Mesoporous NiO nanosphere: a sensitive strain sensor for determination of hydrogen peroxide

Abstract

Exploring the sensitive and reliable methods for the determination of hydrogen peroxide (H₂O₂) is a crucial issue for the health and environmental challenges. Herein, we demonstrate a facile, but rational and effective solvothermal approach to the synthesis of hierarchical NiO mesoporous nanospheres (NiO-MNS) as an effective non-enzymatic sensor towards the H₂O₂ detection. Owing to the intercalation and stabilization effect of polyethylene glycol for the Ni(OH)₂ intermediate, the NiO mesoporous nanosphere (NiO-MNS) product is consistent with the low-dimensional nanostructured NiO blocks with large surface area and plentiful mesopores after the calcination treatment. The obtained NiO-MNS sensor presents superior electrochemical performance with a high sensitivity (236.7 μA mM^-1 cm^-2) and low limit of detection (0.62 μM), as well as the good selectivity and reliability for the further application of H₂O₂ detection. In addition, the unraveling mechanism of the mesopores formation derived from the <i>in situ</i> measurements also offers the valuable guidance for the future design of porous materials for electrochemical devices and other applications.