Cobalt oxide nanosheets wrapped onto nickel foam for non-enzymatic detection of glucose

Ultra-sensitive and highly selective detection of glucose is essential for the clinical diagnosis of diabetes. In this paper, an ultra-sensitive glucose sensor was successfully fabricated based on cobalt oxide (Co₃O₄) nanosheets directly grown on nickel foam through a simple hydrothermal method. Characterizations indicated that the Co₃O₄ nanosheets are completely and uniformly wrapped onto the surface of nickel foam to form a three-dimensional heterostructure. The resulting self-standing electrochemical electrode presents a high performance for the non-enzymatic detection of glucose, including short response time (<10 s), ultra-sensitivity (12.97 mA mM^-1 cm^-2), excellent selectivity and low detection limit (0.058 μM, S/N = 3). These results indicate that Co₃O₄ nanosheets wrapped onto nickel foam are a low-cost, practical, and high performance electrochemical electrode for bio sensing.