A glassy carbon electrode modified with ordered nanoporous Co3O4 for non-enzymatic sensing of glucose

Ordered porous Co3O4 materials with pore sizes of 5 nm (Co3O4–5), 20 nm (Co3O4–20), and 70 nm (Co3O4–70) have been synthesized via a hard-template method and were studied as catalysts to bring insight into non-enzymatic electrochemical sensing of glucose. A glassy carbon electrode modified with Co3O4–70 responds more quickly and sensitively to glucose than those modified with Co3O4–5 or Co3O4–20. The sensor based on the use of Co3O4–70 and operated at a working voltage of 0.6 V (vs. Ag/AgCl) in 0.1 M NaOH solution shows a lower detection limit of 0.025 μM, good repeatability and high selectivity over ascorbic acid, uric acid, dopamine, and KCl. These results suggest that ordered porous Co3O4 is a promising material for quantitative electrochemical determination of glucose, and that the pore size has a strong effect on performance.