NiCo-LDH nanoflake arrays-supported Au nanoparticles on copper foam as a highly sensitive electrochemical non-enzymatic glucose sensor

Highlights: • In-situ galvanic replacement and electrodeposition growth of LDH@Au/Cu on three-dimensional (3D) copper foam. • 3D LDH@Au/Cu honeycomb like architecture works as a binder-free electrode for non-enzymatic glucose sensing. • 3D LDH@Au/Cu electrode exhibits an ultra-prompt response time of 0.5 s and a high sensitivity of 23100 μA mM⁻¹ cm⁻². • Remarkable anti-interference capability and favorable stability of LDH@Au/Cu electrode. The detection of glucose in human blood is of great importance in the diagnosis and prevention of diabetes. In this work, we fabricated a novel electrochemical non-enzymatic glucose sensor, NiCo-LDH nanoflake arrays-supported Au nanoparticles on copper foam (NiCo-LDH@ Au/Cu) by galvanic replacement and electrodeposition methods. Owing to the synergistic effect of three-dimensional (3D) architecture of Cu foam, high electrocatalytic activity of Au nanoparticles and NiCo-LDH nanoflake arrays, the LDH@Au/Cu electrode exhibits excellent electrocatalytic ability for glucose oxidation in NaOH solution. Under optimized conditions, the LDH@Au/Cu electrode shows excellent activity with a linear range from 0.5 to 3000 μM at the potential of 0.50 V (vs. Ag/AgCl), a low detection limit of 0.23 μM (S/N = 3), an ultra-prompt response time of 0.5 s, and a high sensitivity of 23100 μA mM⁻¹ cm⁻², as well as good selectivity and stability. Furthermore, the as-fabricated non-enzymatic glucose sensor was successfully applied to the glucose detection in human serum as a promising candidate in the development of electrochemical non-enzymatic glucose sensor.