Excellent visible-light photocatalytic activity towards the degradation of tetracycline antibiotic and electrochemical sensing of hydrazine by SnO₂–CdS nanostructures

The present study investigated a tin oxide/cadmium sulfide (SnO₂–CdS) nanostructure for enhancing the photocatalytic efficiency of CdS nanoparticles. Herein, the desired nanostructure was fabricated through a straightforward and cost-effective approach. The physicochemical properties of the fabricated nanostructure were analyzed by various characterization techniques. The SnO₂–CdS shows an excellent band-gap of 2.14 eV, a high surface area of 29 m²/g, and favorable photoluminescence properties. The examination of the degradation capabilities of SnO₂–CdS nanostructures (SOCdS) with visible light was conducted using tetracycline hydrochloride (TC), methylene blue (MB), and Congo red (CR) as models of antibiotic and dye pollutants. The photocatalyst possessed a TC removal efficiency of 94.5 ± 0.02% in 60 minutes under visible-light irradiation with over 60 ± 0.06% adsorption of TC under equilibrium conditions. Further, the photocatalysts exhibited excellent performance for MB and CR degradation with degradation effectiveness of 99.08 ± 0.01% in 120 min and 83 ± 0.06% in 40 min, respectively. In addition, the glassy carbon electrode (GCE) was modified with SOCdS (SOCdS/GCE) and was employed for the efficient and precise detection of hydrazine at room temperature. The SOCdS/GCE showed first-rate response for the recognition of hydrazine: CV: LOD of 0.18 μM, 8 μM–50 μM linear range, and 25.7 μA μM⁻¹ cm⁻² of sensitivity; and LSV: LOD of 0.19 μM, 5 μM–50 μM linear range, and 23.6 μA μM⁻¹ cm⁻² of sensitivity. Results suggest that the SnO₂–CdS nanostructure showed excellent photocatalytic activity than bare-CdS NPs and has the ability to detect the analyte viz. hydrazine. The role of CdS nanoparticles is interesting to enhance the photocatalytic and electrochemical properties. We report a straightforward and cost-effective fabrication approach for SnO₂–CdS nanostructure and provide a robust platform for the utilization of chalcogenides-based systems for environmental remediation and detection of hazardous chemicals.