Electrochemically Deposited Cu(II)/Cu(I) Oxide Heterostructure as Highly Sensitive Platform for Electrochemical Detection of Glucose and Methanol

Detection of glucose level and in human body is very essential in many ways. Besides glucose, methanol also plays crucial role in human physiology as it can influence human nervous system. So, detection of any imbalance in methanol level is also crucial. For this purpose, in this work, CuO/Cu₂O bulk heterostructures were electrochemically deposited in the form of thin films on ITO-coated glass substrates using cyclic voltammetry and amperometrically. The deposited films were characterized using X-ray diffraction technique (XRD), field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM) and UV–Vis spectroscopy. The electrochemical attributes of the deposited films towards glucose and methanol sensing were studied through cyclic voltammetry (CV), amperometric i-t and electrochemical impedance spectroscopy (EIS). From the linear fit plot, the sensitivity was found to be 237.7 µA µM⁻¹ cm⁻² with LoD (limit of detection) of 19.8 µM and up to 1.2 mM concentration of glucose. Further, for methanol, both LoD and sensitivity values were found to be 0.007 µM and 0.016 µA/µM.cm², respectively. The results are quite promising for the deposited material for its possible real-life applications as sensing platform for the electrochemical D-glucose and methanol detections.