Optimizing the photocatalytic performance of SnO2 nanoparticles for methylene blue removal with variation in calcination temperatures

Abstract

In recent years, numerous studies have been conducted to combine tin oxide (SnO2) with various semiconductor materials to boost its photocatalytic efficiency for water waste treatment, with minimal emphasis placed on intensifying the intrinsic capabilities of pure SnO2. The primary objective of this study is to enhance the photocatalytic efficiency of pure SnO2 nanoparticles (NPs) by modifying their morphology, structural, and optical properties. The SnO2 NPs were synthesized using precipitation method, followed by a calcination process at varying temperatures (non-calcined, 300 °C, and 500 °C). The changes in properties of SnO2 NPs were investigated utilizing X-ray diffraction (XRD), scanning electron microscopy (SEM), particle size analysis (PSA), Brunauer-Emmett-Teller (BET), and ultraviolet-visible (UV-Vis) spectroscopy. The results indicated that elevating the calcination temperature up to 500 °C resulted in an increase in both the average crystallite size (up to 10.50 nm) and crystallinity (up to 85.28 %). However, the highest photocatalytic efficiency for methylene blue degradation of 84.78 % was obtained from the SnO2 NPs calcined at 300 °C sample exhibiting the largest surface area of 83.97 m2g-1. This study affirms that the specific surface area of SnO2 NPs is a critical factor in their efficacy for degrading dye-contaminated water waste.