Opto-Thermal Analysis of SnO2 and SnO2/Al2O3 Composites: Insights for Enhanced Wastewater Treatment

Water pollution remains a pressing environmental issue, necessitating the development of advanced photocatalysts for effective wastewater treatment. This research synthesized pure SnO2 and SnO2/Al2O3 core-shell composite photocatalysts via a simple and cost-efficient sol-gel method. The thermoluminescence (TL) glow curves were recorded after 15 minutes of X-ray irradiation and analyzed using the initial rise method, peak shape analysis, and curve fitting techniques. These analyses revealed the presence of multiple trapping sites in SnO2/Al2O3 composite, providing valuable insights into charge carrier dynamics and material properties essential for photocatalytic and radiation dosimetry applications. The photocatalytic performance of the materials was assessed by monitoring the degradation of methyl orange (MO) under UV irradiation of 254 nm wavelength. The SnO2/Al2O3 composite exhibited significantly improved photocatalytic efficiency, achieving 80.26% MO degradation within 1 hour with a rate constant of 0.03174 min⁻¹, surpassing the performance of pure SnO2. This enhanced activity is attributed to the localized surface plasmon resonance (LSPR) and abundant trapping sites of the composite, which effectively capture photogenerated charge carriers, reduce recombination rates, and maintain a higher concentration of reactive species such as hydroxyl radicals and superoxide anions. Moreover, the TL glow curve analysis highlights the potential of the SnO2/Al2O3 composite as a reliable material for radiation dosimetry, suitable for applications in medical, environmental, and industrial fields requiring accurate radiation measurements. These results underscore the dual-functional nature of the SnO2/Al2O3 composite, demonstrating its efficacy as both an efficient photocatalyst for wastewater treatment and a promising candidate for radiation monitoring.