Synthesis of Ni-Co Hydroxide Nanosheets Constructed Hollow Cubes for Electrochemical Glucose Determination

Hierarchical Ni-Co double transition metal hydroxide nanosheets have been explored as an effective strategy for the design of nonenzymatic glucose sensors. Ni-Co hydroxide nanosheets constructed hollow cubes were successfully synthesized by using Cu(2)O cubes as templates and subsequently etched by Na(2)S(2)O(3) to achieve a hollow cubic structure. The molar ratio between Ni and Co was tuned by varying the precursor ratio of NiCl(2) and CoCl(2). It was observed by transmission electron microscopy (TEM) that the increasing Ni precursor resulted in particle morphology, and the increasing ratio of the Co precursor resulted in more lamellar morphology. The sample with the composition of Ni(0.7)Co(0.3)(OH)(2) displayed the best performance for glucose sensing with high selectivity (1541 μA mM(–1) cm(–2)), low detection limit (3.42 µM with S/N = 3), and reasonable selectivity. Similar strategies could be applied for the design of other electrode materials with high efficiency for nonenzymatic glucose determination.