Two-dimensional copper oxide/zinc oxide nanoflakes with three-dimensional flower-like heterostructure enhanced with electrocatalytic activity toward nimesulide detection

Abstract

The strategy of building two-dimensional (2D) metal oxide nanoflakes has inspired several innovations in different fields of application on account of its tremendous significance. It includes ultrathin planar surface, large charge carrier mobility, and tunable band structures, providing unprecedented features for sensing. Moreover, the intercalation of 2D dimensions to 3D superstructures will result in improved and dual advantages of both 2D/3D. The construction of 2D/3D copper oxide zinc oxide nanocomposite as electrode material for specific detection of nimesulide (NMS) is herein reported. The conversion of 2D CZ nanoflakes to 3D CZ microflowers was possibly achieved via the self-assembly process. This simple and cost-effective development of the CZ composite was characterized for evaluating the physical, chemical, and morphological properties. The highly crystalline nature of CZ was observed from powder X-ray diffraction and X-ray photoelectron spectroscopy analysis. The formation of 2D nanoflakes of CZ was strongly confirmed from field emission scanning electron microscopy and high-resolution transmission electron microscopy images. To verify the strong attachments, Fourier transforms infrared spectroscopy spectra were analyzed. Electrochemical sensing of NMS at CZ fabricated glassy carbon electrode reflects higher electrocatalytic activity with a linear range of NMS addition from 0.299 μM to 319.15 μM. The lower detection limit was about 0.005 μM with a sensitivity of 7.152 μAμM−1 cm2. The CZ nanocomposite will be more applicable for sensing several drugs with enriched active sites, higher conductivity, and large surface area raised from low-cost metal oxides when compared with highly conducting materials.