ZnO-NF/Graphene/Nafion as electrode platform for some pharmaceutical active ingredients sensor and energy storage applications

Abstract

This paper presents a simultaneous sensor for the detection of paracetamol (PAR)and ibuprofen (IBU). The sensor is based on a ZnO nanoflower/Graphene/Nafion coated glassy carbon electrode (ZnO NF/GR/Nafion/GCE) and a supercapacitor electrode with the same electrode component. The morphological characterisation of the prepared sensor and supercapacitor electrode was conducted via scanning electron microscopy (SEM), structural characterisation by X-ray diffraction spectroscopy, chemical characterisation by Fourier transform infrared spectroscopy (FT-IR) and Raman analysis. The electroactivity and selectivity of the ZnO NF/GR/Nafion sensor platform towards IBU and PAR were simultaneously investigated by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS). Electrochemical tests of the sensor were conducted in a three-electrode electrochemical system in 0.1 M B-R buffer (pH 4.0). The linear ranges of the ZnO NF/GR/Nafion sensor towards PAR and IBU were determined in the range of 1.0 and 1000.0 μM. The detection limits for PAR and IBU were calculated as 0.28 µM and 0.31 µM, respectively. In real sample analyses, the efficiency of the investigated sensor in different drug formulations was found to respond to PAR and IBU with high recovery (99.05 % and 103.35 %). The supercapacitor electrode was prepared by changing the same electrode component, amounts and ratios of the components. The performance of the supercapacitor electrode was investigated in the potential range from 0 V to 1.2 V in PVA-H₂SO₄ electrolyte. The supercapacitor electrode demonstrated a specific capacitance of 488.1 F g⁻¹ at a scan rate of 5 mV s⁻¹ and a capacitance value of 405.5 F g⁻¹ at a current density of 7 mA.cm⁻². In this study, the ZnO NF/GR/Nafion/GCE hybrid electrode produced is used as both sensor and supercapacitor electrode material and operates in dual mode. The production method is cheap and simple, and no additional modifications are needed in the production of electrode components. In this study, for the first time in the literature, the electrode material with ZnO NF/GR/Nafion/GCE component is used in the analysis of some pharmaceutical active ingredients and in supercapacitor applications.