Structure and electrochemical detection of xenobiotic micro-pollutant hydroquinone using CeO2 nanocrystals

Abstract

In this study, cerium oxide nanocrystals (CeO2 NCs) were synthesized by simple and cost effective precipitation method. The structural properties of the obtained CeO2 NCs were characterized by means of X-ray diffraction (XRD) with Rietveld refinement analysis, Transmission electron microscopy (TEM). X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray spectroscopy (EDX) confirms the presence of CeO2 NCs. The structural properties confirmed the presence of cubic fluorite-type structure which is in agreement with the respective Inorganic Crystal Structure Database (ICSD) no. 156250. The hydroquinone (HQ) sensing of CeO2 NCs/carbon paper (CP) modified electrode in 0.1 M phosphate buffer solution (pH = 7) was characterized using a cyclic voltammetric (CV) electrochemical technique. The CV curve exhibited redox peaks with a detection limit of 0.111 mM and the linear ranges (0.03-0.8 mM) with a sensitivity of 2.443 mA mM(-1) cm(-2) for HQ detection. Our results indicate that CeO2 NCs modified on CP holds as a promising candidate for the electrochemical detection of toxic HQ.