Open Access Peer-reviewed Research Article

Green Synthesis of SnO₂/Bentonite Nanocomposite Using Murraya koenigii Leaf Extract for Photocatalytic Degradation of Rhodamine B Dye and Carbofuran Pesticide in Aqueous Solution

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Submitted   Jun 9, 2026
Published   Aug 19, 2026
Issue    Vol 7 No 1 (2026)
DOI   10.25082/HE.2026.01.004

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Samar Jahan
Department of Chemistry, Faculty of Science, University of Agriculture, Faisalabad, Pakistan
Raziya Nadeem
Department of Chemistry, Faculty of Science, University of Agriculture, Faisalabad, Pakistan
Noor Zulfiqar corresponding author
Department of Chemistry, Faculty of Science, University of Agriculture, Faisalabad, Pakistan
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Abstract

Water contamination by synthetic dyes and pesticides is a major environmental concern because of their persistence, toxicity, and adverse effects on aquatic ecosystems and human health. The present study focused on the green synthesis of SnO₂ nanoparticles and the preparation of a SnO₂/bentonite nanocomposite (SBT-NC) using Murraya koenigii leaf extract and its application for the photocatalytic degradation of Rhodamine B (RhB) dye and Carbofuran (CBF) pesticide in aqueous solutions. Bentonite was used as a supporting material to improve the adsorption capacity, surface area, and dispersion of SnO₂ nanoparticles. The synthesized materials were characterized using UV–visible spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and Fourier-transform infrared spectroscopy (FTIR). The characterization results confirmed the successful formation and incorporation of SnO₂ nanoparticles onto the bentonite matrix. The effects of important experimental parameters, including solution pH, initial pollutant concentration, contact time, and catalyst dosage, were investigated under light irradiation. The SBT-NC showed considerably higher photocatalytic degradation efficiency than pure bentonite and SnO₂ nanoparticles. Under optimized conditions, the degradation efficiency of Rhodamine B reached approximately 92–94%, while Carbofuran degradation reached approximately 90–91%. The optimum conditions included alkaline pH for Rhodamine B and acidic pH for Carbofuran, with a catalyst dosage of approximately 0.1 g and a reaction time of about 90–120 min. The enhanced performance of SBT-NC was attributed to the synergistic effect of the adsorption properties of bentonite and the photocatalytic activity of SnO₂, which provided additional active sites and promoted the formation of reactive oxygen species. Kinetic analysis indicated that the degradation of both pollutants was generally better described by the pseudo-first-order kinetic model. Overall, the green-synthesized SnO₂/bentonite nanocomposite demonstrated strong potential as an efficient, economical, and environmentally friendly photocatalyst for the removal of organic pollutants from contaminated water.

Keywords
SnO₂/bentonite nanocomposite, green synthesis, Murraya koenigii, photocatalytic degradation, Wastewater treatment, SnO₂ nanoparticles, organic pollutants, advanced oxidation process

Article Details

How to Cite
Jahan, S., Nadeem, R., & Zulfiqar, N. (2026). Green Synthesis of SnO₂/Bentonite Nanocomposite Using Murraya koenigii Leaf Extract for Photocatalytic Degradation of Rhodamine B Dye and Carbofuran Pesticide in Aqueous Solution. Health and Environment, 7(1), 328-344. https://doi.org/10.25082/HE.2026.01.004
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This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

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