Engineering of nickel phosphate nanodots modified copper phosphate microflowers for highly efficient glucose monitoring

Abstract

Transition metal phosphates have garnered significant interest as effective electrocatalysts due to their admirable chemical stability, unique physical features, low cost and exceptional electrocatalytic properties. Here, we design for the first time, a binary metal phosphate (BMP) heteroarchitecture based on nickel phosphate nanodots supported on copper phosphate microflowers (NDTs Ni3(PO4)2@Cu3(PO4)2 MFs). The surface characterizations reveal the interconnected cross-network of vertically oriented 3D nanosheets (NSs) which leads to the self-assembly of microflowers. In addition, the Ni3(PO4)2 nanodots, with an average diameter of 2.6 nm, are uniformly distributed throughout the structure, providing greater number of active centers on the surface of the designed catalyst. Thus, the customized structure has the potential to function as an excellent electrocatalyst by providing sufficient reaction space through the highly exposed edges of 3D nanosheets, and high density active site owe to the presence of NDTs. Typically, the Cu3(PO4)2 acts as an electron mediator by facilitating the Cu2+/Cu3+ redox couple, while the Ni3(PO4)2 enhances the electrocatalytic oxidation of glucose. Thus, owing to its unique physical and chemical aspects, the NDTs Ni3(PO4)2@Cu2(PO4)2 MFs demonstrate superior electrocatalytic efficacy for glucose sensing. Thanks to the novel NDTs Ni3(PO4)2@Cu2(PO4)2 MFs BMP for offering exceptional sensitivities (2197.119 and 206.111 μA mM–1 cm–2), a wide detection range (0.009–0.491 mM and 0.491–14.83 mM), a short response time (<1 s), and a low detection limit (0.06 μM, S/N = 3). Moreover, the designed sensor presents good reproducibility, admirable stability and excellent selectivity. Thus, the NDTs Ni3(PO4)2@Cu3(PO4)2 MFs are promising for the potential applications in glucose sensor, to monitor glucose in human serum and other body fluids.