Synthesis and characterization of Co3O4 ultra-nanosheets and Co3O4 ultra-nanosheet-Ni(OH)2 as non-enzymatic electrochemical sensors for glucose detection

The present study examines the synthesis of Co3O4 ultra-nanosheets (Co3O4 UNSs) and Co3O4 ultra-nanosheet-Ni(OH)2 (Co3O4 UNS-Ni(OH)2) via solvothermal process and their application as non-enzymatic electrochemical sensors for glucose detection. X-ray diffraction and transmission electron microscopy results confirmed the Co3O4 UNS deposition on Ni(OH)2 surface. The presence of Co3O4 UNSs on Ni (OH) 2 surface improved the sensitivity of glucose detection, from the increase of glucose oxidation peak current at the Co3O4 UNS-Ni(OH)2/glassy carbon electrode (current density: 2000 μA·cm− 2), compared to the Co3O4 UNSs. These results confirmed that Ni(OH)2 on glassy carbon electrode is a sensitive material for glucose detection, moreover the Co3O4 UNSs can increase the interaction and detection of glucose due to their high surface area. The estimated limit of detection (S/N = 3) and limit of quantification (S/N = 10) of the linear segment (5-40 μM) are 1.08 μM and 3.60 μM respectively. The reproducibility experiments confirmed the feasibility of Co3O4 UNS-Ni(OH)2 for the quantitative detection of certain concentration ranges of glucose.