Ultrasensitive electrochemical sensor for fenitrothion based on MIL-125 derived iron/titanium bimetallic oxides doped porous carbon composite

Fenitrothion (FT) is a common organophosphorus pesticide widely used in agricultural. Residues of fenitrothion in crops can adversely affect human health. In this work, modified MIL-125-Fe was prepared by changing the solvent ratios and further etching with iron nitrate, followed by high-temperature pyrolysis to obtain modified-TiO2/FeTiO3-doped nitrogen-containing carbon framework (m-TiO2/FeTiO3@NCF). The porous carbon material of m-TiO2/FeTiO3@NCF was used to modify the GCE to produce FT electrochemical sensor. Under optimized conditions, the sensor exhibited good detection performance for FT with a low LOD of 0.96 nM and a wide detection linear range of 1–9000 nM, and also exhibited good reproducibility (RSD = 2.08 %), repeatability (RSD = 1.09 %) and anti-interference performance. The sensor was successfully applied in real sample tests showing the recovery rates of 98.7 %–101.2 %. The present study provides a new idea for the rapid and accurate detection of FT.