.heliyon.2024.e29255. eCollection 2024 Apr 30.

Authors

Nadira Parvin Lata¹, Md Sheum Hussain¹, Md Abdulla-Al-Mamun², Taslim Ur Rashid¹, Sayed Md Shamsuddin¹

Affiliations

¹ Department of Applied Chemistry and Chemical Engineering, Faculty of Engineering and Technology, University of Dhaka, Dhaka, 1000, Bangladesh.
² Institute of Leather Engineering and Technology, University of Dhaka, 44-50 Hazaribagh, Dhaka, 1209, Bangladesh.

Abstract

The ternary photocatalyst ((Al₂Si₂O₅ (OH)₄/TiO₂/Al₂O₃) composites (where w/w = 65, 30, and 5 wt%) denoted K₆₅T₃₀A₅ were successfully synthesized and examined for their efficiency in removing cationic (Methylene Blue, MB) and anionic (Remazol Red, RR) dye from aqueous medium under visible-light irradiation. A series of nanocomposites with varied wt% of kaolinite, TiO₂, and Al₂O₃ were prepared through sonication followed by calcination at 600 °C. X-ray diffraction (XRD) analysis confirmed the crystallinity of the synthesized materials and established their average crystal size to be 83.87 nm. The morphological structure, composite molecule, and surface properties of the resulting K₆₅T₃₀A₅ were characterized using FTIR, FE-SEM, and EDS analyses to confirm the successful fabrication of the nanocomposite. FTIR and EDS elemental mapping analyses confirmed the presence of Al, Si, Ti, and O elements in the nanocomposites. The composites exhibited photocatalytic behaviour across the UV-visible spectra, with values varying from the ultraviolet to the visible region with a sharp increase in reflectance at 510 nm. Near-complete degradation of MB (97.66 %) was achieved within 90 min at pH 9 and a 10 mg/L dye concentration, while RR removal reached 90.66 % within 120 min at pH 3.5 and the same dye concentration under visible light irradiation. The catalyst exhibited robust stability, retaining its efficiency by removing 85.09 % of MB and 80.21 % of RR dye after three reuse cycles. The composite catalyst discussed in this study emerges as a promising material for straightforward fabrication techniques, featuring a high percentage of kaolinite and proving to be a cost-effective solution for large-scale water and wastewater treatment processes.

Keywords: Al2O3; Kaolinite; Photodegradation; Recyclable photocatalysts; Ternary photocatalyst; TiO2.