Surfactant-assisted imidacloprid intercalation of layered zinc hydroxide nitrate: synthesis, characterisation and controlled release formulation

摘要

A neutrally charged insecticide, imidacloprid (IC), has been intercalated into zinc hydroxide nitrate (ZHN) with the assistance of sodium dodecylsulphate (SDS). The presence of SDS assists the intercalation of IC by forming a hydrophobic region in the interlayer gallery of ZHN. The intercalated compound, ZHN-SDS-IC, was characterised using powder X-ray diffraction (PXRD), thermogravimetric analysis, Fourier transform infrared spectroscopy, elemental analysis, field emission scanning electron microscopy, and gas sorption analysis. The PXRD studies demonstrated intercalation peaks at lower 2 theta, which confirmed the intercalation of IC and SDS in the interlayer gallery of ZHN. The release and kinetic studies of ZHN-SDS-IC reveals that the IC were successfully released in controlled manner (with release time up to 1478 min), and were governed by pseudo second order kinetic model. The ZHN-SDS-IC synthesised is hopefully beneficial in overcoming the consequences of excessive usage of insecticide in paddy cultivation.