Two-dimensional hybrid mesoporous Fe2O3–graphene nanostructures: A highly active and reusable peroxidase mimetic toward rapid, highly sensitive optical detection of glucose

• Two-dimensional mFe2O3–G was developed as a peroxidase mimetic for the first time.
• mFe2O3–G exhibits high catalytic activities toward TMB oxidation by H2O2.
• mFe2O3–G was used for rapid, highly sensitive and selective optical glucose detection.

In this article, for the first time, two-dimensional hybrid mesoporous Fe2O3–graphene (mFe2O3–G) nanostructures were developed as a peroxidase mimetic with catalytic activities superior to those of mFe2O3, G, and previously reported Fe-based peroxidase mimetics. The high-surface-area mFe2O3 not only offers a large number of catalytically active sites, but also facilitates the diffusion of 3,3,5,5-tetramethylbenzidine (TMB) and H2O2 toward G surface. On the other hand, G is π-rich and thus favors the adsorption and enrichment of TMB within these pores. These synergistic effects lead to highly improved catalytic performances. Based on these findings, a simple, rapid, and highly sensitive and selective optical detector of glucose has been developed and demonstrated in buffer solution with a pretty low detection limit of 0.5 μM. In addition, this nanosensor is reusable and can also be used for glucose detection in diluted serum.