Bioengineering of one dimensional hierarchical Cu₇S₄ hollow nanotubes for non-enzymatic glucose sensing applications

Herein, a novel and facile eco-friendly green chemistry approach has been devised at room temperature for synthesis of 1D hierarchical Cu₇S₄ hollow nanotubes on Cu substrate via volatile organosulfur compounds from Allium sativum L for non-enzymatic glucose detection. Field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), and X-ray spectroscopy (XPS) were employed to characterize the surface morphology, structural phase, compositional, and chemical states of the obtained samples, respectively. The SEM results confirm the formation of 1D hierarchical Cu₇S₄ hollow nanotubes. The XRD patterns are indexed to orthogonal anilite Cu₇S₄ crystal planes and the EDX spectra clearly reveal the presence of Cu and S elements. XPS spectra confirms peaks of Cu 2p and S 1s core levels, which are typical characteristics of Cu(i) and S(ii), respectively. The Brunauer-Emmett-Teller (BET) specific surface area for obtained Cu₇S₄ hollow nanotubes is 2.07 m² g^-1 with a pore size distribution of 27.90 nm. Using Cu₇S₄ hollow nanotubes, the detection of non-enzymatic glucose was conducted over a dynamic range of concentrations from 0.5 to 100 μmol L^-1 and reveals a high sensitivity of 1058.33 μA mM^-1cm^-2 and a limit of detection (LOD) of 0.127 μmol L^-1. The obtained results indicated that Cu₇S₄ hollow nanotubes are promising candidates for non-enzymatic glucose detection.