NiCu-layered double hydroxide-modified CuO nanorods for enhanced non-enzymatic glucose sensing

A flexible non-enzymatic glucose sensor with high sensitivity (NiCu-LDH/CuO/NCC) was prepared by growing NiCu-layered double hydroxide (NiCu-LDH)-modified CuO nanorods on N-doped carbon cloth (NCC) using hydrothermal method and electrodeposition. The NCC provided abundant attachment sites and good electrical conductivity for CuO nanorods, and the hierarchical nanostructures (NiCu-LDH/CuO) had large specific surface area and highly catalytic active sites, which facilitated the electrooxidation of glucose. The effect of the ratio of Ni to Cu on the electrocatalytic performance of NiCu-LDH/CuO/NCC was evaluated. The results indicated that the optimized NiCu-LDH/CuO/NCC (Ni/Cu molar ratio of 2:1) had good electrocatalytic oxidation toward glucose, and exhibited high sensitivity (11.545 mA cm^-2 mM^-1), low detection limit (0.26 μM), large linear range (0.001-1.5 mM), and good stability (95% after 28 days). Therefore, the hierarchical nanostructure is suitable for the construction of flexible non-enzymatic glucose sensors with high sensitivity, indicating that the combination of transition metal oxides and LDH provides a unique opportunity for designing high-performance electrochemical non-enzymatic glucose sensors.