Hybridization of Co3O4 and α-MnO2 Nanostructures for High-Performance Nonenzymatic Glucose Sensing

This work reports a highly sensitive and selective nonenzymatic detection of glucose that has been achieved by hybridization of 1D α-MnO 2 nanorods modified with surface decoration of Co 3 O 4 nanoparticles. The rational design and controlled synthesis of the hybrid nanostructures are of great importance in enabling the fine tuning of their properties and functions. First-principles-based periodic hybrid unrestricted HSE06 DFT with Grimme’s long-range dispersion corrections are employed to compute the equilibrium crystal structures and electronic properties (i.e., band structure, Fermi energy level, and density of states) of both materials. These calculations reveal that both the α-MnO 2 and the Co 3 O 4 materials are indirect band gap semiconductor, and the band gap is about 2.89 and 3.18 eV, respectively. The α-MnO 2 /Co 3 O 4 hybrid nanostructure has been synthesized by a simple and economical hydrothermal method. Compared with the performances of pure components MnO 2 nanorods and Co 3 O 4 nanoparticles, these hybrid nanostructures demonstrated a maximum electrooxidation toward glucose. The glucose-sensing performances of fabricated hybrid structures were measured by cyclic voltammetry (CV) and chronoamperometry. The synthesized α-MnO 2 /Co 3 O 4 electrode exhibited a high sensitivity of 127 μA mM –1 cm –2 (S/N = 3) with a detection limit of 0.03 μM, wide linear range from 60 μM to 7 mM of glucose, with a short response time of less than 5 s. The favorable properties of the nanostructure fortify its potential utilization in the clinical detection of diabetes.