Synthesis and characterization of MXene (TiCT)/Iron oxide composite for ultrasensitive electrochemical detection of hydrogen peroxide.

Due to the widespread usage of hydrogen peroxide (HO) in various consumer and industrial products (Examples: fuel cells and antibacterial agents), it became important to accurately detect HO concentration in environmental, medical and food samples. Herein, titanium carbide TiCT (MXene) was synthesized by using Ti, Al and C powders at high-temperature. Then, nanocrystalline iron oxide (α-FeO) was obtained from a single solid-phase method. Using TiCT and FeO powders, TiCT-FeO nanocomposite was prepared by ultrasonication. As-synthesized, TiCT-FeO composite had been characterized by UV-Visible (UV-Vis), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and Raman spectroscopy. The FeO nanoparticles (NPs) were decorated on the surface of TiCT as observed by high resolution scanning electron microscopy (HR-SEM) and high resolution transmission electron microscopy (HR-TEM). The TiCT nanosheets were formed with the average size of 400-500 nm. HR-SEM images of α-FeO showed that the coral-like particles with the average length ~5 μm were obtained The electrochemical properties of the individual (TiCT and α-FeO) and composite materials (TiCT-FeO) were investigated by cyclic voltammetry (CV). TiCT-FeO nanocomposite modified electrode had exhibited potent electro-catalytic activity for HO reduction by reducing the overpotential about 320 mV and a linear response was recorded from 10 nM to 1 μM HO. The optimization of various parameters such as material composition ratio, amount of catalyst, effects of pH, scan rate and interference effects with other biomolecules were carried out. In addition, the kinetic parameters such as rate constant, diffusion coefficient and the active surface area of the electrodes were calculated. Moreover, the TiCT-FeO composite modified electrode was used successfully to detect HO in food and urine samples. We believe that TiCT-FeO composite based materials could be used for the fabrication of non-enzymatic HO sensors for medical diagnosis, food safety and environmental monitoring applications.