CeO₂ quantum dots modified electrode for detecting hydrogen peroxide

This study describes the fabrication of a sensitive modified electrode for detecting hydrogen peroxide. The glassy carbon surface was modified with a composite containing CeO₂ quantum dots and carbon sheets. The ultra-small grain size of nanoparticle endows the electrode with excellent electrocatalytic activity. As a result, the electrode shows electrocatalytic reduction activity toward H₂O₂ at a potential of −0.5 V. The CeO₂ quantum dots sensor shows a satisfactory performance for detecting hydrogen peroxide with a linear range of 2 ppm–1000 ppm, and a limit of detection (LOD) of 900 ppb. These findings show that CeO₂ quantum dots have a great potential for applications in electrochemical sensing.