Reduced graphene oxide/titanium carbide MXene nanocomposite‐modified electrode for electrochemical hemoglobin biosensor

Abstract In this work, reduced graphene oxide (rGO) and titanium carbide (Ti 3 C 2 T x ) nanocomposite was prepared by the self‐assembly method and used for electrode modification. The rGO‐Ti 3 C 2 T x nanocomposite was examined by scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, and X‐ray photoelectron spectroscopy. Then, an electrochemical hemoglobin (Hb) biosensor was prepared on the nanocomposite‐modified electrode and used for the determination of trichloroacetic acid (TCA) and hydrogen peroxide (H 2 O 2 ). Direct electrochemistry of Hb on the modified electrode was examined with the calculations of the electron transfer number, electron transfer coefficient, and the reaction rate constant. The presence of the rGO‐Ti 3 C 2 T x nanocomposite on the electrode can improve the effective surface area and biocompatibility of the electrode interface, obtaining a higher electron transfer rate. Furthermore, this electrochemical Hb biosensor exhibited excellent stability, reproducibility, and repeatability in TCA and H 2 O 2 analyses.