Surface engineering induced urchin-like CuFe oxides on copper foam for highly sensitive non-enzymatic glucose sensing.

Surface morphology and catalytic sites are crucial for constructing self-supported electrode applying in non-enzymatic electrochemical glucose sensing. In this study, we adopted a surface engineering strategy to coat Prussian blue analogue (PBA) on Cu foam as precursor, and the thickness of PBA film controls the morphology and component content of the annealing products, CuFe oxides supported on Cu foam (CuFeO x /CF). With optimal PBA film thickness, CuFeO x /CF can be endowed with urchin-like morphology and multiple catalytic sites. The urchin-like CuFeO x /CF possessed more electrochemical active surface area, stronger electrocatalytic ability, and less charge transfer resistance than CuO x /CF obtained from direct annealing CF. Thus, the CuFeO x /CF was proved to be an effective platform for electrochemical glucose sensing, owing to the hierarchical structure, component synergistic effect and excellent electrical conductivity. Specifically, high sensitivity of 9536 and 2614 μA mM−1 cm−2 at corresponding linear concentration range of 4.9–396 and 396–1224 μM, and low limit of detection of 0.55 μΜ (S/N=3) were achieved by CuFeO x /CF electrode in glucose sensing. Moreover, fast response, excellent reproducibility, superior long-term stability, robust anti-interference ability, and satisfactory practical recovery in non-enzymatic glucose analysis were effectuated by designed CuFeO x /CF sensor. This study demonstrated the surface engineering induced CuFeO x /CF can be an ideal self-supported electrode for non-enzymatic glucose sensor with high sensitivity and stability. [Display omitted] • Cu foam supported urchin-like FeCu oxides (FeCuO x /CF) was fabricated. • Surface PBA contributed to the hierarchy and multiple catalytic sites of FeCuO x /CF. • Hybrid FeCu oxides enhanced the electrocatalytic activity for glucose oxidation. • High sensitivity of 9536 μA mM−1 cm−2 and low LOD of 0.55 μM (S/N=3) was achieved. [ABSTRACT FROM AUTHOR]