Fe۲O۳/CuO Hybrid Nanostructures as Electrode Materials for Glucose Detection

In order to solve the disadvantages of using Fe۲O۳ nanoparticles in electrocatalytic processes, in this work, a series of Fe۲O۳/CuO hybrid nanostructures with different molar ratios of Fe۳+ to Cu۲+ ions were produced and their structure was investigated using various methods. Then, the compounds were used as electrode materials for electrochemical detection of glucose in alkaline solution. The results showed that the electrode containing pristine Fe۲O۳ shows no significant activity for glucose oxidation. Since FeIII oxide contains active electrocatalytic positions, this performance can be due to poor electrical conductivity. Investigations showed that when Fe۲O۳ and CuO nanoparticles are combined, the activity against glucose is improved by reducing the band gap and increasing the electrical conductivity. It was found that the ability of nanocomposites to recognize glucose depends on the molar ratios of Fe۳+ and Cu۲+ ions present in the structure, and the highest electrocatalytic performance is observed when the molar ratio of metal ions is equal. Fe۲O۳/CuO (۰.۵:۰.۵) nanocomposite shows the best activity for glucose oxidation in terms of high sensitivity, low detection limit and wide linear range due to its low Tafel slope, low charge transfer resistance, high electrochemically active surface area, low band gap and high electrical conductivity. In addition, this compound shows high stability, selectivity, and applicability for blood glucose detection with a reasonable recovery rate. In conclusion, the synergistic effects between Fe۲O۳ and CuO increase the number of active catalytic sites and rapid charge transfer on the electrode surface and promote the electrocatalytic activity towards glucose.