MOF derived Co3O4/N-doped carbon nanotubes hybrids as efficient catalysts for sensitive detection of H2O2 and glucose

Developing enzyme-free sensors with high sensitivity and selectivity for H₂O₂ and glucose is highly desirable for biological science. Especially, it is attractive to exploit noble-metal-free nanomaterials with large surface area and good conductivity as highly active and selective catalysts for molecular detection in enzyme-free sensors. Herein, we successfully fabricate hollow frameworks of Co₃O₄/N-doped carbon nanotubes (Co₃O₄/NCNTs) hybrids by the pyrolysis of metal-organic frameworks followed by calcination in the air. The as-prepared novel hollow Co₃O₄/NCNTs hybrids exhibit excellent electrochemical performance for H₂O₂ reduction in neutral solutions and glucose oxidation in alkaline solutions. As sensor electrode, the Co₃O₄/NCNTs show excellent non-enzymatic sensing ability towards H₂O₂ response with a sensitivity of 87.40 μA (mmol/L)^-1 cm^-2, a linear range of 5.00 μmol/L-11.00 mmol/L, and a detection limitation of 1 μmol/L in H₂O₂ detection, and a good glucose detection performance with 5 μmol/L. These excellent electrochemical performances endow the hollow Co₃O₄/NCNTs as promising alternative to enzymes in the biological applications.