Colorimetric Detection of Multiple Phenols Based on Multifunctional Fe₃ O₄ /SnS₂ Composites

Phenols pose a great threat to human and environment due to their high toxicity and low bio-degradability. Therefore, the development of a rapid and sensitive detection method for multiple phenols is of great importance. Here, a colorimetric detection method based on Fe₃ O₄ /SnS₂ composites was established for the detection and discrimination of ten phenols for the first time. The results demonstrated that the incorporation of the photo catalyst SnS₂ significantly improved the peroxidase-like activity of Fe₃ O₄ , leading to an enhancing efficiency of the colorimetric detection method. The developed method was capable of detecting phenol within a concentration range of 0.5-2000 μM, with detection limit as low as 0.06 μM. This method was successfully applied to detect total phenols in samples obtained from two sewage treatment plants and seawater. Furthermore, by employing principal component analysis, the established colorimetric method enabled the simultaneous discrimination of all ten phenols. The performance was further evaluated by accurately identifying binary or ternary mixtures of phenols, and even identifying the type of phenol in 10 unknown samples containing one of the ten phenols. These findings highlight the potential of the Fe₃ O₄ /SnS₂ composite as a promising candidate for the simultaneous detection of multiple phenols in liquid samples.