Electrochemical Investigation of Caffeine by Cerium Oxide Nanoparticle Modified Carbon Paste Electrode

Abstract

In the present study, facile electrochemical sensor built on carbon paste electrode modified with as synthesized CeO2 nanoparticles (Cerium Oxide Modified Carbon Paste Electrode-CMCPE) for electrochemical detection of caffeine is reported. The CeO2 nanoparticles are in cubic phase as shown by XRD. The particles are spherical and are seems to be agglomerated as revealed by SEM and TEM. The formation of the CeO2 was further confirmed by characteristic stretching frequencies below 500 cm−1 in FT-IR analysis. The properties of the modified electrode were investigated by cyclic voltammetry (CV) and Differential Pulse Voltammeter (DPV). The DPV experiments reveal that CMCPE shows high sensitivity for the detection of caffeine in the range 5–80 μM and the detection limit is 0.036 μM (S/N = 3). The CMCPE shows high catalytic activity, good reproducibility and sensitivity for the electrochemical detection of caffeine.