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

Abstract

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.