Tweaking the electrocatalytic efficiency of sonochemically synthesized Bi2S3 nanorods through decoration with f-MWCNTs: A selective on-site detection of METOL in environmental samples

In this study, we have established a highly conductive Bi₂S₃/f-MWCNT nanocomposite through a sonochemical approach using a probe sonicator (100 W, 25 kHz), which functions as an effective electrochemical probe for the detection of 4-(methylamino)phenol sulfate or METOL (MET) in environmental water samples. MET, a widely used chemical in hair dyes and the photographic industries, poses significant environmental concerns when released into water systems, contributing to water pollution and ecological disruption. Comprehensive characterization techniques confirmed the structural integrity and enhanced electrochemical properties of the Bi₂S₃/f-MWCNT nanocomposite. The as-prepared Bi₂S₃/f-MWCNT demonstrated exceptional sensing capabilities, with a phenomenal limit of detection of 6.52 nM within a linear range of 0.01 to 2100 μM, and exhibited a sensitivity of 10. 514 μA μM^-1 cm^-2. The practical applicability of the sensor was validated through its successful use in detecting MET in real-world environmental samples, such as river water, pond water, wastewater, and tap water. Additionally, the integration of the Bi₂S₃/f-MWCNT sensor with a smart potentiostat provides a powerful platform for on-site monitoring of water quality. This work offers a promising approach for the detection of industrial pollutants and provides a potential solution for advancing environmental sustainability.