A glassy carbon electrode modified with a film composed of cobalt oxide nanoparticles and graphene for electrochemical sensing of HO.

Li, Su-Juan; Du, Ji-Min; Zhang, Jia-Ping; Zhang, Meng-Jie; Chen, Jing

We have prepared a graphene-based hybrid nanomaterial by electrochemical deposition of cobalt oxide nanoparticles (CoONPs) on the surface of electrochemically reduced graphene oxide deposited on a glassy carbon electrode (GCE). Scanning electron microscopy and cyclic voltammetry were used to characterize the immobilized nanoparticles. Electrochemical determination of HO is demonstrated with the modified GCE at pH 7. Compared to GCEs modified with CoONPs or graphene sheets only, the new electrode displays larger oxidative current response to HO, probably due to the synergistic effects between the graphene sheets and the CoONPs. The sensor responds to HO with a sensitivity of 148.6 μA mM cm and a linear response range from 5 μM to 1 mM. The detection limit is 0.2 μM at a signal to noise ratio (SNR) of three. The method was successfully applied to the determination of HO in hydrogen peroxide samples. [Figure not available: see fulltext.]

CARBON electrodes; COBALT oxides; GRAPHENE; ELECTROCHEMISTRY; SIGNAL-to-noise ratio; HYDROGEN peroxide

Microchimica Acta, 2014, Vol 181, Issue 5/6, p631

0026-3672

Academic Journal

10.1007/s00604-014-1164-2