Engineering hybrid CuS/Co₃S₄ nanocages by ion reutilization for highly sensitive glucose sensing platforms

Constructing hybrid hollow nano-electrocatalysts with various transition metal sulfides (TMSs) is highly desirable for sensitive enzyme-free glucose monitoring, but limited research has been conducted due to the constraints of current demanding synthesis technologies. In this study, we integrated CuS and Co₃S₄ as hybrid nanocages (h-NCs) by advanced synthetic strategies, including coordinated etching and precipitation (CEP) and template ion reutilization. The resulting CuS/Co₃S₄ h-NCs induced good synergistic effect in electrocatalytic activities, glucose adsorption, and electrical conductivity, as validated by the density functional theory (DFT) calculations. When employed as glucose sensing platforms, electrodes incorporating CuS/Co₃S₄ h-NCs demonstrated high-performance sensing characteristics, with excellent sensitivities up to 2731.8 μA mM^-1 cm², wide linear range of 0.001-5.6 mM, low detection limit (90 nM), and ideal stability. Moreover, CuS/Co₃S₄ h-NCs were promising to analyze glucose in human serum with good recoveries ranging from 92.4 % to 96.7 %. These findings underscore the benefits of integrating different TMSs to create hybrid hollow nanomaterials, which optimize glucose sensing platforms and expand the design of high-performance electrocatalysts.