Near-infrared light-promoted engineering oxygen vacancy of Fe3Ov-Mo/P nanozyme for sensitive detection of glyphosate

Abstract

The rapid and sensitive detection of glyphosate herbicide in agricultural products is urgent need. Herein, we develop a photosensitive Fe3Ov-Mo/P nanozyme with defect-rich rough surface by the co-precipitation method. In particular, the Fe3Ov-Mo/P nanozyme with high-percentage oxygen vacancy (OV) defects and rough surface exhibited superior peroxidase (POD)-like activity and kinetics. More intriguingly, Fe3Ov-Mo/P nanozyme with strong optical absorption in near-infrared (NIR) region showed excellent light-promoted POD-like activity. It was found that the defect-rich rough surface is conducive to the adsorption of glyphosate to inhibit the POD-like activity of Fe3Ov-Mo/P. Under near-infrared laser irradiation, the inhibitory effect of glyphosate on the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) by Fe3Ov-Mo/P was increased by 2.64 times. A colorimetric platform was developed for the detection of glyphosate with a low detection limit of 0.032 mg kg -1 and good selectivity. The method was used to determine the residual glyphosate in coffee, and the recovery efficiency was between 91.20–104.00 %. This work that combines the advantage of defect engineering and NIR provides a strategy for developing high-active nanozyme in pesticide assay.