Reduced graphene oxide supported MXene based metal oxide ternary composite electrodes for non-enzymatic glucose sensor applications

Abstract Diagnosis and monitoring of glucose level in human blood has become a prime necessity to avoid health risk and to cater this, a sensor’s performance with wide linearity range and high sensitivity is required. This work reports the use of ternary composite viz. MG–Cu 2 O (rGO supported MXene sheet with Cu 2 O) for non-enzymatic sensing of glucose. It has been prepared by co-precipitation method and characterized with X-ray powder diffraction, Ultraviolet–visible absorption spectroscopy (UV–Vis), Raman spectroscopy, Field emission scanning electron microscopy, High resolution transmission electron microscopy and Selected area diffraction. These analyses show a cubic structure with spherical shaped Cu 2 O grown on the MG sheet. Further, the electrocatalytic activity was carried out with MG–Cu 2 O sensing element by cyclic voltammetry and chronoamperometry technique and compared with M–Cu 2 O (MXene with Cu 2 O) composite without graphene oxide. Of these, MG–Cu 2 O composite was having the high defect density with lower crystalline size of Cu 2 O, which might enhance the conductivity thereby increasing the electrocatalytic activity towards the oxidation of glucose as compared to M–Cu 2 O. The prepared MG–Cu 2 O composite shows a sensitivity of 126.6 µAmM −1 cm −2 with a wide linear range of 0.01to 30 mM, good selectivity, good stability over 30 days and shows a low Relative Standard Deviation (RSD) of 1.7% value towards the sensing of glucose level in human serum. Thus, the aforementioned finding indicates that the prepared sensing electrode is a well suitable candidate for the sensing of glucose level for real time applications.