A novel sensor based on Ti₃C₂ MXene/Co₃O₄/carbon nanofibers composite for the sensitive detection of 4-aminophenol

A novel, sensitive Ti₃C₂ MXene/Co₃O₄/carbon nanofibers (Ti₃C₂ MXene/Co₃O₄/CNFs) composite was synthesized via a HF exfoliating Ti₃AlC₂ strategy, followed by doping Co₃O₄ and Ti₃C₂ MXene into the CNFs via a combination electrospinning and thermal annealing process. Ti₃C₂ MXene/Co₃O₄/CNFs composite exhibits higher catalytic effect, conductivity, chemical stability, and electrochemical performance than Co₃O₄ and Ti₃C₂ MXene in electrochemical impedance, differential pulse stripping voltammetry, chronocoulometry, and cyclic voltammetry tests. This Ti₃C₂ MXene/Co₃O₄/CNFs hybrid modified electrode provides fast analysis of 4-aminophenol (4-AP) with ultrahigh sensitivity, enhanced reproducibility and strong anti-interference capability. Furthermore, the level of 4-AP was quantified by this electrode with a wide linear range from 0.5 to 150 μM (R² > 0.99) and a low detection limit about 0.018 μM was achieved. Finally, the fabricated electrode was used for fast and sensitive analysis of 4-AP spiked in tap water and blood serum samples. This work presents the new Ti₃C₂ MXene/Co₃O₄/CNFs electrode provides a platform for 4-AP monitoring and has the advantages of high selectivity, accuracy, simplicity, and rapid analysis.