Preparation of co-Co₃ O₄ /carbon nanotube/carbon foam for glucose sensor

Co-Co₃ O₄ /carbon nanotube/carbon foam (Co-Co₃ O₄ /CNT/CF) nanocomposites were prepared by soaking melamine foam into a solution of Co(NO₃ )₂ ·6H₂ O, followed by calcination in N₂ and air in sequence. The obtained Co-Co₃ O₄ /CNT/CF nanocomposites were characterized with scanning electron microscopy and cyclic voltammetry. It was found that Co₃ O₄ nanoparticles were grown on the external of CF successfully, while CNTs were grown on the surfaces of CF in a large amount, which further improved the electrical conductivity of the. The prepared Co-Co₃ O₄ /CNT/CF nanocomposites were then used to construct nonenzymatic sensor to detect glucose in alkaline solution. The sensor showed detection range from 1.2 μM to 2.29 mM with a detection limit of 0.4 μM (S/N =3) and a high sensitivity of 637.5 μA^-1 cm^-2 . The developed sensor also showed an instant response, favorable reproducibility, and high selectivity. The results attest that Co-Co₃ O₄ /CNT/CF composites have great potential in the development of nonenzymatic sensors for glucose.