Sulfur-doped graphitic C3N4 decorated on cauliflower-like CaMoO4: An efficient electrocatalyst for electrochemical detection of carcinogenic organic pollutant (metol)
This study introduces a highly active electrochemical sensor developed by decorating sulfur-doped graphitic carbon nitride (S-C3N4) onto cauliflower-like calcium molybdate (CaMoO4). This novel composite serves as an efficient electrocatalyst designed for the ultra-sensitive and selective detection of metol, a toxic and carcinogenic organic pollutant commonly discharged from photographic and hair dye industries. Characterized via comprehensive microscopic and spectroscopic techniques, the sensor demonstrates superior performance with a very low detection limit of 0.002 µM and a broad linear detection range. It offers a robust, cost-effective platform for real-time environmental water quality monitoring.
Graphical abstract.
Technology Overview
The S-C3N4/CaMoO4 composite is fabricated via an eco-friendly ultrasonication process. Integrating the folded, highly conductive morphology of S-C3N4 with the abundant active sites of cauliflower-like CaMoO4 induces a powerful synergistic effect. This architecture significantly accelerates electron transportation and reduces charge-transfer resistance. Metol is quantitatively detected using differential pulse voltammetry (DPV) through a reversible two-electron, two-proton redox reaction.
Applications & Benefits
The S-C3N4/CaMoO4 composite sensor is highly suited for environmental monitoring, water safety assessment, and testing diverse natural water resources, including tap, lake, and river water. It delivers ultra-sensitive (3.93 µA µM⁻¹ cm⁻² sensitivity) and rapid detection with an exceptionally low detection limit of 0.002 µM. Furthermore, the sensor offers outstanding selectivity against common interferences, high recovery rates, and excellent reproducibility, making it an ideal choice for practical, in-field use.
Abstract：
Environmental monitoring of organic pollutants in water sources is crucial for protecting human health and ecosystem sustainability. Herein, we develop a highly active electrocatalyst composite consisting of cauliflower-like calcium molybdate (CaMoO4) decorated with sulfur-doped graphitic carbon nitride (S–C3N4) for the ultrasensitive electrochemical detection of organic pollutant metol. Various microscopic and spectroscopic techniques were employed to analyze the structural and compositional characteristics of the S–C3N4/CaMoO4 composite. The electrochemical sensor with the optimized S–C3N4/CaMoO4 composite demonstrates a high sensitivity of 3.93 μA μM−1 cm−2 and a low limit of detection of 0.002 μM in a wide linear range (0.01–134 μM) by the DPV method. The excellent performance can be attributed to their high conductivity, high surface area, swift electron transportation, favorable active sites, and synergistic effect. Besides, the proposed electrochemical sensor exhibits good reproducibility and remarkable selectivity in the presence of various potential interference compounds in water sources. Its practical applicability for environmental monitoring is verified by quantifying metol in tap water, lake water, and river water. This work highlights the feasibility of rapid and robust electrochemical sensing of the organic pollutant metol at low concentrations and validates its suitability for the in-field applications.
Sulfur-doped graphitic C3N4 decorated on cauliflower-like CaMoO4: An efficient electrocatalyst for electrochemical detection of carcinogenic organic pollutant (metol)
Author：Ganesan Selvaganapathy, Kokulnathan Thangavelu, Wang Tzyy-Jiann, Palaniappan Arunkumar
Year：2024
Source publication： Chemosphere, Volume 369, December 2024, 143815
Subfield Highest percentage： 99% Public Health, Environmental and Occupational Health #7/687