Facile synthesis of trimetallic compounds based on nickel and cobalt with aluminum-halloysite nanotubes complex for electrochemical applications of imidacloprid

This research used the hydrothermal synthesis to prepare a ternary NiCoAl layered double hydroxide (NiCoAl-LDH) integrated onto the surface of the calcined halloysite nanotubes (c-HNTs). The resulting NiCoAl-LDHs@c-HNTs nanocomposite was thoroughly characterized using XRD to confirm its phase purity and crystallinity, XPS to analyze the chemical state of the elements, and SEM/TEM/EDX to examine its structural morphology and elemental composition. Furthermore, these analyses revealed the successful and uniform formation of LDH nanosheets onto c-HNTs surfaces. The NiCoAl-LDHs@c-HNTs electrode displayed outstanding electrochemical activity toward the detection of the neonicotinoid pesticide imidacloprid (IMI), demonstrating a broad linear range from 0.1 to 1087 µM, a low limit of detection (0.026 µM), and high sensitivity of 7.4 µA µM− 1 cm− 2. The sensor exhibited strong reliability with relative standard deviations (RSDs) below 5% for repeatability and reproducibility, along with high operational stability and selectivity in the presence of related interferents. Furthermore, the real-time application was confirmed by testing environmental water samples, which is sediment water, riverside water, fish tank water, and tap water, where recovery rates ranged from ~95 to 100%, highlighting its potential for monitoring neonicotinoid contamination and its impact on human health and ecosystems through the food chain.