MoS₂/Tungsten Carbide Nanocomposite as Disposable Electrochemical Strips for the Detection of Hazardous 4-Nitroaniline

In this investigation, we have developed a highly efficient and robust electrode nanocomposite tailored for the electrochemical sensing of 4-nitroaniline (4-NA), a hazardous pollutant. We synthesized a three-dimensional flower-like molybdenum disulfide (MoS2) embedded tungsten carbide (WC) nanocomposite utilizing a straightforward ultrasonic technique. This nanocomposite was integrated onto a screen-printed carbon electrode (SPCE) and optimized for electrochemical detection. Under these optimal conditions, the MoS2/WC nanocomposite demonstrates remarkable analytical performance for 4-NA detection, characterized by two distinguishable linear concentration ranges of 2–458 μM and 458–1288 μM. The sensor exhibits a sensitivity of 1.38 μA μM–1 cm–2 and a low detection limit of 0.034 μM, highlighting its potential for effective real-time monitoring of 4-NA in environmental samples. The enhanced performance of the MoS2/WC/SPCE can be attributed to the synergistic effect of individual MoS2 (large specific surface area, unique structural characteristics) and WC (high conductivity, increased number of active surface sites, and high stability). The MoS2/WC nanocomposite demonstrates superior electrocatalytic performance for the reduction of 4-NA in neutral electrolytes compared to previously reported electrocatalysts. Moreover, the MoS2/WC-modified SPCE shows remarkable selectivity and good reproducibility in detecting 4-NA. This innovative approach holds significant promise for advancing environmental application outcomes for real-time sensing applications.