Hierarchical multi-layered molybdenum carbide encapsulated oxidized carbon nanofiber for selective electrochemical detection of antimicrobial agents: inter-connected path in multi-layered structure for efficient electron transfer

Abstract

Metal carbides are an emerging class of electrode materials for various electrochemical applications. Herein, we have synthesized the molybdenum carbide (Mo₂C) hexagons via a template assisted method. Subsequently, the Mo₂C hexagons were integrated with functionalized carbon nanofiber (f-CNF) via the ultra-sonication method. The prepared Mo₂C and Mo₂C/f-CNF composites were analyzed using different techniques such as XRD, RAMAN, HR-TEM, and ESCA. The HR-TEM images of Mo₂/C/f-CNF composite evidently proved that the Mo₂/C hexagons are well integrated on surface of f-CNF along with a connection part for efficient electron transfer from Mo₂C to f-CNF structure. Due to its excellent electrochemical properties, the proposed Mo₂C/f-CNF nanocomposite modified GCE was developed as an efficient electrode for the electrochemical detection of metronidazole (MTZ). As expected, Mo₂C/f-CNF/GCE achieved the ultra-low detection limit of 0.002 μM and the linear range of 0.04–647.7 μM in sensing of MTZ. Mo₂C/f-CNF/GCE was successfully for real time detection in human urine samples. All the electrochemical results clearly proved that the Mo₂C/f-CNF composite is an effective electrode for detection of MTZ.