Facile Synthesis of MnCo ₂ O ₄ ‐MWCNTs Nanocomposites for Sensitive Determination of Sulfamethazine in Water Samples

Transition metal oxide nanoparticles have garnered considerable attention due to their superior electrochemical catalytic performance and low cost, making them pivotal in the design of sensitive electrochemical sensors. In this report, a simple hydrothermal approach for preparing a hybrid nanomaterial is presented that combines manganese cobalt oxide (MnCo ₂ O ₄ ) and multiwalled carbon nanotubes (MWCNTs). The resulting MnCo ₂ O ₄ ‐MWCNTs hybrids exhibit high specific surface area and demonstrate excellent electrochemical catalytic performance when fixed onto a glassy carbon electrode (GCE) to form a chemically modified electrode. The MnCo ₂ O ₄ ‐MWCNTs/GCE sensor shows exceptional analytical performance in detecting sulfamethazine (SMZ). Owing to the high specific surface area and synergistic catalytic performance of the hybrids, the sensor achieves a remarkable limit of detection of 0.03 μM for SMZ while maintaining excellent selectivity and stability. Moreover, the proposed sensor was applied to determine SMZ levels in aquaculture water. Good recovery and stable relative standard deviation are obtained during the standard addition procedure, implying the perfect analytical performance of the proposed sensor.