Fe.sub.2V.sub.4O.sub.13 photoanode material: an interesting approach to non-enzymatic glucose oxidation

The use of non-enzymatic material for the electrooxidation reaction of glucose is still a challenge to be overcome since these materials must have high sensitivity to glucose, high chemical stability and, if possible, be obtained quickly and with a low-cost process. In this context, iron vanadate (Fe.sub.2V.sub.4O.sub.13) was successfully synthesized using the easy and low-cost Successive Ionic Layer Adsorption and Reaction process and used as an interesting non-enzymatic photoanode material approach for the photoelectrochemical oxidation reaction of glucose. From the X-ray diffraction and Raman measurements, it was possible to observe that the monoclinic crystalline phase Fe.sub.2V.sub.4O.sub.13 was formed at 500 °C, without any secondary phases. The electrochemical characterization, performed by linear sweep voltammetry (LSV), chronoamperometry and electrochemical impedance spectroscopy techniques, under light condition, showed the remarkable photoelectrochemical activity of the FTO/Fe.sub.2V.sub.4O.sub.13 electrode, such as a high photocurrent density at + 0.6 V vs. Ag/AgCl (0.2 mA cm.sup.-2); good reproducibility under transient light condition; low charge transfer resistance; and flat band potential consistent with the LSV and typical value of this material (+ 0.45 V). The performance of the electrode as non-enzymatic glucose interaction, carried out by chronoamperometry technique, showed a remarkable performance in the photoelectrooxidation reaction of glucose, with linear behavior (R.sup.2 = 0.9975) of the analytical curve (glucose concentration from 0 to 10 mmol L.sup.-1), excellent reproducibility, a slight loss in photoelectrochemical signal after five successive reading cycles, good sensitivity (0.370 [mu]A mM.sup.-1 cm.sup.-2) and limit of detection (52 [micro]mol L.sup.-1). Besides, the analysis of interference species showed good electrode selectivity. Graphical abstract Fe.sub.2V.sub.2O.sub.13 photoelectrode obtained by the Successive Ionic Layer Adsorption and Reaction (SILAR) process, and its use for glucose photoelectrocatalytic oxidation reaction